Add support for engine calls from plugins (#12029)

# Description

This allows plugins to make calls back to the engine to get config,
evaluate closures, and do other things that must be done within the
engine process.

Engine calls can both produce and consume streams as necessary. Closures
passed to plugins can both accept stream input and produce stream output
sent back to the plugin.

Engine calls referring to a plugin call's context can be processed as
long either the response hasn't been received, or the response created
streams that haven't ended yet.

This is a breaking API change for plugins. There are some pretty major
changes to the interface that plugins must implement, including:

1. Plugins now run with `&self` and must be `Sync`. Executing multiple
plugin calls in parallel is supported, and there's a chance that a
closure passed to a plugin could invoke the same plugin. Supporting
state across plugin invocations is left up to the plugin author to do in
whichever way they feel best, but the plugin object itself is still
shared. Even though the engine doesn't run multiple plugin calls through
the same process yet, I still considered it important to break the API
in this way at this stage. We might want to consider an optional
threadpool feature for performance.

2. Plugins take a reference to `EngineInterface`, which can be cloned.
This interface allows plugins to make calls back to the engine,
including for getting config and running closures.

3. Plugins no longer take the `config` parameter. This can be accessed
from the interface via the `.get_plugin_config()` engine call.


# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
Not only does this have plugin protocol changes, it will require plugins
to make some code changes before they will work again. But on the plus
side, the engine call feature is extensible, and we can add more things
to it as needed.

Plugin maintainers will have to change the trait signature at the very
least. If they were using `config`, they will have to call
`engine.get_plugin_config()` instead.

If they were using the mutable reference to the plugin, they will have
to come up with some strategy to work around it (for example, for `Inc`
I just cloned it). This shouldn't be such a big deal at the moment as
it's not like plugins have ever run as daemons with persistent state in
the past, and they don't in this PR either. But I thought it was
important to make the change before we support plugins as daemons, as an
exclusive mutable reference is not compatible with parallel plugin
calls.

I suggest this gets merged sometime *after* the current pending release,
so that we have some time to adjust to the previous plugin protocol
changes that don't require code changes before making ones that do.

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`


# After Submitting
I will document the additional protocol features (`EngineCall`,
`EngineCallResponse`), and constraints on plugin call processing if
engine calls are used - basically, to be aware that an engine call could
result in a nested plugin call, so the plugin should be able to handle
that.
This commit is contained in:
Devyn Cairns 2024-03-09 09:26:30 -08:00 committed by GitHub
parent c6d4e4f890
commit 430fb1fcb6
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
33 changed files with 2053 additions and 232 deletions

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@ -16,7 +16,7 @@
//! invoked by Nushell.
//!
//! ```rust,no_run
//! use nu_plugin::{EvaluatedCall, LabeledError, MsgPackSerializer, Plugin, serve_plugin};
//! use nu_plugin::*;
//! use nu_protocol::{PluginSignature, Value};
//!
//! struct MyPlugin;
@ -26,9 +26,9 @@
//! todo!();
//! }
//! fn run(
//! &mut self,
//! &self,
//! name: &str,
//! config: &Option<Value>,
//! engine: &EngineInterface,
//! call: &EvaluatedCall,
//! input: &Value
//! ) -> Result<Value, LabeledError> {
@ -37,7 +37,7 @@
//! }
//!
//! fn main() {
//! serve_plugin(&mut MyPlugin{}, MsgPackSerializer)
//! serve_plugin(&MyPlugin{}, MsgPackSerializer)
//! }
//! ```
//!
@ -49,7 +49,7 @@ mod protocol;
mod sequence;
mod serializers;
pub use plugin::{serve_plugin, Plugin, PluginEncoder, StreamingPlugin};
pub use plugin::{serve_plugin, EngineInterface, Plugin, PluginEncoder, StreamingPlugin};
pub use protocol::{EvaluatedCall, LabeledError};
pub use serializers::{json::JsonSerializer, msgpack::MsgPackSerializer};

View File

@ -1,36 +1,166 @@
use std::sync::{atomic::AtomicBool, Arc};
use nu_engine::get_eval_block_with_early_return;
use nu_protocol::{
ast::Call,
engine::{EngineState, Stack},
engine::{Closure, EngineState, Stack},
Config, PipelineData, ShellError, Span, Spanned, Value,
};
use super::PluginIdentity;
/// Object safe trait for abstracting operations required of the plugin context.
pub(crate) trait PluginExecutionContext: Send + Sync {
/// The [Span] for the command execution (`call.head`)
fn command_span(&self) -> Span;
/// The name of the command being executed
fn command_name(&self) -> &str;
/// The interrupt signal, if present
fn ctrlc(&self) -> Option<&Arc<AtomicBool>>;
/// Get engine configuration
fn get_config(&self) -> Result<Config, ShellError>;
/// Get plugin configuration
fn get_plugin_config(&self) -> Result<Option<Value>, ShellError>;
/// Evaluate a closure passed to the plugin
fn eval_closure(
&self,
closure: Spanned<Closure>,
positional: Vec<Value>,
input: PipelineData,
redirect_stdout: bool,
redirect_stderr: bool,
) -> Result<PipelineData, ShellError>;
}
/// The execution context of a plugin command. May be extended with more fields in the future.
/// The execution context of a plugin command.
pub(crate) struct PluginExecutionCommandContext {
ctrlc: Option<Arc<AtomicBool>>,
identity: Arc<PluginIdentity>,
engine_state: EngineState,
stack: Stack,
call: Call,
}
impl PluginExecutionCommandContext {
pub fn new(
identity: Arc<PluginIdentity>,
engine_state: &EngineState,
_stack: &Stack,
_call: &Call,
stack: &Stack,
call: &Call,
) -> PluginExecutionCommandContext {
PluginExecutionCommandContext {
ctrlc: engine_state.ctrlc.clone(),
identity,
engine_state: engine_state.clone(),
stack: stack.clone(),
call: call.clone(),
}
}
}
impl PluginExecutionContext for PluginExecutionCommandContext {
fn command_span(&self) -> Span {
self.call.head
}
fn command_name(&self) -> &str {
self.engine_state.get_decl(self.call.decl_id).name()
}
fn ctrlc(&self) -> Option<&Arc<AtomicBool>> {
self.ctrlc.as_ref()
self.engine_state.ctrlc.as_ref()
}
fn get_config(&self) -> Result<Config, ShellError> {
Ok(nu_engine::get_config(&self.engine_state, &self.stack))
}
fn get_plugin_config(&self) -> Result<Option<Value>, ShellError> {
// Fetch the configuration for a plugin
//
// The `plugin` must match the registered name of a plugin. For
// `register nu_plugin_example` the plugin config lookup uses `"example"`
Ok(self
.get_config()?
.plugins
.get(&self.identity.plugin_name)
.cloned()
.map(|value| {
let span = value.span();
match value {
Value::Closure { val, .. } => {
let input = PipelineData::Empty;
let block = self.engine_state.get_block(val.block_id).clone();
let mut stack = self.stack.captures_to_stack(val.captures);
let eval_block_with_early_return =
get_eval_block_with_early_return(&self.engine_state);
match eval_block_with_early_return(
&self.engine_state,
&mut stack,
&block,
input,
false,
false,
) {
Ok(v) => v.into_value(span),
Err(e) => Value::error(e, self.call.head),
}
}
_ => value.clone(),
}
}))
}
fn eval_closure(
&self,
closure: Spanned<Closure>,
positional: Vec<Value>,
input: PipelineData,
redirect_stdout: bool,
redirect_stderr: bool,
) -> Result<PipelineData, ShellError> {
let block = self
.engine_state
.try_get_block(closure.item.block_id)
.ok_or_else(|| ShellError::GenericError {
error: "Plugin misbehaving".into(),
msg: format!(
"Tried to evaluate unknown block id: {}",
closure.item.block_id
),
span: Some(closure.span),
help: None,
inner: vec![],
})?;
let mut stack = self.stack.captures_to_stack(closure.item.captures);
// Set up the positional arguments
for (idx, value) in positional.into_iter().enumerate() {
if let Some(arg) = block.signature.get_positional(idx) {
if let Some(var_id) = arg.var_id {
stack.add_var(var_id, value);
} else {
return Err(ShellError::NushellFailedSpanned {
msg: "Error while evaluating closure from plugin".into(),
label: "closure argument missing var_id".into(),
span: closure.span,
});
}
}
}
let eval_block_with_early_return = get_eval_block_with_early_return(&self.engine_state);
eval_block_with_early_return(
&self.engine_state,
&mut stack,
block,
input,
redirect_stdout,
redirect_stderr,
)
}
}
@ -40,7 +170,38 @@ pub(crate) struct PluginExecutionBogusContext;
#[cfg(test)]
impl PluginExecutionContext for PluginExecutionBogusContext {
fn command_span(&self) -> Span {
Span::test_data()
}
fn command_name(&self) -> &str {
"bogus"
}
fn ctrlc(&self) -> Option<&Arc<AtomicBool>> {
None
}
fn get_config(&self) -> Result<Config, ShellError> {
Err(ShellError::NushellFailed {
msg: "get_config not implemented on bogus".into(),
})
}
fn get_plugin_config(&self) -> Result<Option<Value>, ShellError> {
Ok(None)
}
fn eval_closure(
&self,
_closure: Spanned<Closure>,
_positional: Vec<Value>,
_input: PipelineData,
_redirect_stdout: bool,
_redirect_stderr: bool,
) -> Result<PipelineData, ShellError> {
Err(ShellError::NushellFailed {
msg: "eval_closure not implemented on bogus".into(),
})
}
}

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@ -3,11 +3,11 @@ use crate::protocol::{CallInfo, EvaluatedCall};
use std::path::{Path, PathBuf};
use std::sync::Arc;
use nu_engine::{get_eval_block, get_eval_expression};
use nu_engine::get_eval_expression;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{ast::Call, PluginSignature, Signature};
use nu_protocol::{Example, PipelineData, ShellError, Value};
use nu_protocol::{Example, PipelineData, ShellError};
#[doc(hidden)] // Note: not for plugin authors / only used in nu-parser
#[derive(Clone)]
@ -72,7 +72,6 @@ impl Command for PluginDeclaration {
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let eval_block = get_eval_block(engine_state);
let eval_expression = get_eval_expression(engine_state);
// Create the EvaluatedCall to send to the plugin first - it's best for this to fail early,
@ -80,32 +79,6 @@ impl Command for PluginDeclaration {
let evaluated_call =
EvaluatedCall::try_from_call(call, engine_state, stack, eval_expression)?;
// Fetch the configuration for a plugin
//
// The `plugin` must match the registered name of a plugin. For
// `register nu_plugin_example` the plugin config lookup uses `"example"`
let config = nu_engine::get_config(engine_state, stack)
.plugins
.get(&self.identity.plugin_name)
.cloned()
.map(|value| {
let span = value.span();
match value {
Value::Closure { val, .. } => {
let input = PipelineData::Empty;
let block = engine_state.get_block(val.block_id).clone();
let mut stack = stack.captures_to_stack(val.captures);
match eval_block(engine_state, &mut stack, &block, input, false, false) {
Ok(v) => v.into_value(span),
Err(e) => Value::error(e, call.head),
}
}
_ => value.clone(),
}
});
// We need the current environment variables for `python` based plugins
// Or we'll likely have a problem when a plugin is implemented in a virtual Python environment.
let current_envs = nu_engine::env::env_to_strings(engine_state, stack).unwrap_or_default();
@ -122,8 +95,9 @@ impl Command for PluginDeclaration {
}
})?;
// Create the context to execute in
// Create the context to execute in - this supports engine calls and custom values
let context = Arc::new(PluginExecutionCommandContext::new(
self.identity.clone(),
engine_state,
stack,
call,
@ -134,7 +108,6 @@ impl Command for PluginDeclaration {
name: self.name.clone(),
call: evaluated_call,
input,
config,
},
context,
)

View File

@ -22,6 +22,7 @@ use crate::{
mod stream;
mod engine;
pub use engine::EngineInterface;
pub(crate) use engine::{EngineInterfaceManager, ReceivedPluginCall};
mod plugin;

