use indexmap::IndexMap;
use nu_engine::CallExt;
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EngineState, Stack};
use nu_protocol::{
Category, Config, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span,
Spanned, SyntaxShape, Type, Value,
};
use quick_xml::events::{BytesEnd, BytesStart, BytesText, Event};
use std::collections::HashSet;
use std::io::Cursor;
use std::io::Write;
#[derive(Clone)]
pub struct ToXml;
impl Command for ToXml {
fn name(&self) -> &str {
"to xml"
}
fn signature(&self) -> Signature {
Signature::build("to xml")
.input_output_types(vec![(Type::Record(vec![]), Type::String)])
.named(
"pretty",
SyntaxShape::Int,
"Formats the XML text with the provided indentation setting",
Some('p'),
)
.category(Category::Formats)
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Outputs an XML string representing the contents of this table",
example: r#"{ "note": { "children": [{ "remember": {"attributes" : {}, "children": [Event]}}], "attributes": {} } } | to xml"#,
result: Some(Value::test_string(
"<note><remember>Event</remember></note>",
)),
},
Example {
description: "Optionally, formats the text with a custom indentation setting",
example: r#"{ "note": { "children": [{ "remember": {"attributes" : {}, "children": [Event]}}], "attributes": {} } } | to xml -p 3"#,
result: Some(Value::test_string(
"<note>\n <remember>Event</remember>\n</note>",
)),
},
]
}
fn usage(&self) -> &str {
"Convert table into .xml text"
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<nu_protocol::PipelineData, ShellError> {
let head = call.head;
let config = engine_state.get_config();
let pretty: Option<Spanned<i64>> = call.get_flag(engine_state, stack, "pretty")?;
to_xml(input, head, pretty, config)
}
}
pub fn add_attributes<'a>(
element: &mut quick_xml::events::BytesStart<'a>,
attributes: &'a IndexMap<String, String>,
) {
for (k, v) in attributes {
element.push_attribute((k.as_str(), v.as_str()));
}
}
pub fn get_attributes(row: &Value, config: &Config) -> Option<IndexMap<String, String>> {
if let Value::Record { .. } = row {
if let Some(Value::Record { cols, vals, .. }) = row.get_data_by_key("attributes") {
let mut h = IndexMap::new();
for (k, v) in cols.iter().zip(vals.iter()) {
h.insert(k.clone(), v.clone().into_abbreviated_string(config));
}
return Some(h);
}
}
None
}
pub fn get_children(row: &Value) -> Option<Vec<Value>> {
if let Value::Record { .. } = row {
if let Some(Value::List { vals, .. }) = row.get_data_by_key("children") {
return Some(vals);
}
}
None
}
pub fn is_xml_row(row: &Value) -> bool {
if let Value::Record { cols, .. } = &row {
let keys: HashSet<&String> = cols.iter().collect();
let children: String = "children".to_string();
let attributes: String = "attributes".to_string();
return keys.contains(&children) && keys.contains(&attributes) && keys.len() == 2;
}
false
}
pub fn write_xml_events<W: Write>(
current: Value,
writer: &mut quick_xml::Writer<W>,
config: &Config,
) -> Result<(), ShellError> {
match current {
Value::Record { cols, vals, span } => {
for (k, v) in cols.iter().zip(vals.iter()) {
let mut e = BytesStart::new(k);
if !is_xml_row(v) {
return Err(ShellError::GenericError(
"Expected a row with 'children' and 'attributes' columns".to_string(),
"missing 'children' and 'attributes' columns ".to_string(),
Some(span),
None,
Vec::new(),
));
}
let a = get_attributes(v, config);
if let Some(ref a) = a {
add_attributes(&mut e, a);
}
writer
.write_event(Event::Start(e))
.expect("Couldn't open XML node");
let c = get_children(v);
if let Some(c) = c {
for v in c {
write_xml_events(v, writer, config)?;
}
}
writer
.write_event(Event::End(BytesEnd::new(k)))
.expect("Couldn't close XML node");
}
}
Value::List { vals, .. } => {
for v in vals {
write_xml_events(v, writer, config)?;
}
}
_ => {
let s = current.into_abbreviated_string(config);
writer
.write_event(Event::Text(BytesText::from_escaped(s.as_str())))
.expect("Couldn't write XML text");
}
}
Ok(())
}
fn to_xml(
input: PipelineData,
head: Span,
pretty: Option<Spanned<i64>>,
config: &Config,
) -> Result<PipelineData, ShellError> {
let mut w = pretty.as_ref().map_or_else(
|| quick_xml::Writer::new(Cursor::new(Vec::new())),
|p| quick_xml::Writer::new_with_indent(Cursor::new(Vec::new()), b' ', p.item as usize),
);
let value = input.into_value(head);
let value_type = value.get_type();
match write_xml_events(value, &mut w, config) {
Ok(_) => {
let b = w.into_inner().into_inner();
let s = if let Ok(s) = String::from_utf8(b) {
s
} else {
return Err(ShellError::NonUtf8(head));
};
Ok(Value::string(s, head).into_pipeline_data())
}
Err(_) => Err(ShellError::CantConvert(
"XML".into(),
value_type.to_string(),
head,
None,
)),
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn test_examples() {
use crate::test_examples;
test_examples(ToXml {})
}
}