Add wasm support (#2199)

* Working towards a PoC for wasm

* Move bson and sqlite to plugins

* proof of concept now working

* tests are green

* Add CI test for --no-default-features

* Fix some tests

* Fix clippy and windows build

* More fixes

* Fix the windows build

* Fix the windows test

crates/nu_plugin_from_sqlite/src/from_sqlite.rs

@@ -0,0 +1,117 @@
+use nu_errors::ShellError;
+use nu_protocol::{Primitive, ReturnSuccess, ReturnValue, TaggedDictBuilder, UntaggedValue, Value};
+use nu_source::Tag;
+use rusqlite::{types::ValueRef, Connection, Row, NO_PARAMS};
+use std::io::Write;
+use std::path::Path;
+
+#[derive(Default)]
+pub struct FromSqlite {
+    pub state: Vec<u8>,
+    pub name_tag: Tag,
+}
+
+impl FromSqlite {
+    pub fn new() -> FromSqlite {
+        FromSqlite {
+            state: vec![],
+            name_tag: Tag::unknown(),
+        }
+    }
+}
+
+pub fn convert_sqlite_file_to_nu_value(
+    path: &Path,
+    tag: impl Into<Tag> + Clone,
+) -> Result<Value, rusqlite::Error> {
+    let conn = Connection::open(path)?;
+
+    let mut meta_out = Vec::new();
+    let mut meta_stmt = conn.prepare("select name from sqlite_master where type='table'")?;
+    let mut meta_rows = meta_stmt.query(NO_PARAMS)?;
+
+    while let Some(meta_row) = meta_rows.next()? {
+        let table_name: String = meta_row.get(0)?;
+        let mut meta_dict = TaggedDictBuilder::new(tag.clone());
+        let mut out = Vec::new();
+        let mut table_stmt = conn.prepare(&format!("select * from [{}]", table_name))?;
+        let mut table_rows = table_stmt.query(NO_PARAMS)?;
+        while let Some(table_row) = table_rows.next()? {
+            out.push(convert_sqlite_row_to_nu_value(table_row, tag.clone())?)
+        }
+        meta_dict.insert_value(
+            "table_name".to_string(),
+            UntaggedValue::Primitive(Primitive::String(table_name)).into_value(tag.clone()),
+        );
+        meta_dict.insert_value(
+            "table_values",
+            UntaggedValue::Table(out).into_value(tag.clone()),
+        );
+        meta_out.push(meta_dict.into_value());
+    }
+    let tag = tag.into();
+    Ok(UntaggedValue::Table(meta_out).into_value(tag))
+}
+
+fn convert_sqlite_row_to_nu_value(
+    row: &Row,
+    tag: impl Into<Tag> + Clone,
+) -> Result<Value, rusqlite::Error> {
+    let mut collected = TaggedDictBuilder::new(tag.clone());
+    for (i, c) in row.columns().iter().enumerate() {
+        collected.insert_value(
+            c.name().to_string(),
+            convert_sqlite_value_to_nu_value(row.get_raw(i), tag.clone()),
+        );
+    }
+    Ok(collected.into_value())
+}
+
+fn convert_sqlite_value_to_nu_value(value: ValueRef, tag: impl Into<Tag> + Clone) -> Value {
+    match value {
+        ValueRef::Null => {
+            UntaggedValue::Primitive(Primitive::String(String::from(""))).into_value(tag)
+        }
+        ValueRef::Integer(i) => UntaggedValue::int(i).into_value(tag),
+        ValueRef::Real(f) => UntaggedValue::decimal(f).into_value(tag),
+        ValueRef::Text(s) => {
+            // this unwrap is safe because we know the ValueRef is Text.
+            UntaggedValue::Primitive(Primitive::String(String::from_utf8_lossy(s).to_string()))
+                .into_value(tag)
+        }
+        ValueRef::Blob(u) => UntaggedValue::binary(u.to_owned()).into_value(tag),
+    }
+}
+
+pub fn from_sqlite_bytes_to_value(
+    mut bytes: Vec<u8>,
+    tag: impl Into<Tag> + Clone,
+) -> Result<Value, std::io::Error> {
+    // FIXME: should probably write a sqlite virtual filesystem
+    // that will allow us to use bytes as a file to avoid this
+    // write out, but this will require C code. Might be
+    // best done as a PR to rusqlite.
+    let mut tempfile = tempfile::NamedTempFile::new()?;
+    tempfile.write_all(bytes.as_mut_slice())?;
+    match convert_sqlite_file_to_nu_value(tempfile.path(), tag) {
+        Ok(value) => Ok(value),
+        Err(e) => Err(std::io::Error::new(std::io::ErrorKind::Other, e)),
+    }
+}
+
+pub fn from_sqlite(bytes: Vec<u8>, name_tag: Tag) -> Result<Vec<ReturnValue>, ShellError> {
+    match from_sqlite_bytes_to_value(bytes, name_tag.clone()) {
+        Ok(x) => match x {
+            Value {
+                value: UntaggedValue::Table(list),
+                ..
+            } => Ok(list.into_iter().map(ReturnSuccess::value).collect()),
+            _ => Ok(vec![ReturnSuccess::value(x)]),
+        },
+        Err(_) => Err(ShellError::labeled_error(
+            "Could not parse as SQLite",
+            "input cannot be parsed as SQLite",
+            &name_tag,
+        )),
+    }
+}

crates/nu_plugin_from_sqlite/src/lib.rs

@@ -0,0 +1,4 @@
+mod from_sqlite;
+mod nu;
+
+pub use from_sqlite::FromSqlite;

crates/nu_plugin_from_sqlite/src/main.rs

@@ -0,0 +1,6 @@
+use nu_plugin::serve_plugin;
+use nu_plugin_from_sqlite::FromSqlite;
+
+fn main() {
+    serve_plugin(&mut FromSqlite::new())
+}

crates/nu_plugin_from_sqlite/src/nu/mod.rs

@@ -0,0 +1,46 @@
+#[cfg(test)]
+mod tests;
+
+use crate::FromSqlite;
+use nu_errors::ShellError;
+use nu_plugin::Plugin;
+use nu_protocol::{CallInfo, Primitive, ReturnValue, Signature, UntaggedValue, Value};
+use nu_source::Tag;
+
+impl Plugin for FromSqlite {
+    fn config(&mut self) -> Result<Signature, ShellError> {
+        Ok(Signature::build("from sqlite")
+            .desc("Convert from sqlite binary into table")
+            .filter())
+    }
+
+    fn begin_filter(&mut self, call_info: CallInfo) -> Result<Vec<ReturnValue>, ShellError> {
+        self.name_tag = call_info.name_tag;
+        Ok(vec![])
+    }
+
+    fn filter(&mut self, input: Value) -> Result<Vec<ReturnValue>, ShellError> {
+        match input {
+            Value {
+                value: UntaggedValue::Primitive(Primitive::Binary(b)),
+                ..
+            } => {
+                self.state.extend_from_slice(&b);
+            }
+            Value { tag, .. } => {
+                return Err(ShellError::labeled_error_with_secondary(
+                    "Expected binary from pipeline",
+                    "requires binary input",
+                    self.name_tag.clone(),
+                    "value originates from here",
+                    tag,
+                ));
+            }
+        }
+        Ok(vec![])
+    }
+
+    fn end_filter(&mut self) -> Result<Vec<ReturnValue>, ShellError> {
+        crate::from_sqlite::from_sqlite(self.state.clone(), Tag::unknown())
+    }
+}

crates/nu_plugin_from_sqlite/src/nu/tests.rs

@@ -0,0 +1 @@
+mod integration {}