View File

@ -1,16 +1,19 @@
//! Interface used by the plugin to communicate with the engine.
use std::sync::{mpsc, Arc};
use std::{
collections::{btree_map, BTreeMap},
sync::{mpsc, Arc},
};
use nu_protocol::{
IntoInterruptiblePipelineData, ListStream, PipelineData, PluginSignature, ShellError, Spanned,
Value,
engine::Closure, Config, IntoInterruptiblePipelineData, ListStream, PipelineData,
PluginSignature, ShellError, Spanned, Value,
};
use crate::{
protocol::{
CallInfo, CustomValueOp, PluginCall, PluginCallId, PluginCallResponse, PluginCustomValue,
PluginInput, ProtocolInfo,
CallInfo, CustomValueOp, EngineCall, EngineCallId, EngineCallResponse, PluginCall,
PluginCallId, PluginCallResponse, PluginCustomValue, PluginInput, ProtocolInfo,
},
LabeledError, PluginOutput,
};
@ -47,8 +50,13 @@ mod tests;
/// Internal shared state between the manager and each interface.
struct EngineInterfaceState {
/// Sequence for generating engine call ids
engine_call_id_sequence: Sequence,
/// Sequence for generating stream ids
stream_id_sequence: Sequence,
/// Sender to subscribe to an engine call response
engine_call_subscription_sender:
mpsc::Sender<(EngineCallId, mpsc::Sender<EngineCallResponse<PipelineData>>)>,
/// The synchronized output writer
writer: Box<dyn PluginWrite<PluginOutput>>,
}
@ -56,7 +64,12 @@ struct EngineInterfaceState {
impl std::fmt::Debug for EngineInterfaceState {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("EngineInterfaceState")
.field("engine_call_id_sequence", &self.engine_call_id_sequence)
.field("stream_id_sequence", &self.stream_id_sequence)
.field(
"engine_call_subscription_sender",
&self.engine_call_subscription_sender,
)
.finish_non_exhaustive()
}
}
@ -70,6 +83,12 @@ pub(crate) struct EngineInterfaceManager {
plugin_call_sender: Option<mpsc::Sender<ReceivedPluginCall>>,
/// Receiver for PluginCalls. This is usually taken after initialization
plugin_call_receiver: Option<mpsc::Receiver<ReceivedPluginCall>>,
/// Subscriptions for engine call responses
engine_call_subscriptions:
BTreeMap<EngineCallId, mpsc::Sender<EngineCallResponse<PipelineData>>>,
/// Receiver for engine call subscriptions
engine_call_subscription_receiver:
mpsc::Receiver<(EngineCallId, mpsc::Sender<EngineCallResponse<PipelineData>>)>,
/// Manages stream messages and state
stream_manager: StreamManager,
/// Protocol version info, set after `Hello` received
@ -79,14 +98,19 @@ pub(crate) struct EngineInterfaceManager {
impl EngineInterfaceManager {
pub(crate) fn new(writer: impl PluginWrite<PluginOutput> + 'static) -> EngineInterfaceManager {
let (plug_tx, plug_rx) = mpsc::channel();
let (subscription_tx, subscription_rx) = mpsc::channel();
EngineInterfaceManager {
state: Arc::new(EngineInterfaceState {
engine_call_id_sequence: Sequence::default(),
stream_id_sequence: Sequence::default(),
engine_call_subscription_sender: subscription_tx,
writer: Box::new(writer),
}),
plugin_call_sender: Some(plug_tx),
plugin_call_receiver: Some(plug_rx),
engine_call_subscriptions: BTreeMap::new(),
engine_call_subscription_receiver: subscription_rx,
stream_manager: StreamManager::new(),
protocol_info: None,
}
@ -122,6 +146,38 @@ impl EngineInterfaceManager {
})
}
/// Flush any remaining subscriptions in the receiver into the map
fn receive_engine_call_subscriptions(&mut self) {
for (id, subscription) in self.engine_call_subscription_receiver.try_iter() {
if let btree_map::Entry::Vacant(e) = self.engine_call_subscriptions.entry(id) {
e.insert(subscription);
} else {
log::warn!("Duplicate engine call ID ignored: {id}")
}
}
}
/// Send a [`EngineCallResponse`] to the appropriate sender
fn send_engine_call_response(
&mut self,
id: EngineCallId,
response: EngineCallResponse<PipelineData>,
) -> Result<(), ShellError> {
// Ensure all of the subscriptions have been flushed out of the receiver
self.receive_engine_call_subscriptions();
// Remove the sender - there is only one response per engine call
if let Some(sender) = self.engine_call_subscriptions.remove(&id) {
if sender.send(response).is_err() {
log::warn!("Received an engine call response for id={id}, but the caller hung up");
}
Ok(())
} else {
Err(ShellError::PluginFailedToDecode {
msg: format!("Unknown engine call ID: {id}"),
})
}
}
/// True if there are no other copies of the state (which would mean there are no interfaces
/// and no stream readers/writers)
pub(crate) fn is_finished(&self) -> bool {
@ -141,7 +197,13 @@ impl EngineInterfaceManager {
}
if let Err(err) = msg.and_then(|msg| self.consume(msg)) {
// Error to streams
let _ = self.stream_manager.broadcast_read_error(err.clone());
// Error to engine call waiters
self.receive_engine_call_subscriptions();
for sender in std::mem::take(&mut self.engine_call_subscriptions).into_values() {
let _ = sender.send(EngineCallResponse::Error(err.clone()));
}
return Err(err);
}
}
@ -200,7 +262,6 @@ impl InterfaceManager for EngineInterfaceManager {
name,
mut call,
input,
config,
}) => {
let interface = self.interface_for_context(id);
// If there's an error with initialization of the input stream, just send
@ -214,12 +275,7 @@ impl InterfaceManager for EngineInterfaceManager {
// Send the plugin call to the receiver
self.send_plugin_call(ReceivedPluginCall::Run {
engine: interface,
call: CallInfo {
name,
call,
input,
config,
},
call: CallInfo { name, call, input },
})
}
err @ Err(_) => interface.write_response(err)?.write(),
@ -239,6 +295,21 @@ impl InterfaceManager for EngineInterfaceManager {
drop(self.plugin_call_sender.take());
Ok(())
}
PluginInput::EngineCallResponse(id, response) => {
let response = match response {
EngineCallResponse::Error(err) => EngineCallResponse::Error(err),
EngineCallResponse::Config(config) => EngineCallResponse::Config(config),
EngineCallResponse::PipelineData(header) => {
// If there's an error with initializing this stream, change it to an engine
// call error response, but send it anyway
match self.read_pipeline_data(header, None) {
Ok(data) => EngineCallResponse::PipelineData(data),
Err(err) => EngineCallResponse::Error(err),
}
}
};
self.send_engine_call_response(id, response)
}
}
}
@ -341,6 +412,264 @@ impl EngineInterface {
self.write(PluginOutput::CallResponse(self.context()?, response))?;
self.flush()
}
/// Write an engine call message. Returns the writer for the stream, and the receiver for
/// the response to the engine call.
fn write_engine_call(
&self,
call: EngineCall<PipelineData>,
) -> Result<
(
PipelineDataWriter<Self>,
mpsc::Receiver<EngineCallResponse<PipelineData>>,
),
ShellError,
> {
let context = self.context()?;
let id = self.state.engine_call_id_sequence.next()?;
let (tx, rx) = mpsc::channel();
// Convert the call into one with a header and handle the stream, if necessary
let (call, writer) = match call {
EngineCall::EvalClosure {
closure,
positional,
input,
redirect_stdout,
redirect_stderr,
} => {
let (header, writer) = self.init_write_pipeline_data(input)?;
(
EngineCall::EvalClosure {
closure,
positional,
input: header,
redirect_stdout,
redirect_stderr,
},
writer,
)
}
// These calls have no pipeline data, so they're just the same on both sides
EngineCall::GetConfig => (EngineCall::GetConfig, Default::default()),
EngineCall::GetPluginConfig => (EngineCall::GetPluginConfig, Default::default()),
};
// Register the channel
self.state
.engine_call_subscription_sender
.send((id, tx))
.map_err(|_| ShellError::NushellFailed {
msg: "EngineInterfaceManager hung up and is no longer accepting engine calls"
.into(),
})?;
// Write request
self.write(PluginOutput::EngineCall { context, id, call })?;
self.flush()?;
Ok((writer, rx))
}
/// Perform an engine call. Input and output streams are handled.
fn engine_call(
&self,
call: EngineCall<PipelineData>,
) -> Result<EngineCallResponse<PipelineData>, ShellError> {
let (writer, rx) = self.write_engine_call(call)?;
// Finish writing stream in the background
writer.write_background()?;
// Wait on receiver to get the response
rx.recv().map_err(|_| ShellError::NushellFailed {
msg: "Failed to get response to engine call because the channel was closed".into(),
})
}
/// Get the full shell configuration from the engine. As this is quite a large object, it is
/// provided on request only.
///
/// # Example
///
/// Format a value in the user's preferred way:
///
/// ```
/// # use nu_protocol::{Value, ShellError};
/// # use nu_plugin::EngineInterface;
/// # fn example(engine: &EngineInterface, value: &Value) -> Result<(), ShellError> {
/// let config = engine.get_config()?;
/// eprintln!("{}", value.to_expanded_string(", ", &config));
/// # Ok(())
/// # }
/// ```
pub fn get_config(&self) -> Result<Box<Config>, ShellError> {
match self.engine_call(EngineCall::GetConfig)? {
EngineCallResponse::Config(config) => Ok(config),
EngineCallResponse::Error(err) => Err(err),
_ => Err(ShellError::PluginFailedToDecode {
msg: "Received unexpected response for EngineCall::GetConfig".into(),
}),
}
}
/// Get the plugin-specific configuration from the engine. This lives in
/// `$env.config.plugins.NAME` for a plugin named `NAME`. If the config is set to a closure,
/// it is automatically evaluated each time.
///
/// # Example
///
/// Print this plugin's config:
///
/// ```
/// # use nu_protocol::{Value, ShellError};
/// # use nu_plugin::EngineInterface;
/// # fn example(engine: &EngineInterface, value: &Value) -> Result<(), ShellError> {
/// let config = engine.get_plugin_config()?;
/// eprintln!("{:?}", config);
/// # Ok(())
/// # }
/// ```
pub fn get_plugin_config(&self) -> Result<Option<Value>, ShellError> {
match self.engine_call(EngineCall::GetPluginConfig)? {
EngineCallResponse::PipelineData(PipelineData::Empty) => Ok(None),
EngineCallResponse::PipelineData(PipelineData::Value(value, _)) => Ok(Some(value)),
EngineCallResponse::Error(err) => Err(err),
_ => Err(ShellError::PluginFailedToDecode {
msg: "Received unexpected response for EngineCall::GetConfig".into(),
}),
}
}
/// Ask the engine to evaluate a closure. Input to the closure is passed as a stream, and the
/// output is available as a stream.
///
/// Set `redirect_stdout` to `true` to capture the standard output stream of an external
/// command, if the closure results in an external command.
///
/// Set `redirect_stderr` to `true` to capture the standard error stream of an external command,
/// if the closure results in an external command.
///
/// # Example
///
/// Invoked as:
///
/// ```nushell
/// my_command { seq 1 $in | each { |n| $"Hello, ($n)" } }
/// ```
///
/// ```
/// # use nu_protocol::{Value, ShellError, PipelineData};
/// # use nu_plugin::{EngineInterface, EvaluatedCall};
/// # fn example(engine: &EngineInterface, call: &EvaluatedCall) -> Result<(), ShellError> {
/// let closure = call.req(0)?;
/// let input = PipelineData::Value(Value::int(4, call.head), None);
/// let output = engine.eval_closure_with_stream(
/// &closure,
/// vec![],
/// input,
/// true,
/// false,
/// )?;
/// for value in output {
/// eprintln!("Closure says: {}", value.as_str()?);
/// }
/// # Ok(())
/// # }
/// ```
///
/// Output:
///
/// ```text
/// Closure says: Hello, 1
/// Closure says: Hello, 2
/// Closure says: Hello, 3
/// Closure says: Hello, 4
/// ```
pub fn eval_closure_with_stream(
&self,
closure: &Spanned<Closure>,
mut positional: Vec<Value>,
input: PipelineData,
redirect_stdout: bool,
redirect_stderr: bool,
) -> Result<PipelineData, ShellError> {
// Ensure closure args have custom values serialized
positional
.iter_mut()
.try_for_each(PluginCustomValue::serialize_custom_values_in)?;
let call = EngineCall::EvalClosure {
closure: closure.clone(),
positional,
input,
redirect_stdout,
redirect_stderr,
};
match self.engine_call(call)? {
EngineCallResponse::Error(error) => Err(error),
EngineCallResponse::PipelineData(data) => Ok(data),
_ => Err(ShellError::PluginFailedToDecode {
msg: "Received unexpected response type for EngineCall::EvalClosure".into(),
}),
}
}
/// Ask the engine to evaluate a closure. Input is optionally passed as a [`Value`], and output
/// of the closure is collected to a [`Value`] even if it is a stream.
///
/// If the closure results in an external command, the return value will be a collected string
/// or binary value of the standard output stream of that command, similar to calling
/// [`eval_closure_with_stream()`](Self::eval_closure_with_stream) with `redirect_stdout` =
/// `true` and `redirect_stderr` = `false`.
///
/// Use [`eval_closure_with_stream()`](Self::eval_closure_with_stream) if more control over the
/// input and output is desired.
///
/// # Example
///
/// Invoked as:
///
/// ```nushell
/// my_command { |number| $number + 1}
/// ```
///
/// ```
/// # use nu_protocol::{Value, ShellError};
/// # use nu_plugin::{EngineInterface, EvaluatedCall};
/// # fn example(engine: &EngineInterface, call: &EvaluatedCall) -> Result<(), ShellError> {
/// let closure = call.req(0)?;
/// for n in 0..4 {
/// let result = engine.eval_closure(&closure, vec![Value::int(n, call.head)], None)?;
/// eprintln!("{} => {}", n, result.as_int()?);
/// }
/// # Ok(())
/// # }
/// ```
///
/// Output:
///
/// ```text
/// 0 => 1
/// 1 => 2
/// 2 => 3
/// 3 => 4
/// ```
pub fn eval_closure(
&self,
closure: &Spanned<Closure>,
positional: Vec<Value>,
input: Option<Value>,
) -> Result<Value, ShellError> {
let input = input.map_or_else(|| PipelineData::Empty, |v| PipelineData::Value(v, None));
let output = self.eval_closure_with_stream(closure, positional, input, true, false)?;
// Unwrap an error value
match output.into_value(closure.span) {
Value::Error { error, .. } => Err(*error),
value => Ok(value),
}
}
}
impl Interface for EngineInterface {

