nushell/crates/nu-cli/src/commands/to_json.rs
2020-06-14 07:13:36 +12:00

276 lines
11 KiB
Rust

use crate::commands::WholeStreamCommand;
use crate::prelude::*;
use nu_errors::{CoerceInto, ShellError};
use nu_protocol::{
Primitive, ReturnSuccess, Signature, SyntaxShape, UnspannedPathMember, UntaggedValue, Value,
};
use serde::Serialize;
use serde_json::json;
pub struct ToJSON;
#[derive(Deserialize)]
pub struct ToJSONArgs {
pretty: Option<Value>,
}
#[async_trait]
impl WholeStreamCommand for ToJSON {
fn name(&self) -> &str {
"to json"
}
fn signature(&self) -> Signature {
Signature::build("to json").named(
"pretty",
SyntaxShape::Int,
"Formats the JSON text with the provided indentation setting",
Some('p'),
)
}
fn usage(&self) -> &str {
"Converts table data into JSON text."
}
async fn run(
&self,
args: CommandArgs,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
to_json(args, registry).await
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description:
"Outputs an unformatted JSON string representing the contents of this table",
example: "echo [1 2 3] | to json",
result: Some(vec![Value::from("[1,2,3]")]),
},
Example {
description:
"Outputs a formatted JSON string representing the contents of this table with an indentation setting of 2 spaces",
example: "echo [1 2 3] | to json --pretty 2",
result: Some(vec![Value::from("[\n 1,\n 2,\n 3\n]")]),
},
]
}
}
pub fn value_to_json_value(v: &Value) -> Result<serde_json::Value, ShellError> {
Ok(match &v.value {
UntaggedValue::Primitive(Primitive::Boolean(b)) => serde_json::Value::Bool(*b),
UntaggedValue::Primitive(Primitive::Bytes(b)) => serde_json::Value::Number(
serde_json::Number::from(b.to_u64().expect("What about really big numbers")),
),
UntaggedValue::Primitive(Primitive::Duration(secs)) => {
serde_json::Value::Number(serde_json::Number::from(*secs))
}
UntaggedValue::Primitive(Primitive::Date(d)) => serde_json::Value::String(d.to_string()),
UntaggedValue::Primitive(Primitive::EndOfStream) => serde_json::Value::Null,
UntaggedValue::Primitive(Primitive::BeginningOfStream) => serde_json::Value::Null,
UntaggedValue::Primitive(Primitive::Decimal(f)) => {
if let Some(f) = f.to_f64() {
if let Some(num) = serde_json::Number::from_f64(
f.to_f64().expect("TODO: What about really big decimals?"),
) {
serde_json::Value::Number(num)
} else {
return Err(ShellError::labeled_error(
"Could not convert value to decimal number",
"could not convert to decimal",
&v.tag,
));
}
} else {
return Err(ShellError::labeled_error(
"Could not convert value to decimal number",
"could not convert to decimal",
&v.tag,
));
}
}
UntaggedValue::Primitive(Primitive::Int(i)) => {
serde_json::Value::Number(serde_json::Number::from(CoerceInto::<i64>::coerce_into(
i.tagged(&v.tag),
"converting to JSON number",
)?))
}
UntaggedValue::Primitive(Primitive::Nothing) => serde_json::Value::Null,
UntaggedValue::Primitive(Primitive::Pattern(s)) => serde_json::Value::String(s.clone()),
UntaggedValue::Primitive(Primitive::String(s)) => serde_json::Value::String(s.clone()),
UntaggedValue::Primitive(Primitive::Line(s)) => serde_json::Value::String(s.clone()),
UntaggedValue::Primitive(Primitive::ColumnPath(path)) => serde_json::Value::Array(
path.iter()
.map(|x| match &x.unspanned {
UnspannedPathMember::String(string) => {
Ok(serde_json::Value::String(string.clone()))
}
UnspannedPathMember::Int(int) => Ok(serde_json::Value::Number(
serde_json::Number::from(CoerceInto::<i64>::coerce_into(
int.tagged(&v.tag),
"converting to JSON number",
)?),
)),
})
.collect::<Result<Vec<serde_json::Value>, ShellError>>()?,
),
UntaggedValue::Primitive(Primitive::Path(s)) => {
serde_json::Value::String(s.display().to_string())
}
UntaggedValue::Table(l) => serde_json::Value::Array(json_list(l)?),
UntaggedValue::Error(e) => return Err(e.clone()),
UntaggedValue::Block(_) | UntaggedValue::Primitive(Primitive::Range(_)) => {
serde_json::Value::Null
}
UntaggedValue::Primitive(Primitive::Binary(b)) => serde_json::Value::Array(
b.iter()
.map(|x| {
serde_json::Number::from_f64(*x as f64).ok_or_else(|| {
ShellError::labeled_error(
"Can not convert number from floating point",
"can not convert to number",
&v.tag,
)
})
})
.collect::<Result<Vec<serde_json::Number>, ShellError>>()?