View File

@ -1,22 +1,22 @@
use std::sync::mpsc::TryRecvError;
use std::sync::mpsc::{self, TryRecvError};
use nu_protocol::{
CustomValue, IntoInterruptiblePipelineData, PipelineData, PluginSignature, ShellError, Span,
Spanned, Value,
engine::Closure, Config, CustomValue, IntoInterruptiblePipelineData, PipelineData,
PluginSignature, ShellError, Span, Spanned, Value,
};
use crate::{
plugin::interface::{test_util::TestCase, Interface, InterfaceManager},
protocol::{
test_util::{expected_test_custom_value, test_plugin_custom_value, TestCustomValue},
CallInfo, CustomValueOp, ExternalStreamInfo, ListStreamInfo, PipelineDataHeader,
PluginCall, PluginCustomValue, PluginInput, Protocol, ProtocolInfo, RawStreamInfo,
StreamData, StreamMessage,
CallInfo, CustomValueOp, EngineCall, EngineCallId, EngineCallResponse, ExternalStreamInfo,
ListStreamInfo, PipelineDataHeader, PluginCall, PluginCustomValue, PluginInput, Protocol,
ProtocolInfo, RawStreamInfo, StreamData, StreamMessage,
},
EvaluatedCall, LabeledError, PluginCallResponse, PluginOutput,
};
use super::ReceivedPluginCall;
use super::{EngineInterfaceManager, ReceivedPluginCall};
#[test]
fn manager_consume_all_consumes_messages() -> Result<(), ShellError> {
@ -90,7 +90,7 @@ fn check_test_io_error(error: &ShellError) {
}
#[test]
fn manager_consume_all_propagates_error_to_readers() -> Result<(), ShellError> {
fn manager_consume_all_propagates_io_error_to_readers() -> Result<(), ShellError> {
let mut test = TestCase::new();
let mut manager = test.engine();
@ -170,6 +170,74 @@ fn manager_consume_all_propagates_message_error_to_readers() -> Result<(), Shell
}
}
fn fake_engine_call(
manager: &mut EngineInterfaceManager,
id: EngineCallId,
) -> mpsc::Receiver<EngineCallResponse<PipelineData>> {
// Set up a fake engine call subscription
let (tx, rx) = mpsc::channel();
manager.engine_call_subscriptions.insert(id, tx);
rx
}
#[test]
fn manager_consume_all_propagates_io_error_to_engine_calls() -> Result<(), ShellError> {
let mut test = TestCase::new();
let mut manager = test.engine();
let interface = manager.get_interface();
test.set_read_error(test_io_error());
// Set up a fake engine call subscription
let rx = fake_engine_call(&mut manager, 0);
manager
.consume_all(&mut test)
.expect_err("consume_all did not error");
// We have to hold interface until now otherwise consume_all won't try to process the message
drop(interface);
let message = rx.try_recv().expect("failed to get engine call message");
match message {
EngineCallResponse::Error(error) => {
check_test_io_error(&error);
Ok(())
}
_ => panic!("received something other than an error: {message:?}"),
}
}
#[test]
fn manager_consume_all_propagates_message_error_to_engine_calls() -> Result<(), ShellError> {
let mut test = TestCase::new();
let mut manager = test.engine();
let interface = manager.get_interface();
test.add(invalid_input());
// Set up a fake engine call subscription
let rx = fake_engine_call(&mut manager, 0);
manager
.consume_all(&mut test)
.expect_err("consume_all did not error");
// We have to hold interface until now otherwise consume_all won't try to process the message
drop(interface);
let message = rx.try_recv().expect("failed to get engine call message");
match message {
EngineCallResponse::Error(error) => {
check_invalid_input_error(&error);
Ok(())
}
_ => panic!("received something other than an error: {message:?}"),
}
}
#[test]
fn manager_consume_sets_protocol_info_on_hello() -> Result<(), ShellError> {
let mut manager = TestCase::new().engine();
@ -275,7 +343,6 @@ fn manager_consume_call_run_forwards_to_receiver_with_context() -> Result<(), Sh
named: vec![],
},
input: PipelineDataHeader::Empty,
config: None,
}),
))?;
@ -310,7 +377,6 @@ fn manager_consume_call_run_forwards_to_receiver_with_pipeline_data() -> Result<
named: vec![],
},
input: PipelineDataHeader::ListStream(ListStreamInfo { id: 6 }),
config: None,
}),
))?;
@ -364,7 +430,6 @@ fn manager_consume_call_run_deserializes_custom_values_in_args() -> Result<(), S
)],
},
input: PipelineDataHeader::Empty,
config: None,
}),
))?;
@ -443,6 +508,43 @@ fn manager_consume_call_custom_value_op_forwards_to_receiver_with_context() -> R
Ok(())
}
#[test]
fn manager_consume_engine_call_response_forwards_to_subscriber_with_pipeline_data(
) -> Result<(), ShellError> {
let mut manager = TestCase::new().engine();
manager.protocol_info = Some(ProtocolInfo::default());
let rx = fake_engine_call(&mut manager, 0);
manager.consume(PluginInput::EngineCallResponse(
0,
EngineCallResponse::PipelineData(PipelineDataHeader::ListStream(ListStreamInfo { id: 0 })),
))?;
for i in 0..2 {
manager.consume(PluginInput::Stream(StreamMessage::Data(
0,
Value::test_int(i).into(),
)))?;
}
manager.consume(PluginInput::Stream(StreamMessage::End(0)))?;
// Make sure the streams end and we don't deadlock
drop(manager);
let response = rx.try_recv().expect("failed to get engine call response");
match response {
EngineCallResponse::PipelineData(data) => {
// Ensure we manage to receive the stream messages
assert_eq!(2, data.into_iter().count());
Ok(())
}
_ => panic!("unexpected response: {response:?}"),
}
}
#[test]
fn manager_prepare_pipeline_data_deserializes_custom_values() -> Result<(), ShellError> {
let manager = TestCase::new().engine();
@ -683,6 +785,166 @@ fn interface_write_signature() -> Result<(), ShellError> {
Ok(())
}
#[test]
fn interface_write_engine_call_registers_subscription() -> Result<(), ShellError> {
let mut manager = TestCase::new().engine();
assert!(
manager.engine_call_subscriptions.is_empty(),
"engine call subscriptions not empty before start of test"
);
let interface = manager.interface_for_context(0);
let _ = interface.write_engine_call(EngineCall::GetConfig)?;
manager.receive_engine_call_subscriptions();
assert!(
!manager.engine_call_subscriptions.is_empty(),
"not registered"
);
Ok(())
}
#[test]
fn interface_write_engine_call_writes_with_correct_context() -> Result<(), ShellError> {
let test = TestCase::new();
let manager = test.engine();
let interface = manager.interface_for_context(32);
let _ = interface.write_engine_call(EngineCall::GetConfig)?;
match test.next_written().expect("nothing written") {
PluginOutput::EngineCall { context, call, .. } => {
assert_eq!(32, context, "context incorrect");
assert!(
matches!(call, EngineCall::GetConfig),
"incorrect engine call (expected GetConfig): {call:?}"
);
}
other => panic!("incorrect output: {other:?}"),
}
assert!(!test.has_unconsumed_write());
Ok(())
}
/// Fake responses to requests for engine call messages
fn start_fake_plugin_call_responder(
manager: EngineInterfaceManager,
take: usize,
mut f: impl FnMut(EngineCallId) -> EngineCallResponse<PipelineData> + Send + 'static,
) {
std::thread::Builder::new()
.name("fake engine call responder".into())
.spawn(move || {
for (id, sub) in manager
.engine_call_subscription_receiver
.into_iter()
.take(take)
{
sub.send(f(id)).expect("failed to send");
}
})
.expect("failed to spawn thread");
}
#[test]
fn interface_get_config() -> Result<(), ShellError> {
let test = TestCase::new();
let manager = test.engine();
let interface = manager.interface_for_context(0);
start_fake_plugin_call_responder(manager, 1, |_| {
EngineCallResponse::Config(Config::default().into())
});
let _ = interface.get_config()?;
assert!(test.has_unconsumed_write());
Ok(())
}
#[test]
fn interface_get_plugin_config() -> Result<(), ShellError> {
let test = TestCase::new();
let manager = test.engine();
let interface = manager.interface_for_context(0);
start_fake_plugin_call_responder(manager, 2, |id| {
if id == 0 {
EngineCallResponse::PipelineData(PipelineData::Empty)
} else {
EngineCallResponse::PipelineData(PipelineData::Value(Value::test_int(2), None))
}
});
let first_config = interface.get_plugin_config()?;
assert!(first_config.is_none(), "should be None: {first_config:?}");
let second_config = interface.get_plugin_config()?;
assert_eq!(Some(Value::test_int(2)), second_config);
assert!(test.has_unconsumed_write());
Ok(())
}
#[test]
fn interface_eval_closure_with_stream() -> Result<(), ShellError> {
let test = TestCase::new();
let manager = test.engine();
let interface = manager.interface_for_context(0);
start_fake_plugin_call_responder(manager, 1, |_| {
EngineCallResponse::PipelineData(PipelineData::Value(Value::test_int(2), None))
});
let result = interface
.eval_closure_with_stream(
&Spanned {
item: Closure {
block_id: 42,
captures: vec![(0, Value::test_int(5))],
},
span: Span::test_data(),
},
vec![Value::test_string("test")],
PipelineData::Empty,
true,
false,
)?
.into_value(Span::test_data());
assert_eq!(Value::test_int(2), result);
// Double check the message that was written, as it's complicated
match test.next_written().expect("nothing written") {
PluginOutput::EngineCall { call, .. } => match call {
EngineCall::EvalClosure {
closure,
positional,
input,
redirect_stdout,
redirect_stderr,
} => {
assert_eq!(42, closure.item.block_id, "closure.item.block_id");
assert_eq!(1, closure.item.captures.len(), "closure.item.captures.len");
assert_eq!(
(0, Value::test_int(5)),
closure.item.captures[0],
"closure.item.captures[0]"
);
assert_eq!(Span::test_data(), closure.span, "closure.span");
assert_eq!(1, positional.len(), "positional.len");
assert_eq!(Value::test_string("test"), positional[0], "positional[0]");
assert!(matches!(input, PipelineDataHeader::Empty));
assert!(redirect_stdout);
assert!(!redirect_stderr);
}
_ => panic!("wrong engine call: {call:?}"),
},
other => panic!("wrong output: {other:?}"),
}
Ok(())
}
#[test]
fn interface_prepare_pipeline_data_serializes_custom_values() -> Result<(), ShellError> {
let interface = TestCase::new().engine().get_interface();

View File

@ -13,8 +13,9 @@ use nu_protocol::{
use crate::{
plugin::{context::PluginExecutionContext, PluginIdentity},
protocol::{
CallInfo, CustomValueOp, PluginCall, PluginCallId, PluginCallResponse, PluginCustomValue,
PluginInput, PluginOutput, ProtocolInfo,
CallInfo, CustomValueOp, EngineCall, EngineCallId, EngineCallResponse, PluginCall,
PluginCallId, PluginCallResponse, PluginCustomValue, PluginInput, PluginOutput,
ProtocolInfo, StreamId, StreamMessage,
},
sequence::Sequence,
};
@ -34,6 +35,12 @@ enum ReceivedPluginCallMessage {
/// An critical error with the interface
Error(ShellError),
/// An engine call that should be evaluated and responded to, but is not the final response
///
/// We send this back to the thread that made the plugin call so we don't block the reader
/// thread
EngineCall(EngineCallId, EngineCall<PipelineData>),
}
/// Context for plugin call execution
@ -87,9 +94,11 @@ impl std::fmt::Debug for PluginInterfaceState {
#[derive(Debug)]
struct PluginCallSubscription {
/// The sender back to the thread that is waiting for the plugin call response
sender: mpsc::Sender<ReceivedPluginCallMessage>,
/// Optional context for the environment of a plugin call
sender: Option<mpsc::Sender<ReceivedPluginCallMessage>>,
/// Optional context for the environment of a plugin call for servicing engine calls
context: Option<Context>,
/// Number of streams that still need to be read from the plugin call response
remaining_streams_to_read: i32,
}
/// Manages reading and dispatching messages for [`PluginInterface`]s.
@ -105,6 +114,10 @@ pub(crate) struct PluginInterfaceManager {
plugin_call_subscriptions: BTreeMap<PluginCallId, PluginCallSubscription>,
/// Receiver for plugin call subscriptions
plugin_call_subscription_receiver: mpsc::Receiver<(PluginCallId, PluginCallSubscription)>,
/// Tracker for which plugin call streams being read belong to
///
/// This is necessary so we know when we can remove context for plugin calls
plugin_call_input_streams: BTreeMap<StreamId, PluginCallId>,
}
impl PluginInterfaceManager {
@ -126,6 +139,7 @@ impl PluginInterfaceManager {
protocol_info: None,
plugin_call_subscriptions: BTreeMap::new(),
plugin_call_subscription_receiver: subscription_rx,
plugin_call_input_streams: BTreeMap::new(),
}
}
@ -140,6 +154,29 @@ impl PluginInterfaceManager {
}
}
/// Track the start of stream(s)
fn recv_stream_started(&mut self, call_id: PluginCallId, stream_id: StreamId) {
self.receive_plugin_call_subscriptions();
if let Some(sub) = self.plugin_call_subscriptions.get_mut(&call_id) {
self.plugin_call_input_streams.insert(stream_id, call_id);
sub.remaining_streams_to_read += 1;
}
}
/// Track the end of a stream
fn recv_stream_ended(&mut self, stream_id: StreamId) {
if let Some(call_id) = self.plugin_call_input_streams.remove(&stream_id) {
if let btree_map::Entry::Occupied(mut e) = self.plugin_call_subscriptions.entry(call_id)
{
e.get_mut().remaining_streams_to_read -= 1;
// Remove the subscription if there are no more streams to be read.
if e.get().remaining_streams_to_read <= 0 {
e.remove();
}
}
}
}
/// Find the context corresponding to the given plugin call id
fn get_context(&mut self, id: PluginCallId) -> Result<Option<Context>, ShellError> {
// Make sure we're up to date
@ -162,15 +199,22 @@ impl PluginInterfaceManager {
// Ensure we're caught up on the subscriptions made
self.receive_plugin_call_subscriptions();
// Remove the subscription, since this would be the last message
if let Some(subscription) = self.plugin_call_subscriptions.remove(&id) {
if subscription
if let btree_map::Entry::Occupied(mut e) = self.plugin_call_subscriptions.entry(id) {
// Remove the subscription sender, since this will be the last message.
//
// We can spawn a new one if we need it for engine calls.
if e.get_mut()
.sender
.send(ReceivedPluginCallMessage::Response(response))
.is_err()
.take()
.and_then(|s| s.send(ReceivedPluginCallMessage::Response(response)).ok())
.is_none()
{
log::warn!("Received a plugin call response for id={id}, but the caller hung up");
}
// If there are no registered streams, just remove it
if e.get().remaining_streams_to_read <= 0 {
e.remove();
}
Ok(())
} else {
Err(ShellError::PluginFailedToDecode {
@ -179,6 +223,106 @@ impl PluginInterfaceManager {
}
}
/// Spawn a handler for engine calls for a plugin, in case we need to handle engine calls
/// after the response has already been received (in which case we have nowhere to send them)
fn spawn_engine_call_handler(
&mut self,
id: PluginCallId,
) -> Result<&mpsc::Sender<ReceivedPluginCallMessage>, ShellError> {
let interface = self.get_interface();
if let Some(sub) = self.plugin_call_subscriptions.get_mut(&id) {
if sub.sender.is_none() {
let (tx, rx) = mpsc::channel();
let context = sub.context.clone();
let handler = move || {
for msg in rx {
// This thread only handles engine calls.
match msg {
ReceivedPluginCallMessage::EngineCall(engine_call_id, engine_call) => {
if let Err(err) = interface.handle_engine_call(
engine_call_id,
engine_call,
&context,
) {
log::warn!(
"Error in plugin post-response engine call handler: \
{err:?}"
);
return;
}
}
other => log::warn!(
"Bad message received in plugin post-response \
engine call handler: {other:?}"
),
}
}
};
std::thread::Builder::new()
.name("plugin engine call handler".into())
.spawn(handler)
.expect("failed to spawn thread");
sub.sender = Some(tx);
Ok(sub.sender.as_ref().unwrap_or_else(|| unreachable!()))
} else {
Err(ShellError::NushellFailed {
msg: "Tried to spawn the fallback engine call handler before the plugin call \
response had been received"
.into(),
})
}
} else {
Err(ShellError::NushellFailed {
msg: format!("Couldn't find plugin ID={id} in subscriptions"),
})
}
}
/// Send an [`EngineCall`] to the appropriate sender
fn send_engine_call(
&mut self,
plugin_call_id: PluginCallId,
engine_call_id: EngineCallId,
call: EngineCall<PipelineData>,
) -> Result<(), ShellError> {
// Ensure we're caught up on the subscriptions made
self.receive_plugin_call_subscriptions();
// Don't remove the sender, as there could be more calls or responses
if let Some(subscription) = self.plugin_call_subscriptions.get(&plugin_call_id) {
let msg = ReceivedPluginCallMessage::EngineCall(engine_call_id, call);
// Call if there's an error sending the engine call
let send_error = |this: &Self| {
log::warn!(
"Received an engine call for plugin_call_id={plugin_call_id}, \
but the caller hung up"
);
// We really have no choice here but to send the response ourselves and hope we
// don't block
this.state.writer.write(&PluginInput::EngineCallResponse(
engine_call_id,
EngineCallResponse::Error(ShellError::IOError {
msg: "Can't make engine call because the original caller hung up".into(),
}),
))?;
this.state.writer.flush()
};
// Try to send to the sender if it exists
if let Some(sender) = subscription.sender.as_ref() {
sender.send(msg).or_else(|_| send_error(self))
} else {
// The sender no longer exists. Spawn a specific one just for engine calls
let sender = self.spawn_engine_call_handler(plugin_call_id)?;
sender.send(msg).or_else(|_| send_error(self))
}
} else {
Err(ShellError::PluginFailedToDecode {
msg: format!("Unknown plugin call ID: {plugin_call_id}"),
})
}
}
/// True if there are no other copies of the state (which would mean there are no interfaces
/// and no stream readers/writers)
pub(crate) fn is_finished(&self) -> bool {
@ -207,7 +351,8 @@ impl PluginInterfaceManager {
{
let _ = subscription
.sender
.send(ReceivedPluginCallMessage::Error(err.clone()));
.as_ref()
.map(|s| s.send(ReceivedPluginCallMessage::Error(err.clone())));
}
return Err(err);
}
@ -268,6 +413,10 @@ impl InterfaceManager for PluginInterfaceManager {
// error response, but send it anyway
let exec_context = self.get_context(id)?;
let ctrlc = exec_context.as_ref().and_then(|c| c.0.ctrlc());
// Register the streams in the response
for stream_id in data.stream_ids() {
self.recv_stream_started(id, stream_id);
}
match self.read_pipeline_data(data, ctrlc) {
Ok(data) => PluginCallResponse::PipelineData(data),
Err(err) => PluginCallResponse::Error(err.into()),
@ -276,6 +425,42 @@ impl InterfaceManager for PluginInterfaceManager {
};
self.send_plugin_call_response(id, response)
}
PluginOutput::EngineCall { context, id, call } => {
// Handle reading the pipeline data, if any
let exec_context = self.get_context(context)?;
let ctrlc = exec_context.as_ref().and_then(|c| c.0.ctrlc());
let call = match call {
EngineCall::GetConfig => Ok(EngineCall::GetConfig),
EngineCall::GetPluginConfig => Ok(EngineCall::GetPluginConfig),
EngineCall::EvalClosure {
closure,
mut positional,
input,
redirect_stdout,
redirect_stderr,
} => {
// Add source to any plugin custom values in the arguments
for arg in positional.iter_mut() {
PluginCustomValue::add_source(arg, &self.state.identity);
}
self.read_pipeline_data(input, ctrlc)
.map(|input| EngineCall::EvalClosure {
closure,
positional,
input,
redirect_stdout,
redirect_stderr,
})
}
};
match call {
Ok(call) => self.send_engine_call(context, id, call),
// If there was an error with setting up the call, just write the error
Err(err) => self
.get_interface()
.write_engine_call_response(id, EngineCallResponse::Error(err)),
}
}
}
}
@ -302,6 +487,14 @@ impl InterfaceManager for PluginInterfaceManager {
PipelineData::Empty | PipelineData::ExternalStream { .. } => Ok(data),
}
}
fn consume_stream_message(&mut self, message: StreamMessage) -> Result<(), ShellError> {
// Keep track of streams that end so we know if we don't need the context anymore
if let StreamMessage::End(id) = message {
self.recv_stream_ended(id);
}
self.stream_manager.handle_message(message)
}
}
/// A reference through which a plugin can be interacted with during execution.
@ -330,8 +523,38 @@ impl PluginInterface {
self.flush()
}
/// Write an [`EngineCallResponse`]. Writes the full stream contained in any [`PipelineData`]
/// before returning.
pub(crate) fn write_engine_call_response(
&self,
id: EngineCallId,
response: EngineCallResponse<PipelineData>,
) -> Result<(), ShellError> {
// Set up any stream if necessary
let (response, writer) = match response {
EngineCallResponse::PipelineData(data) => {
let (header, writer) = self.init_write_pipeline_data(data)?;
(EngineCallResponse::PipelineData(header), Some(writer))
}
// No pipeline data:
EngineCallResponse::Error(err) => (EngineCallResponse::Error(err), None),
EngineCallResponse::Config(config) => (EngineCallResponse::Config(config), None),
};
// Write the response, including the pipeline data header if present
self.write(PluginInput::EngineCallResponse(id, response))?;
self.flush()?;
// If we have a stream to write, do it now
if let Some(writer) = writer {
writer.write_background()?;
}
Ok(())
}
/// Write a plugin call message. Returns the writer for the stream, and the receiver for
/// messages (e.g. response) related to the plugin call
/// messages - i.e. response and engine calls - related to the plugin call
fn write_plugin_call(
&self,
call: PluginCall<PipelineData>,
@ -354,17 +577,16 @@ impl PluginInterface {
}
PluginCall::Run(CallInfo {
name,
call,
mut call,
input,
config,
}) => {
verify_call_args(&mut call, &self.state.identity)?;
let (header, writer) = self.init_write_pipeline_data(input)?;
(
PluginCall::Run(CallInfo {
name,
call,
input: header,
config,
}),
writer,
)
@ -377,8 +599,9 @@ impl PluginInterface {
.send((
id,
PluginCallSubscription {
sender: tx,
sender: Some(tx),
context,
remaining_streams_to_read: 0,
},
))
.map_err(|_| ShellError::NushellFailed {
@ -397,22 +620,62 @@ impl PluginInterface {
fn receive_plugin_call_response(
&self,
rx: mpsc::Receiver<ReceivedPluginCallMessage>,
context: &Option<Context>,
) -> Result<PluginCallResponse<PipelineData>, ShellError> {
if let Ok(msg) = rx.recv() {
// Handle message from receiver
// Handle message from receiver
for msg in rx {
match msg {
ReceivedPluginCallMessage::Response(resp) => Ok(resp),
ReceivedPluginCallMessage::Error(err) => Err(err),
ReceivedPluginCallMessage::Response(resp) => {
return Ok(resp);
}
ReceivedPluginCallMessage::Error(err) => {
return Err(err);
}
ReceivedPluginCallMessage::EngineCall(engine_call_id, engine_call) => {
self.handle_engine_call(engine_call_id, engine_call, context)?;
}
}
} else {
// If we fail to get a response
Err(ShellError::PluginFailedToDecode {
msg: "Failed to receive response to plugin call".into(),
})
}
// If we fail to get a response
Err(ShellError::PluginFailedToDecode {
msg: "Failed to receive response to plugin call".into(),
})
}
/// Perform a plugin call. Input and output streams are handled automatically.
/// Handle an engine call and write the response.
fn handle_engine_call(
&self,
engine_call_id: EngineCallId,
engine_call: EngineCall<PipelineData>,
context: &Option<Context>,
) -> Result<(), ShellError> {
let resp =
handle_engine_call(engine_call, context).unwrap_or_else(EngineCallResponse::Error);
// Handle stream
let (resp, writer) = match resp {
EngineCallResponse::Error(error) => (EngineCallResponse::Error(error), None),
EngineCallResponse::Config(config) => (EngineCallResponse::Config(config), None),
EngineCallResponse::PipelineData(data) => {
match self.init_write_pipeline_data(data) {
Ok((header, writer)) => {
(EngineCallResponse::PipelineData(header), Some(writer))
}
// just respond with the error if we fail to set it up
Err(err) => (EngineCallResponse::Error(err), None),
}
}
};
// Write the response, then the stream
self.write(PluginInput::EngineCallResponse(engine_call_id, resp))?;
self.flush()?;
if let Some(writer) = writer {
writer.write_background()?;
}
Ok(())
}
/// Perform a plugin call. Input and output streams are handled, and engine calls are handled
/// too if there are any before the final response.
fn plugin_call(
&self,
call: PluginCall<PipelineData>,
@ -423,7 +686,7 @@ impl PluginInterface {
// Finish writing stream in the background
writer.write_background()?;
self.receive_plugin_call_response(rx)
self.receive_plugin_call_response(rx, context)
}
/// Get the command signatures from the plugin.
@ -471,6 +734,20 @@ impl PluginInterface {
}
}
/// Check that custom values in call arguments come from the right source
fn verify_call_args(
call: &mut crate::EvaluatedCall,
source: &Arc<PluginIdentity>,
) -> Result<(), ShellError> {
for arg in call.positional.iter_mut() {
PluginCustomValue::verify_source(arg, source)?;
}
for arg in call.named.iter_mut().flat_map(|(_, arg)| arg.as_mut()) {
PluginCustomValue::verify_source(arg, source)?;
}
Ok(())
}
impl Interface for PluginInterface {
type Output = PluginInput;
@ -529,3 +806,44 @@ impl Drop for PluginInterface {
}
}
}
/// Handle an engine call.
pub(crate) fn handle_engine_call(
call: EngineCall<PipelineData>,
context: &Option<Context>,
) -> Result<EngineCallResponse<PipelineData>, ShellError> {
let call_name = call.name();
let require_context = || {
context.as_ref().ok_or_else(|| ShellError::GenericError {
error: "A plugin execution context is required for this engine call".into(),
msg: format!(
"attempted to call {} outside of a command invocation",
call_name
),
span: None,
help: Some("this is probably a bug with the plugin".into()),
inner: vec![],
})
};
match call {
EngineCall::GetConfig => {
let context = require_context()?;
let config = Box::new(context.get_config()?);
Ok(EngineCallResponse::Config(config))
}
EngineCall::GetPluginConfig => {
let context = require_context()?;
let plugin_config = context.get_plugin_config()?;
Ok(plugin_config.map_or_else(EngineCallResponse::empty, EngineCallResponse::value))
}
EngineCall::EvalClosure {
closure,
positional,
input,
redirect_stdout,
redirect_stderr,
} => require_context()?
.eval_closure(closure, positional, input, redirect_stdout, redirect_stderr)
.map(EngineCallResponse::PipelineData),
}
}