.into_iter()
.map(serde_json::Value::Number)
.collect(),
),
UntaggedValue::Row(o) => {
let mut m = serde_json::Map::new();
for (k, v) in o.entries.iter() {
m.insert(k.clone(), value_to_json_value(v)?);
}
serde_json::Value::Object(m)
}
})
}
fn json_list(input: &[Value]) -> Result<Vec<serde_json::Value>, ShellError> {
let mut out = vec![];
for value in input {
out.push(value_to_json_value(value)?);
}
Ok(out)
}
async fn to_json(
args: CommandArgs,
registry: &CommandRegistry,
) -> Result<OutputStream, ShellError> {
let registry = registry.clone();
let name_tag = args.call_info.name_tag.clone();
let (ToJSONArgs { pretty }, input) = args.process(&registry).await?;
let name_span = name_tag.span;
let input: Vec<Value> = input.collect().await;
let to_process_input = match input.len() {
x if x > 1 => {
let tag = input[0].tag.clone();
vec![Value {
value: UntaggedValue::Table(input),
tag,
}]
}
1 => input,
_ => vec![],
};
Ok(futures::stream::iter(to_process_input.into_iter().map(
move |value| match value_to_json_value(&value) {
Ok(json_value) => {
let value_span = value.tag.span;
match serde_json::to_string(&json_value) {
Ok(mut serde_json_string) => {
if let Some(pretty_value) = &pretty {
let mut pretty_format_failed = true;
if let Ok(pretty_u64) = pretty_value.as_u64() {
if let Ok(serde_json_value) =
serde_json::from_str::<serde_json::Value>(
serde_json_string.as_str(),
)
{
let indentation_string = std::iter::repeat(" ")
.take(pretty_u64 as usize)
.collect::<String>();
let serde_formatter =
serde_json::ser::PrettyFormatter::with_indent(
indentation_string.as_bytes(),
);
let serde_buffer = Vec::new();
let mut serde_serializer =
serde_json::Serializer::with_formatter(
serde_buffer,
serde_formatter,
);
let serde_json_object = json!(serde_json_value);
if let Ok(()) =
serde_json_object.serialize(&mut serde_serializer)
{
if let Ok(ser_json_string) =
String::from_utf8(serde_serializer.into_inner())
{
pretty_format_failed = false;
serde_json_string = ser_json_string
}
}
}
}
if pretty_format_failed {
return Err(ShellError::labeled_error(
"Pretty formatting failed",
"failed",
pretty_value.tag(),
));
}
}
ReturnSuccess::value(
UntaggedValue::Primitive(Primitive::String(serde_json_string))
.into_value(&name_tag),
)
}
_ => Err(ShellError::labeled_error_with_secondary(
"Expected a table with JSON-compatible structure.tag() from pipeline",
"requires JSON-compatible input",
name_span,
"originates from here".to_string(),
value_span,
)),
}
}
_ => Err(ShellError::labeled_error(
"Expected a table with JSON-compatible structure from pipeline",
"requires JSON-compatible input",
&name_tag,
)),
},
))
.to_output_stream())
}
#[cfg(test)]
mod tests {
use super::ToJSON;
#[test]
fn examples_work_as_expected() {
use crate::examples::test as test_examples;
test_examples(ToJSON {})
}
}