View File

@ -1,7 +1,11 @@
use std::sync::mpsc;
use std::{
sync::{mpsc, Arc},
time::Duration,
};
use nu_protocol::{
IntoInterruptiblePipelineData, PipelineData, PluginSignature, ShellError, Span, Spanned, Value,
engine::Closure, IntoInterruptiblePipelineData, PipelineData, PluginSignature, ShellError,
Span, Spanned, Value,
};
use crate::{
@ -12,15 +16,16 @@ use crate::{
},
protocol::{
test_util::{expected_test_custom_value, test_plugin_custom_value},
CallInfo, CustomValueOp, ExternalStreamInfo, ListStreamInfo, PipelineDataHeader,
PluginCall, PluginCallId, PluginCustomValue, PluginInput, Protocol, ProtocolInfo,
RawStreamInfo, StreamData, StreamMessage,
CallInfo, CustomValueOp, EngineCall, EngineCallResponse, ExternalStreamInfo,
ListStreamInfo, PipelineDataHeader, PluginCall, PluginCallId, PluginCustomValue,
PluginInput, Protocol, ProtocolInfo, RawStreamInfo, StreamData, StreamMessage,
},
EvaluatedCall, PluginCallResponse, PluginOutput,
};
use super::{
PluginCallSubscription, PluginInterface, PluginInterfaceManager, ReceivedPluginCallMessage,
Context, PluginCallSubscription, PluginInterface, PluginInterfaceManager,
ReceivedPluginCallMessage,
};
#[test]
@ -185,8 +190,9 @@ fn fake_plugin_call(
manager.plugin_call_subscriptions.insert(
id,
PluginCallSubscription {
sender: tx,
sender: Some(tx),
context: None,
remaining_streams_to_read: 0,
},
);
@ -338,6 +344,282 @@ fn manager_consume_call_response_forwards_to_subscriber_with_pipeline_data(
}
}
#[test]
fn manager_consume_call_response_registers_streams() -> Result<(), ShellError> {
let mut manager = TestCase::new().plugin("test");
manager.protocol_info = Some(ProtocolInfo::default());
for n in [0, 1] {
fake_plugin_call(&mut manager, n);
}
// Check list streams, external streams
manager.consume(PluginOutput::CallResponse(
0,
PluginCallResponse::PipelineData(PipelineDataHeader::ListStream(ListStreamInfo { id: 0 })),
))?;
manager.consume(PluginOutput::CallResponse(
1,
PluginCallResponse::PipelineData(PipelineDataHeader::ExternalStream(ExternalStreamInfo {
span: Span::test_data(),
stdout: Some(RawStreamInfo {
id: 1,
is_binary: false,
known_size: None,
}),
stderr: Some(RawStreamInfo {
id: 2,
is_binary: false,
known_size: None,
}),
exit_code: Some(ListStreamInfo { id: 3 }),
trim_end_newline: false,
})),
))?;
// ListStream should have one
if let Some(sub) = manager.plugin_call_subscriptions.get(&0) {
assert_eq!(
1, sub.remaining_streams_to_read,
"ListStream remaining_streams_to_read should be 1"
);
} else {
panic!("failed to find subscription for ListStream (0), maybe it was removed");
}
assert_eq!(
Some(&0),
manager.plugin_call_input_streams.get(&0),
"plugin_call_input_streams[0] should be Some(0)"
);
// ExternalStream should have three
if let Some(sub) = manager.plugin_call_subscriptions.get(&1) {
assert_eq!(
3, sub.remaining_streams_to_read,
"ExternalStream remaining_streams_to_read should be 3"
);
} else {
panic!("failed to find subscription for ExternalStream (1), maybe it was removed");
}
for n in [1, 2, 3] {
assert_eq!(
Some(&1),
manager.plugin_call_input_streams.get(&n),
"plugin_call_input_streams[{n}] should be Some(1)"
);
}
Ok(())
}
#[test]
fn manager_consume_engine_call_forwards_to_subscriber_with_pipeline_data() -> Result<(), ShellError>
{
let mut manager = TestCase::new().plugin("test");
manager.protocol_info = Some(ProtocolInfo::default());
let rx = fake_plugin_call(&mut manager, 37);
manager.consume(PluginOutput::EngineCall {
context: 37,
id: 46,
call: EngineCall::EvalClosure {
closure: Spanned {
item: Closure {
block_id: 0,
captures: vec![],
},
span: Span::test_data(),
},
positional: vec![],
input: PipelineDataHeader::ListStream(ListStreamInfo { id: 2 }),
redirect_stdout: false,
redirect_stderr: false,
},
})?;
for i in 0..2 {
manager.consume(PluginOutput::Stream(StreamMessage::Data(
2,
Value::test_int(i).into(),
)))?;
}
manager.consume(PluginOutput::Stream(StreamMessage::End(2)))?;
// Make sure the streams end and we don't deadlock
drop(manager);
let message = rx.try_recv().expect("failed to get plugin call message");
match message {
ReceivedPluginCallMessage::EngineCall(id, call) => {
assert_eq!(46, id, "id");
match call {
EngineCall::EvalClosure { input, .. } => {
// Count the stream messages
assert_eq!(2, input.into_iter().count());
Ok(())
}
_ => panic!("unexpected call: {call:?}"),
}
}
_ => panic!("unexpected response message: {message:?}"),
}
}
#[test]
fn manager_handle_engine_call_after_response_received() -> Result<(), ShellError> {
let test = TestCase::new();
let mut manager = test.plugin("test");
manager.protocol_info = Some(ProtocolInfo::default());
let bogus = Context(Arc::new(PluginExecutionBogusContext));
// Set up a situation identical to what we would find if the response had been read, but there
// was still a stream being processed. We have nowhere to send the engine call in that case,
// so the manager has to create a place to handle it.
manager.plugin_call_subscriptions.insert(
0,
PluginCallSubscription {
sender: None,
context: Some(bogus),
remaining_streams_to_read: 1,
},
);
manager.send_engine_call(0, 0, EngineCall::GetConfig)?;
// Not really much choice but to wait here, as the thread will have been spawned in the
// background; we don't have a way to know if it's executed
let mut waited = 0;
while !test.has_unconsumed_write() {
if waited > 100 {
panic!("nothing written before timeout, expected engine call response");
} else {
std::thread::sleep(Duration::from_millis(1));
waited += 1;
}
}
// The GetConfig call on bogus should result in an error response being written
match test.next_written().expect("nothing written") {
PluginInput::EngineCallResponse(id, resp) => {
assert_eq!(0, id, "id");
match resp {
EngineCallResponse::Error(err) => {
assert!(err.to_string().contains("bogus"), "wrong error: {err}");
}
_ => panic!("unexpected engine call response, expected error: {resp:?}"),
}
}
other => panic!("unexpected message, not engine call response: {other:?}"),
}
// Whatever was used to make this happen should have been held onto, since spawning a thread
// is expensive
let sender = &manager
.plugin_call_subscriptions
.get(&0)
.expect("missing subscription 0")
.sender;
assert!(
sender.is_some(),
"failed to keep spawned engine call handler channel"
);
Ok(())
}
#[test]
fn manager_send_plugin_call_response_removes_context_only_if_no_streams_to_read(
) -> Result<(), ShellError> {
let mut manager = TestCase::new().plugin("test");
for n in [0, 1] {
manager.plugin_call_subscriptions.insert(
n,
PluginCallSubscription {
sender: None,
context: None,
remaining_streams_to_read: n as i32,
},
);
}
for n in [0, 1] {
manager.send_plugin_call_response(n, PluginCallResponse::Signature(vec![]))?;
}
// 0 should not still be present, but 1 should be
assert!(
!manager.plugin_call_subscriptions.contains_key(&0),
"didn't clean up when there weren't remaining streams"
);
assert!(
manager.plugin_call_subscriptions.contains_key(&1),
"clean up even though there were remaining streams"
);
Ok(())
}
#[test]
fn manager_consume_stream_end_removes_context_only_if_last_stream() -> Result<(), ShellError> {
let mut manager = TestCase::new().plugin("test");
manager.protocol_info = Some(ProtocolInfo::default());
for n in [1, 2] {
manager.plugin_call_subscriptions.insert(
n,
PluginCallSubscription {
sender: None,
context: None,
remaining_streams_to_read: n as i32,
},
);
}
// 1 owns [10], 2 owns [21, 22]
manager.plugin_call_input_streams.insert(10, 1);
manager.plugin_call_input_streams.insert(21, 2);
manager.plugin_call_input_streams.insert(22, 2);
// Register the streams so we don't have errors
let streams: Vec<_> = [10, 21, 22]
.into_iter()
.map(|id| {
let interface = manager.get_interface();
manager
.stream_manager
.get_handle()
.read_stream::<Value, _>(id, interface)
})
.collect();
// Ending 10 should cause 1 to be removed
manager.consume(StreamMessage::End(10).into())?;
assert!(
!manager.plugin_call_subscriptions.contains_key(&1),
"contains(1) after End(10)"
);
// Ending 21 should not cause 2 to be removed
manager.consume(StreamMessage::End(21).into())?;
assert!(
manager.plugin_call_subscriptions.contains_key(&2),
"!contains(2) after End(21)"
);
// Ending 22 should cause 2 to be removed
manager.consume(StreamMessage::End(22).into())?;
assert!(
!manager.plugin_call_subscriptions.contains_key(&2),
"contains(2) after End(22)"
);
drop(streams);
Ok(())
}
#[test]
fn manager_prepare_pipeline_data_adds_source_to_values() -> Result<(), ShellError> {
let manager = TestCase::new().plugin("test");
@ -518,7 +800,6 @@ fn interface_write_plugin_call_writes_run_with_value_input() -> Result<(), Shell
named: vec![],
},
input: PipelineData::Value(Value::test_int(-1), None),
config: None,
}),
None,
)?;
@ -557,7 +838,6 @@ fn interface_write_plugin_call_writes_run_with_stream_input() -> Result<(), Shel
named: vec![],
},
input: values.clone().into_pipeline_data(None),
config: None,
}),
None,
)?;
@ -622,7 +902,7 @@ fn interface_receive_plugin_call_receives_response() -> Result<(), ShellError> {
.expect("failed to send on new channel");
drop(tx); // so we don't deadlock on recv()
let response = interface.receive_plugin_call_response(rx)?;
let response = interface.receive_plugin_call_response(rx, &None)?;
assert!(
matches!(response, PluginCallResponse::Signature(_)),
"wrong response: {response:?}"
@ -645,7 +925,7 @@ fn interface_receive_plugin_call_receives_error() -> Result<(), ShellError> {
drop(tx); // so we don't deadlock on recv()
let error = interface
.receive_plugin_call_response(rx)
.receive_plugin_call_response(rx, &None)
.expect_err("did not receive error");
assert!(
matches!(error, ShellError::ExternalNotSupported { .. }),
@ -654,6 +934,49 @@ fn interface_receive_plugin_call_receives_error() -> Result<(), ShellError> {
Ok(())
}
#[test]
fn interface_receive_plugin_call_handles_engine_call() -> Result<(), ShellError> {
let test = TestCase::new();
let interface = test.plugin("test").get_interface();
// Set up a fake channel just for the engine call
let (tx, rx) = mpsc::channel();
tx.send(ReceivedPluginCallMessage::EngineCall(
0,
EngineCall::GetConfig,
))
.expect("failed to send on new channel");
// The context should be a bogus context, which will return an error for GetConfig
let context = Some(Context(Arc::new(PluginExecutionBogusContext)));
// We don't actually send a response, so `receive_plugin_call_response` should actually return
// an error, but it should still do the engine call
drop(tx);
interface
.receive_plugin_call_response(rx, &context)
.expect_err("no error even though there was no response");
// Check for the engine call response output
match test
.next_written()
.expect("no engine call response written")
{
PluginInput::EngineCallResponse(id, resp) => {
assert_eq!(0, id, "id");
match resp {
EngineCallResponse::Error(err) => {
assert!(err.to_string().contains("bogus"), "wrong error: {err}");
}
_ => panic!("unexpected engine call response, maybe bogus is wrong: {resp:?}"),
}
}
other => panic!("unexpected message: {other:?}"),
}
assert!(!test.has_unconsumed_write());
Ok(())
}
/// Fake responses to requests for plugin call messages
fn start_fake_plugin_call_responder(
manager: PluginInterfaceManager,
@ -669,7 +992,11 @@ fn start_fake_plugin_call_responder(
.take(take)
{
for message in f(id) {
sub.sender.send(message).expect("failed to send");
sub.sender
.as_ref()
.expect("sender is None")
.send(message)
.expect("failed to send");
}
}
})
@ -717,7 +1044,6 @@ fn interface_run() -> Result<(), ShellError> {
named: vec![],
},
input: PipelineData::Empty,
config: None,
},
PluginExecutionBogusContext.into(),
)?;

View File

@ -3,20 +3,24 @@ pub use declaration::PluginDeclaration;
use nu_engine::documentation::get_flags_section;
use std::collections::HashMap;
use std::ffi::OsStr;
use std::sync::{Arc, Mutex};
use std::sync::mpsc::TrySendError;
use std::sync::{mpsc, Arc, Mutex};
use crate::plugin::interface::{EngineInterfaceManager, ReceivedPluginCall};
use crate::protocol::{CallInfo, CustomValueOp, LabeledError, PluginInput, PluginOutput};
use crate::protocol::{
CallInfo, CustomValueOp, LabeledError, PluginCustomValue, PluginInput, PluginOutput,
};
use crate::EncodingType;
use std::env;
use std::fmt::Write;
use std::io::{BufReader, Read, Write as WriteTrait};
use std::path::Path;
use std::process::{Child, ChildStdout, Command as CommandSys, Stdio};
use std::{env, thread};
use nu_protocol::{PipelineData, PluginSignature, ShellError, Value};
use nu_protocol::{PipelineData, PluginSignature, ShellError, Spanned, Value};
mod interface;
pub use interface::EngineInterface;
pub(crate) use interface::PluginInterface;
mod context;
@ -184,6 +188,10 @@ pub fn get_signature(
/// If large amounts of data are expected to need to be received or produced, it may be more
/// appropriate to implement [StreamingPlugin] instead.
///
/// The plugin must be able to be safely shared between threads, so that multiple invocations can
/// be run in parallel. If interior mutability is desired, consider synchronization primitives such
/// as [mutexes](std::sync::Mutex) and [channels](std::sync::mpsc).
///
/// # Examples
/// Basic usage:
/// ```
@ -200,9 +208,9 @@ pub fn get_signature(
/// }
///
/// fn run(
/// &mut self,
/// &self,
/// name: &str,
/// config: &Option<Value>,
/// engine: &EngineInterface,
/// call: &EvaluatedCall,
/// input: &Value,
/// ) -> Result<Value, LabeledError> {
@ -211,10 +219,10 @@ pub fn get_signature(
/// }
///
/// # fn main() {
/// # serve_plugin(&mut HelloPlugin{}, MsgPackSerializer)
/// # serve_plugin(&HelloPlugin{}, MsgPackSerializer)
/// # }
/// ```
pub trait Plugin {
pub trait Plugin: Sync {
/// The signature of the plugin
///
/// This method returns the [PluginSignature]s that describe the capabilities
@ -234,12 +242,15 @@ pub trait Plugin {
/// metadata describing how the plugin was invoked and `input` contains the structured
/// data passed to the command implemented by this [Plugin].
///
/// `engine` provides an interface back to the Nushell engine. See [`EngineInterface`] docs for
/// details on what methods are available.
///
/// This variant does not support streaming. Consider implementing [StreamingPlugin] instead
/// if streaming is desired.
fn run(
&mut self,
&self,
name: &str,
config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError>;
@ -270,9 +281,9 @@ pub trait Plugin {
/// }
///
/// fn run(
/// &mut self,
/// &self,
/// name: &str,
/// config: &Option<Value>,
/// engine: &EngineInterface,
/// call: &EvaluatedCall,
/// input: PipelineData,
/// ) -> Result<PipelineData, LabeledError> {
@ -287,10 +298,10 @@ pub trait Plugin {
/// }
///
/// # fn main() {
/// # serve_plugin(&mut LowercasePlugin{}, MsgPackSerializer)
/// # serve_plugin(&LowercasePlugin{}, MsgPackSerializer)
/// # }
/// ```
pub trait StreamingPlugin {
pub trait StreamingPlugin: Sync {
/// The signature of the plugin
///
/// This method returns the [PluginSignature]s that describe the capabilities
@ -315,9 +326,9 @@ pub trait StreamingPlugin {
/// potentially large quantities of bytes. The API is more complex however, and [Plugin] is
/// recommended instead if this is not a concern.
fn run(
&mut self,
&self,
name: &str,
config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
input: PipelineData,
) -> Result<PipelineData, LabeledError>;
@ -331,9 +342,9 @@ impl<T: Plugin> StreamingPlugin for T {
}
fn run(
&mut self,
&self,
name: &str,
config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
input: PipelineData,
) -> Result<PipelineData, LabeledError> {
@ -342,7 +353,7 @@ impl<T: Plugin> StreamingPlugin for T {
let span = input.span().unwrap_or(call.head);
let input_value = input.into_value(span);
// Wrap the output in PipelineData::Value
<Self as Plugin>::run(self, name, config, call, &input_value)
<Self as Plugin>::run(self, name, engine, call, &input_value)
.map(|value| PipelineData::Value(value, None))
}
}
@ -360,14 +371,14 @@ impl<T: Plugin> StreamingPlugin for T {
/// # impl MyPlugin { fn new() -> Self { Self }}
/// # impl Plugin for MyPlugin {
/// # fn signature(&self) -> Vec<PluginSignature> {todo!();}
/// # fn run(&mut self, name: &str, config: &Option<Value>, call: &EvaluatedCall, input: &Value)
/// # fn run(&self, name: &str, engine: &EngineInterface, call: &EvaluatedCall, input: &Value)
/// # -> Result<Value, LabeledError> {todo!();}
/// # }
/// fn main() {
/// serve_plugin(&mut MyPlugin::new(), MsgPackSerializer)
/// serve_plugin(&MyPlugin::new(), MsgPackSerializer)
/// }
/// ```
pub fn serve_plugin(plugin: &mut impl StreamingPlugin, encoder: impl PluginEncoder + 'static) {
pub fn serve_plugin(plugin: &impl StreamingPlugin, encoder: impl PluginEncoder + 'static) {
let mut args = env::args().skip(1);
let number_of_args = args.len();
let first_arg = args.next();
@ -487,61 +498,95 @@ pub fn serve_plugin(plugin: &mut impl StreamingPlugin, encoder: impl PluginEncod
std::process::exit(1);
});
for plugin_call in call_receiver {
match plugin_call {
// Sending the signature back to nushell to create the declaration definition
ReceivedPluginCall::Signature { engine } => {
try_or_report!(engine, engine.write_signature(plugin.signature()));
}
// Run the plugin, handling any input or output streams
ReceivedPluginCall::Run {
engine,
call:
CallInfo {
name,
config,
call,
input,
},
} => {
let result = plugin.run(&name, &config, &call, input);
let write_result = engine
.write_response(result)
.and_then(|writer| writer.write_background());
try_or_report!(engine, write_result);
}
// Do an operation on a custom value
ReceivedPluginCall::CustomValueOp {
engine,
custom_value,
op,
} => {
let local_value = try_or_report!(
engine,
custom_value
.item
.deserialize_to_custom_value(custom_value.span)
);
match op {
CustomValueOp::ToBaseValue => {
let result = local_value
.to_base_value(custom_value.span)
.map(|value| PipelineData::Value(value, None));
let write_result = engine
.write_response(result)
.and_then(|writer| writer.write_background());
try_or_report!(engine, write_result);
// Handle each Run plugin call on a thread
thread::scope(|scope| {
let run = |engine, call_info| {
let CallInfo { name, call, input } = call_info;
let result = plugin.run(&name, &engine, &call, input);
let write_result = engine
.write_response(result)
.and_then(|writer| writer.write());
try_or_report!(engine, write_result);
};
// As an optimization: create one thread that can be reused for Run calls in sequence
let (run_tx, run_rx) = mpsc::sync_channel(0);
thread::Builder::new()
.name("plugin runner (primary)".into())
.spawn_scoped(scope, move || {
for (engine, call) in run_rx {
run(engine, call);
}
})
.unwrap_or_else(|err| {
// If we fail to spawn the runner thread, we should exit
eprintln!("Plugin `{plugin_name}` failed to launch: {err}");
std::process::exit(1);
});
for plugin_call in call_receiver {
match plugin_call {
// Sending the signature back to nushell to create the declaration definition
ReceivedPluginCall::Signature { engine } => {
try_or_report!(engine, engine.write_signature(plugin.signature()));
}
// Run the plugin on a background thread, handling any input or output streams
ReceivedPluginCall::Run { engine, call } => {
// Try to run it on the primary thread
match run_tx.try_send((engine, call)) {
Ok(()) => (),
// If the primary thread isn't ready, spawn a secondary thread to do it
Err(TrySendError::Full((engine, call)))
| Err(TrySendError::Disconnected((engine, call))) => {
let engine_clone = engine.clone();
try_or_report!(
engine_clone,
thread::Builder::new()
.name("plugin runner (secondary)".into())
.spawn_scoped(scope, move || run(engine, call))
.map_err(ShellError::from)
);
}
}
}
// Do an operation on a custom value
ReceivedPluginCall::CustomValueOp {
engine,
custom_value,
op,
} => {
try_or_report!(engine, custom_value_op(&engine, custom_value, op));
}
}
}
}
});
// This will stop the manager
drop(interface);
}
fn print_help(plugin: &mut impl StreamingPlugin, encoder: impl PluginEncoder) {
fn custom_value_op(
engine: &EngineInterface,
custom_value: Spanned<PluginCustomValue>,
op: CustomValueOp,
) -> Result<(), ShellError> {
let local_value = custom_value
.item
.deserialize_to_custom_value(custom_value.span)?;
match op {
CustomValueOp::ToBaseValue => {
let result = local_value
.to_base_value(custom_value.span)
.map(|value| PipelineData::Value(value, None));
engine
.write_response(result)
.and_then(|writer| writer.write_background())?;
Ok(())
}
}
}
fn print_help(plugin: &impl StreamingPlugin, encoder: impl PluginEncoder) {
println!("Nushell Plugin");
println!("Encoder: {}", encoder.name());

View File

@ -9,13 +9,15 @@ mod tests;
pub(crate) mod test_util;
pub use evaluated_call::EvaluatedCall;
use nu_protocol::{PluginSignature, RawStream, ShellError, Span, Spanned, Value};
use nu_protocol::{
engine::Closure, Config, PipelineData, PluginSignature, RawStream, ShellError, Span, Spanned,
Value,
};
pub use plugin_custom_value::PluginCustomValue;
pub(crate) use protocol_info::ProtocolInfo;
use serde::{Deserialize, Serialize};
pub use protocol_info::ProtocolInfo;
#[cfg(test)]
pub(crate) use protocol_info::Protocol;
pub use protocol_info::{Feature, Protocol};
use serde::{Deserialize, Serialize};
/// A sequential identifier for a stream
pub type StreamId = usize;
@ -23,6 +25,9 @@ pub type StreamId = usize;
/// A sequential identifier for a [`PluginCall`]
pub type PluginCallId = usize;
/// A sequential identifier for an [`EngineCall`]
pub type EngineCallId = usize;
/// Information about a plugin command invocation. This includes an [`EvaluatedCall`] as a
/// serializable representation of [`nu_protocol::ast::Call`]. The type parameter determines
/// the input type.
@ -34,8 +39,6 @@ pub struct CallInfo<D> {
pub call: EvaluatedCall,
/// Pipeline input. This is usually [`nu_protocol::PipelineData`] or [`PipelineDataHeader`]
pub input: D,
/// Plugin configuration, if available
pub config: Option<Value>,
}
/// The initial (and perhaps only) part of any [`nu_protocol::PipelineData`] sent over the wire.
@ -57,6 +60,30 @@ pub enum PipelineDataHeader {
ExternalStream(ExternalStreamInfo),
}
impl PipelineDataHeader {
/// Return a list of stream IDs embedded in the header
pub(crate) fn stream_ids(&self) -> Vec<StreamId> {
match self {
PipelineDataHeader::Empty => vec![],
PipelineDataHeader::Value(_) => vec![],
PipelineDataHeader::ListStream(info) => vec![info.id],
PipelineDataHeader::ExternalStream(info) => {
let mut out = vec![];
if let Some(stdout) = &info.stdout {
out.push(stdout.id);
}
if let Some(stderr) = &info.stderr {
out.push(stderr.id);
}
if let Some(exit_code) = &info.exit_code {
out.push(exit_code.id);
}
out
}
}
}
}
/// Additional information about list (value) streams
#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
pub struct ListStreamInfo {
@ -117,6 +144,9 @@ pub enum PluginInput {
/// Don't expect any more plugin calls. Exit after all currently executing plugin calls are
/// finished.
Goodbye,
/// Response to an [`EngineCall`]. The ID should be the same one sent with the engine call this
/// is responding to
EngineCallResponse(EngineCallId, EngineCallResponse<PipelineDataHeader>),
/// Stream control or data message. Untagged to keep them as small as possible.
///
/// For example, `Stream(Ack(0))` is encoded as `{"Ack": 0}`
@ -301,6 +331,15 @@ pub enum PluginOutput {
/// A response to a [`PluginCall`]. The ID should be the same sent with the plugin call this
/// is a response to
CallResponse(PluginCallId, PluginCallResponse<PipelineDataHeader>),
/// Execute an [`EngineCall`]. Engine calls must be executed within the `context` of a plugin
/// call, and the `id` should not have been used before
EngineCall {
/// The plugin call (by ID) to execute in the context of
context: PluginCallId,
/// A new identifier for this engine call. The response will reference this ID
id: EngineCallId,
call: EngineCall<PipelineDataHeader>,
},
/// Stream control or data message. Untagged to keep them as small as possible.
///
/// For example, `Stream(Ack(0))` is encoded as `{"Ack": 0}`
@ -324,3 +363,61 @@ impl From<StreamMessage> for PluginOutput {
PluginOutput::Stream(stream_msg)
}
}
/// A remote call back to the engine during the plugin's execution.
///
/// The type parameter determines the input type, for calls that take pipeline data.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub enum EngineCall<D> {
/// Get the full engine configuration
GetConfig,
/// Get the plugin-specific configuration (`$env.config.plugins.NAME`)
GetPluginConfig,
/// Evaluate a closure with stream input/output
EvalClosure {
/// The closure to call.
///
/// This may come from a [`Value::Closure`] passed in as an argument to the plugin.
closure: Spanned<Closure>,
/// Positional arguments to add to the closure call
positional: Vec<Value>,
/// Input to the closure
input: D,
/// Whether to redirect stdout from external commands
redirect_stdout: bool,
/// Whether to redirect stderr from external commands
redirect_stderr: bool,
},
}
impl<D> EngineCall<D> {
/// Get the name of the engine call so it can be embedded in things like error messages
pub fn name(&self) -> &'static str {
match self {
EngineCall::GetConfig => "GetConfig",
EngineCall::GetPluginConfig => "GetPluginConfig",
EngineCall::EvalClosure { .. } => "EvalClosure",
}
}
}
/// The response to an [EngineCall]. The type parameter determines the output type for pipeline
/// data.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub enum EngineCallResponse<D> {
Error(ShellError),
PipelineData(D),
Config(Box<Config>),
}
impl EngineCallResponse<PipelineData> {
/// Build an [`EngineCallResponse::PipelineData`] from a [`Value`]
pub(crate) fn value(value: Value) -> EngineCallResponse<PipelineData> {
EngineCallResponse::PipelineData(PipelineData::Value(value, None))
}
/// An [`EngineCallResponse::PipelineData`] with [`PipelineData::Empty`]
pub(crate) const fn empty() -> EngineCallResponse<PipelineData> {
EngineCallResponse::PipelineData(PipelineData::Empty)
}
}

View File

@ -146,6 +146,11 @@ impl PluginCustomValue {
Self::add_source(list_value, source);
}
}
Value::Closure { ref mut val, .. } => {
for (_, captured_value) in val.captures.iter_mut() {
Self::add_source(captured_value, source);
}
}
// All of these don't contain other values
Value::Bool { .. }
| Value::Int { .. }
@ -156,7 +161,6 @@ impl PluginCustomValue {
| Value::String { .. }
| Value::Glob { .. }
| Value::Block { .. }
| Value::Closure { .. }
| Value::Nothing { .. }
| Value::Error { .. }
| Value::Binary { .. }
@ -214,6 +218,10 @@ impl PluginCustomValue {
Value::List { ref mut vals, .. } => vals
.iter_mut()
.try_for_each(|list_value| Self::verify_source(list_value, source)),
Value::Closure { ref mut val, .. } => val
.captures
.iter_mut()
.try_for_each(|(_, captured_value)| Self::verify_source(captured_value, source)),
// All of these don't contain other values
Value::Bool { .. }
| Value::Int { .. }
@ -224,7 +232,6 @@ impl PluginCustomValue {
| Value::String { .. }
| Value::Glob { .. }
| Value::Block { .. }
| Value::Closure { .. }
| Value::Nothing { .. }
| Value::Error { .. }
| Value::Binary { .. }
@ -266,6 +273,11 @@ impl PluginCustomValue {
Value::List { ref mut vals, .. } => vals
.iter_mut()
.try_for_each(Self::serialize_custom_values_in),
Value::Closure { ref mut val, .. } => val
.captures
.iter_mut()
.map(|(_, captured_value)| captured_value)
.try_for_each(Self::serialize_custom_values_in),
// All of these don't contain other values
Value::Bool { .. }
| Value::Int { .. }
@ -276,7 +288,6 @@ impl PluginCustomValue {
| Value::String { .. }
| Value::Glob { .. }
| Value::Block { .. }
| Value::Closure { .. }
| Value::Nothing { .. }
| Value::Error { .. }
| Value::Binary { .. }
@ -316,6 +327,11 @@ impl PluginCustomValue {
Value::List { ref mut vals, .. } => vals
.iter_mut()
.try_for_each(Self::deserialize_custom_values_in),
Value::Closure { ref mut val, .. } => val
.captures
.iter_mut()
.map(|(_, captured_value)| captured_value)
.try_for_each(Self::deserialize_custom_values_in),
// All of these don't contain other values
Value::Bool { .. }
| Value::Int { .. }
@ -326,7 +342,6 @@ impl PluginCustomValue {
| Value::String { .. }
| Value::Glob { .. }
| Value::Block { .. }
| Value::Closure { .. }
| Value::Nothing { .. }
| Value::Error { .. }
| Value::Binary { .. }

View File

@ -1,4 +1,6 @@
use nu_protocol::{ast::RangeInclusion, record, CustomValue, Range, ShellError, Span, Value};
use nu_protocol::{
ast::RangeInclusion, engine::Closure, record, CustomValue, Range, ShellError, Span, Value,
};
use crate::{
plugin::PluginIdentity,
@ -180,6 +182,50 @@ fn add_source_nested_list() -> Result<(), ShellError> {
})
}
fn check_closure_custom_values(
val: &Value,
indices: impl IntoIterator<Item = usize>,
mut f: impl FnMut(usize, &dyn CustomValue) -> Result<(), ShellError>,
) -> Result<(), ShellError> {
let closure = val.as_closure()?;
for index in indices {
let val = closure
.captures
.get(index)
.unwrap_or_else(|| panic!("[{index}] not present in closure"));
let custom_value = val
.1
.as_custom_value()
.unwrap_or_else(|_| panic!("[{index}] not custom value"));
f(index, custom_value)?;
}
Ok(())
}
#[test]
fn add_source_nested_closure() -> Result<(), ShellError> {
let orig_custom_val = Value::test_custom_value(Box::new(test_plugin_custom_value()));
let mut val = Value::test_closure(Closure {
block_id: 0,
captures: vec![(0, orig_custom_val.clone()), (1, orig_custom_val.clone())],
});
let source = PluginIdentity::new_fake("foo");
PluginCustomValue::add_source(&mut val, &source);
check_closure_custom_values(&val, 0..=1, |index, custom_value| {
let plugin_custom_value: &PluginCustomValue = custom_value
.as_any()
.downcast_ref()
.unwrap_or_else(|| panic!("[{index}] not PluginCustomValue"));
assert_eq!(
Some(&source),
plugin_custom_value.source.as_ref(),
"[{index}] source not set correctly"
);
Ok(())
})
}
#[test]
fn verify_source_error_message() -> Result<(), ShellError> {
let span = Span::new(5, 7);
@ -322,6 +368,40 @@ fn verify_source_nested_list() -> Result<(), ShellError> {
Ok(())
}
#[test]
fn verify_source_nested_closure() -> Result<(), ShellError> {
let native_val = Value::test_custom_value(Box::new(TestCustomValue(32)));
let source = PluginIdentity::new_fake("test");
for (name, mut val) in [
(
"first capture",
Value::test_closure(Closure {
block_id: 0,
captures: vec![(0, native_val.clone()), (1, Value::test_nothing())],
}),
),
(
"second capture",
Value::test_closure(Closure {
block_id: 0,
captures: vec![(0, Value::test_nothing()), (1, native_val.clone())],
}),
),
] {
PluginCustomValue::verify_source(&mut val, &source)
.expect_err(&format!("error not generated on {name}"));
}
let mut ok_closure = Value::test_closure(Closure {
block_id: 0,
captures: vec![(0, Value::test_nothing())],
});
PluginCustomValue::verify_source(&mut ok_closure, &source)
.expect("ok_closure should not generate error");
Ok(())
}
#[test]
fn serialize_in_root() -> Result<(), ShellError> {
let span = Span::new(4, 10);
@ -406,6 +486,28 @@ fn serialize_in_list() -> Result<(), ShellError> {
})
}
#[test]
fn serialize_in_closure() -> Result<(), ShellError> {
let orig_custom_val = Value::test_custom_value(Box::new(TestCustomValue(24)));
let mut val = Value::test_closure(Closure {
block_id: 0,
captures: vec![(0, orig_custom_val.clone()), (1, orig_custom_val.clone())],
});
PluginCustomValue::serialize_custom_values_in(&mut val)?;
check_closure_custom_values(&val, 0..=1, |index, custom_value| {
let plugin_custom_value: &PluginCustomValue = custom_value
.as_any()
.downcast_ref()
.unwrap_or_else(|| panic!("[{index}] not PluginCustomValue"));
assert_eq!(
"TestCustomValue", plugin_custom_value.name,
"[{index}] name not set correctly"
);
Ok(())
})
}
#[test]
fn deserialize_in_root() -> Result<(), ShellError> {
let span = Span::new(4, 10);
@ -490,3 +592,26 @@ fn deserialize_in_list() -> Result<(), ShellError> {
Ok(())
})
}
#[test]
fn deserialize_in_closure() -> Result<(), ShellError> {
let orig_custom_val = Value::test_custom_value(Box::new(test_plugin_custom_value()));
let mut val = Value::test_closure(Closure {
block_id: 0,
captures: vec![(0, orig_custom_val.clone()), (1, orig_custom_val.clone())],
});
PluginCustomValue::deserialize_custom_values_in(&mut val)?;
check_closure_custom_values(&val, 0..=1, |index, custom_value| {
let test_custom_value: &TestCustomValue = custom_value
.as_any()
.downcast_ref()
.unwrap_or_else(|| panic!("[{index}] not TestCustomValue"));
assert_eq!(
expected_test_custom_value(),
*test_custom_value,
"[{index}] name not deserialized correctly"
);
Ok(())
})
}

View File

@ -125,7 +125,6 @@ macro_rules! generate_tests {
name: name.clone(),
call: call.clone(),
input: PipelineDataHeader::Value(input.clone()),
config: None,
});
let plugin_input = PluginInput::Call(1, plugin_call);

View File

@ -855,6 +855,15 @@ impl EngineState {
.expect("internal error: missing block")
}
/// Optionally get a block by id, if it exists
///
/// Prefer to use [`.get_block()`] in most cases - `BlockId`s that don't exist are normally a
/// compiler error. This only exists to stop plugins from crashing the engine if they send us
/// something invalid.
pub fn try_get_block(&self, block_id: BlockId) -> Option<&Block> {
self.blocks.get(block_id)
}
pub fn get_module(&self, module_id: ModuleId) -> &Module {
self.modules
.get(module_id)

View File

@ -2,7 +2,7 @@ mod cool_custom_value;
mod second_custom_value;
use cool_custom_value::CoolCustomValue;
use nu_plugin::{serve_plugin, MsgPackSerializer, Plugin};
use nu_plugin::{serve_plugin, EngineInterface, MsgPackSerializer, Plugin};
use nu_plugin::{EvaluatedCall, LabeledError};
use nu_protocol::{Category, PluginSignature, ShellError, SyntaxShape, Value};
use second_custom_value::SecondCustomValue;
@ -17,6 +17,11 @@ impl Plugin for CustomValuePlugin {
.category(Category::Experimental),
PluginSignature::build("custom-value generate2")
.usage("PluginSignature for a plugin that generates a different custom value")
.optional(
"closure",
SyntaxShape::Closure(Some(vec![SyntaxShape::Any])),
"An optional closure to pass the custom value to",
)
.category(Category::Experimental),
PluginSignature::build("custom-value update")
.usage("PluginSignature for a plugin that updates a custom value")
@ -33,15 +38,15 @@ impl Plugin for CustomValuePlugin {
}
fn run(
&mut self,
&self,
name: &str,
_config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError> {
match name {
"custom-value generate" => self.generate(call, input),
"custom-value generate2" => self.generate2(call, input),
"custom-value generate2" => self.generate2(engine, call),
"custom-value update" => self.update(call, input),
"custom-value update-arg" => self.update(call, &call.req(0)?),
_ => Err(LabeledError {
@ -54,15 +59,30 @@ impl Plugin for CustomValuePlugin {
}
impl CustomValuePlugin {
fn generate(&mut self, call: &EvaluatedCall, _input: &Value) -> Result<Value, LabeledError> {
fn generate(&self, call: &EvaluatedCall, _input: &Value) -> Result<Value, LabeledError> {
Ok(CoolCustomValue::new("abc").into_value(call.head))
}
fn generate2(&mut self, call: &EvaluatedCall, _input: &Value) -> Result<Value, LabeledError> {
Ok(SecondCustomValue::new("xyz").into_value(call.head))
fn generate2(
&self,
engine: &EngineInterface,
call: &EvaluatedCall,
) -> Result<Value, LabeledError> {
let second_custom_value = SecondCustomValue::new("xyz").into_value(call.head);
// If we were passed a closure, execute that instead
if let Some(closure) = call.opt(0)? {
let result = engine.eval_closure(
&closure,
vec![second_custom_value.clone()],
Some(second_custom_value),
)?;
Ok(result)
} else {
Ok(second_custom_value)
}
}
fn update(&mut self, call: &EvaluatedCall, input: &Value) -> Result<Value, LabeledError> {
fn update(&self, call: &EvaluatedCall, input: &Value) -> Result<Value, LabeledError> {
if let Ok(mut value) = CoolCustomValue::try_from_value(input) {
value.cool += "xyz";
return Ok(value.into_value(call.head));
@ -84,5 +104,5 @@ impl CustomValuePlugin {
}
fn main() {
serve_plugin(&mut CustomValuePlugin, MsgPackSerializer {})
serve_plugin(&CustomValuePlugin, MsgPackSerializer {})
}

View File

@ -1,13 +1,14 @@
use nu_plugin::{EvaluatedCall, LabeledError};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError};
use nu_protocol::{record, Value};
pub struct Example;
impl Example {
pub fn config(
&self,
config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
) -> Result<Value, LabeledError> {
let config = engine.get_plugin_config()?;
match config {
Some(config) => Ok(config.clone()),
None => Err(LabeledError {

View File

@ -6,7 +6,7 @@ fn main() {
// used to encode and decode the messages. The available options are
// MsgPackSerializer and JsonSerializer. Both are defined in the serializer
// folder in nu-plugin.
serve_plugin(&mut Example {}, MsgPackSerializer {})
serve_plugin(&Example {}, MsgPackSerializer {})
// Note
// When creating plugins in other languages one needs to consider how a plugin

View File

@ -1,5 +1,5 @@
use crate::Example;
use nu_plugin::{EvaluatedCall, LabeledError, Plugin};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError, Plugin};
use nu_protocol::{Category, PluginExample, PluginSignature, SyntaxShape, Type, Value};
impl Plugin for Example {
@ -52,9 +52,9 @@ impl Plugin for Example {
}
fn run(
&mut self,
&self,
name: &str,
config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError> {
@ -63,7 +63,7 @@ impl Plugin for Example {
"nu-example-1" => self.test1(call, input),
"nu-example-2" => self.test2(call, input),
"nu-example-3" => self.test3(call, input),
"nu-example-config" => self.config(config, call),
"nu-example-config" => self.config(engine, call),
_ => Err(LabeledError {
label: "Plugin call with wrong name signature".into(),
msg: "the signature used to call the plugin does not match any name in the plugin signature vector".into(),

View File

@ -1,7 +1,7 @@
mod from;
use from::{eml, ics, ini, vcf};
use nu_plugin::{EvaluatedCall, LabeledError, Plugin};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError, Plugin};
use nu_protocol::{Category, PluginSignature, SyntaxShape, Type, Value};
pub struct FromCmds;
@ -39,9 +39,9 @@ impl Plugin for FromCmds {
}
fn run(
&mut self,
&self,
name: &str,
_config: &Option<Value>,
_engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError> {

View File

@ -2,5 +2,5 @@ use nu_plugin::{serve_plugin, MsgPackSerializer};
use nu_plugin_formats::FromCmds;
fn main() {
serve_plugin(&mut FromCmds, MsgPackSerializer {})
serve_plugin(&FromCmds, MsgPackSerializer {})
}

View File

@ -2,5 +2,5 @@ use nu_plugin::{serve_plugin, MsgPackSerializer};
use nu_plugin_gstat::GStat;
fn main() {
serve_plugin(&mut GStat::new(), MsgPackSerializer {})
serve_plugin(&GStat::new(), MsgPackSerializer {})
}

View File

@ -1,5 +1,5 @@
use crate::GStat;
use nu_plugin::{EvaluatedCall, LabeledError, Plugin};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError, Plugin};
use nu_protocol::{Category, PluginSignature, Spanned, SyntaxShape, Value};
impl Plugin for GStat {
@ -11,9 +11,9 @@ impl Plugin for GStat {
}
fn run(
&mut self,
&self,
name: &str,
_config: &Option<Value>,
_engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError> {

View File

@ -2,20 +2,20 @@ use nu_plugin::LabeledError;
use nu_protocol::{ast::CellPath, Span, Value};
use semver::{BuildMetadata, Prerelease, Version};
#[derive(Debug, Eq, PartialEq)]
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum Action {
SemVerAction(SemVerAction),
Default,
}
#[derive(Debug, Eq, PartialEq)]
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum SemVerAction {
Major,
Minor,
Patch,
}
#[derive(Default)]
#[derive(Default, Clone)]
pub struct Inc {
pub error: Option<String>,
pub cell_path: Option<CellPath>,

View File

@ -2,5 +2,5 @@ use nu_plugin::{serve_plugin, JsonSerializer};
use nu_plugin_inc::Inc;
fn main() {
serve_plugin(&mut Inc::new(), JsonSerializer {})
serve_plugin(&Inc::new(), JsonSerializer {})
}

View File

@ -1,6 +1,6 @@
use crate::inc::SemVerAction;
use crate::Inc;
use nu_plugin::{EvaluatedCall, LabeledError, Plugin};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError, Plugin};
use nu_protocol::{ast::CellPath, PluginSignature, SyntaxShape, Value};
impl Plugin for Inc {
@ -26,9 +26,9 @@ impl Plugin for Inc {
}
fn run(
&mut self,
&self,
name: &str,
_config: &Option<Value>,
_engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError> {
@ -36,20 +36,22 @@ impl Plugin for Inc {
return Ok(Value::nothing(call.head));
}
let mut inc = self.clone();
let cell_path: Option<CellPath> = call.opt(0)?;
self.cell_path = cell_path;
inc.cell_path = cell_path;
if call.has_flag("major")? {
self.for_semver(SemVerAction::Major);
inc.for_semver(SemVerAction::Major);
}
if call.has_flag("minor")? {
self.for_semver(SemVerAction::Minor);
inc.for_semver(SemVerAction::Minor);
}
if call.has_flag("patch")? {
self.for_semver(SemVerAction::Patch);
inc.for_semver(SemVerAction::Patch);
}
self.inc(call.head, input)
inc.inc(call.head, input)
}
}

View File

@ -2,5 +2,5 @@ use nu_plugin::{serve_plugin, JsonSerializer};
use nu_plugin_query::Query;
fn main() {
serve_plugin(&mut Query {}, JsonSerializer {})
serve_plugin(&Query {}, JsonSerializer {})
}

View File

@ -1,5 +1,5 @@
use crate::Query;
use nu_plugin::{EvaluatedCall, LabeledError, Plugin};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError, Plugin};
use nu_protocol::{Category, PluginExample, PluginSignature, Spanned, SyntaxShape, Value};
impl Plugin for Query {
@ -46,9 +46,9 @@ impl Plugin for Query {
}
fn run(
&mut self,
&self,
name: &str,
_config: &Option<Value>,
_engine: &EngineInterface,
call: &EvaluatedCall,
input: &Value,
) -> Result<Value, LabeledError> {

View File

@ -46,3 +46,18 @@ strings on input will be concatenated into an external stream (raw input) on std
Hello
worldhowareyou
## `stream_example for-each`
This command demonstrates executing closures on values in streams. Each value received on the input
will be printed to the plugin's stderr. This works even with external commands.
> ```nushell
> ls | get name | stream_example for-each { |f| ^file $f }
> ```
CODE_OF_CONDUCT.md: ASCII text
CONTRIBUTING.md: ASCII text, with very long lines (303)
...

View File

@ -1,5 +1,5 @@
use nu_plugin::{EvaluatedCall, LabeledError};
use nu_protocol::{ListStream, PipelineData, RawStream, Value};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError};
use nu_protocol::{IntoInterruptiblePipelineData, ListStream, PipelineData, RawStream, Value};
pub struct Example;
@ -64,4 +64,52 @@ impl Example {
trim_end_newline: false,
})
}
pub fn for_each(
&self,
engine: &EngineInterface,
call: &EvaluatedCall,
input: PipelineData,
) -> Result<PipelineData, LabeledError> {
let closure = call.req(0)?;
let config = engine.get_config()?;
for value in input {
let result = engine.eval_closure(&closure, vec![value.clone()], Some(value))?;
eprintln!("{}", result.to_expanded_string(", ", &config));
}
Ok(PipelineData::Empty)
}
pub fn generate(
&self,
engine: &EngineInterface,
call: &EvaluatedCall,
) -> Result<PipelineData, LabeledError> {
let engine = engine.clone();
let call = call.clone();
let initial: Value = call.req(0)?;
let closure = call.req(1)?;
let mut next = (!initial.is_nothing()).then_some(initial);
Ok(std::iter::from_fn(move || {
next.take()
.and_then(|value| {
engine
.eval_closure(&closure, vec![value.clone()], Some(value))
.and_then(|record| {
if record.is_nothing() {
Ok(None)
} else {
let record = record.as_record()?;
next = record.get("next").cloned();
Ok(record.get("out").cloned())
}
})
.transpose()
})
.map(|result| result.unwrap_or_else(|err| Value::error(err, call.head)))
})
.into_pipeline_data(None))
}
}

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@ -6,7 +6,7 @@ fn main() {
// used to encode and decode the messages. The available options are
// MsgPackSerializer and JsonSerializer. Both are defined in the serializer
// folder in nu-plugin.
serve_plugin(&mut Example {}, MsgPackSerializer {})
serve_plugin(&Example {}, MsgPackSerializer {})
// Note
// When creating plugins in other languages one needs to consider how a plugin

View File

@ -1,5 +1,5 @@
use crate::Example;
use nu_plugin::{EvaluatedCall, LabeledError, StreamingPlugin};
use nu_plugin::{EngineInterface, EvaluatedCall, LabeledError, StreamingPlugin};
use nu_protocol::{
Category, PipelineData, PluginExample, PluginSignature, Span, SyntaxShape, Type, Value,
};
@ -57,13 +57,50 @@ impl StreamingPlugin for Example {
result: Some(Value::string("ab", span)),
}])
.category(Category::Experimental),
PluginSignature::build("stream_example for-each")
.usage("Example execution of a closure with a stream")
.extra_usage("Prints each value the closure returns to stderr")
.input_output_type(Type::ListStream, Type::Nothing)
.required(
"closure",
SyntaxShape::Closure(Some(vec![SyntaxShape::Any])),
"The closure to run for each input value",
)
.plugin_examples(vec![PluginExample {
example: "ls | get name | stream_example for-each { |f| ^file $f }".into(),
description: "example with an external command".into(),
result: None,
}])
.category(Category::Experimental),
PluginSignature::build("stream_example generate")
.usage("Example execution of a closure to produce a stream")
.extra_usage("See the builtin `generate` command")
.input_output_type(Type::Nothing, Type::ListStream)
.required(
"initial",
SyntaxShape::Any,
"The initial value to pass to the closure"
)
.required(
"closure",
SyntaxShape::Closure(Some(vec![SyntaxShape::Any])),
"The closure to run to generate values",
)
.plugin_examples(vec![PluginExample {
example: "stream_example generate 0 { |i| if $i <= 10 { {out: $i, next: ($i + 2)} } }".into(),
description: "Generate a sequence of numbers".into(),
result: Some(Value::test_list(
[0, 2, 4, 6, 8, 10].into_iter().map(Value::test_int).collect(),
)),
}])
.category(Category::Experimental),
]
}
fn run(
&mut self,
&self,
name: &str,
_config: &Option<Value>,
engine: &EngineInterface,
call: &EvaluatedCall,
input: PipelineData,
) -> Result<PipelineData, LabeledError> {
@ -76,6 +113,8 @@ impl StreamingPlugin for Example {
"stream_example seq" => self.seq(call, input),
"stream_example sum" => self.sum(call, input),
"stream_example collect-external" => self.collect_external(call, input),
"stream_example for-each" => self.for_each(engine, call, input),
"stream_example generate" => self.generate(engine, call),
_ => Err(LabeledError {
label: "Plugin call with wrong name signature".into(),
msg: "the signature used to call the plugin does not match any name in the plugin signature vector".into(),

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@ -54,6 +54,20 @@ fn can_generate_and_updated_multiple_types_of_custom_values() {
);
}
#[test]
fn can_generate_custom_value_and_pass_through_closure() {
let actual = nu_with_plugins!(
cwd: "tests",
plugin: ("nu_plugin_custom_values"),
"custom-value generate2 { custom-value update }"
);
assert_eq!(
actual.out,
"I used to be a DIFFERENT custom value! (xyzabc)"
);
}
#[test]
fn can_get_describe_plugin_custom_values() {
let actual = nu_with_plugins!(

View File

@ -164,3 +164,25 @@ fn collect_external_big_stream() {
assert_eq!(actual.out, "10000");
}
#[test]
fn for_each_prints_on_stderr() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_stream_example"),
"[a b c] | stream_example for-each { $in }"
);
assert_eq!(actual.err, "a\nb\nc\n");
}
#[test]
fn generate_sequence() {
let actual = nu_with_plugins!(
cwd: "tests/fixtures/formats",
plugin: ("nu_plugin_stream_example"),
"stream_example generate 0 { |i| if $i <= 10 { {out: $i, next: ($i + 2)} } } | to json --raw"
);
assert_eq!(actual.out, "[0,2,4,6,8,10]");
}