use crate::commands::WholeStreamCommand; use crate::prelude::*; use nu_errors::ShellError; use nu_protocol::{Primitive, Signature, TaggedDictBuilder, UntaggedValue, Value}; pub struct FromYAML; #[async_trait] impl WholeStreamCommand for FromYAML { fn name(&self) -> &str { "from yaml" } fn signature(&self) -> Signature { Signature::build("from yaml") } fn usage(&self) -> &str { "Parse text as .yaml/.yml and create table." } async fn run( &self, args: CommandArgs, registry: &CommandRegistry, ) -> Result { from_yaml(args, registry).await } } pub struct FromYML; #[async_trait] impl WholeStreamCommand for FromYML { fn name(&self) -> &str { "from yml" } fn signature(&self) -> Signature { Signature::build("from yml") } fn usage(&self) -> &str { "Parse text as .yaml/.yml and create table." } async fn run( &self, args: CommandArgs, registry: &CommandRegistry, ) -> Result { from_yaml(args, registry).await } } fn convert_yaml_value_to_nu_value( v: &serde_yaml::Value, tag: impl Into, ) -> Result { let tag = tag.into(); let span = tag.span; let err_not_compatible_number = ShellError::labeled_error( "Expected a compatible number", "expected a compatible number", &tag, ); Ok(match v { serde_yaml::Value::Bool(b) => UntaggedValue::boolean(*b).into_value(tag), serde_yaml::Value::Number(n) if n.is_i64() => { UntaggedValue::int(n.as_i64().ok_or_else(|| err_not_compatible_number)?).into_value(tag) } serde_yaml::Value::Number(n) if n.is_f64() => UntaggedValue::decimal_from_float( n.as_f64().ok_or_else(|| err_not_compatible_number)?, span, ) .into_value(tag), serde_yaml::Value::String(s) => UntaggedValue::string(s).into_value(tag), serde_yaml::Value::Sequence(a) => { let result: Result, ShellError> = a .iter() .map(|x| convert_yaml_value_to_nu_value(x, &tag)) .collect(); UntaggedValue::Table(result?).into_value(tag) } serde_yaml::Value::Mapping(t) => { let mut collected = TaggedDictBuilder::new(&tag); for (k, v) in t.iter() { // A ShellError that we re-use multiple times in the Mapping scenario let err_unexpected_map = ShellError::labeled_error( format!("Unexpected YAML:\nKey: {:?}\nValue: {:?}", k, v), "unexpected", tag.clone(), ); match (k, v) { (serde_yaml::Value::String(k), _) => { collected.insert_value(k.clone(), convert_yaml_value_to_nu_value(v, &tag)?); } // Hard-code fix for cases where "v" is a string without quotations with double curly braces // e.g. k = value // value: {{ something }} // Strangely, serde_yaml returns // "value" -> Mapping(Mapping { map: {Mapping(Mapping { map: {String("something"): Null} }): Null} }) (serde_yaml::Value::Mapping(m), serde_yaml::Value::Null) => { return m .iter() .take(1) .collect_vec() .first() .and_then(|e| match e { (serde_yaml::Value::String(s), serde_yaml::Value::Null) => Some( UntaggedValue::string("{{ ".to_owned() + &s + " }}") .into_value(tag), ), _ => None, }) .ok_or(err_unexpected_map); } (_, _) => { return Err(err_unexpected_map); } } } collected.into_value() } serde_yaml::Value::Null => UntaggedValue::Primitive(Primitive::Nothing).into_value(tag), x => unimplemented!("Unsupported yaml case: {:?}", x), }) } pub fn from_yaml_string_to_value(s: String, tag: impl Into) -> Result { let tag = tag.into(); let v: serde_yaml::Value = serde_yaml::from_str(&s).map_err(|x| { ShellError::labeled_error( format!("Could not load yaml: {}", x), "could not load yaml from text", &tag, ) })?; Ok(convert_yaml_value_to_nu_value(&v, tag)?) } async fn from_yaml( args: CommandArgs, registry: &CommandRegistry, ) -> Result { let registry = registry.clone(); let args = args.evaluate_once(®istry).await?; let tag = args.name_tag(); let input = args.input; let concat_string = input.collect_string(tag.clone()).await?; match from_yaml_string_to_value(concat_string.item, tag.clone()) { Ok(x) => match x { Value { value: UntaggedValue::Table(list), .. } => Ok(futures::stream::iter(list).to_output_stream()), x => Ok(OutputStream::one(x)), }, Err(_) => Err(ShellError::labeled_error_with_secondary( "Could not parse as YAML", "input cannot be parsed as YAML", &tag, "value originates from here", &concat_string.tag, )), } } #[cfg(test)] mod tests { use super::ShellError; use super::*; use nu_plugin::row; use nu_plugin::test_helpers::value::string; #[test] fn examples_work_as_expected() -> Result<(), ShellError> { use crate::examples::test as test_examples; Ok(test_examples(FromYAML {})?) } #[test] fn test_problematic_yaml() { struct TestCase { description: &'static str, input: &'static str, expected: Result, } let tt: Vec = vec![ TestCase { description: "Double Curly Braces With Quotes", input: r#"value: "{{ something }}""#, expected: Ok(row!["value".to_owned() => string("{{ something }}")]), }, TestCase { description: "Double Curly Braces Without Quotes", input: r#"value: {{ something }}"#, expected: Ok(row!["value".to_owned() => string("{{ something }}")]), }, ]; for tc in tt.into_iter() { let actual = from_yaml_string_to_value(tc.input.to_owned(), Tag::default()); if actual.is_err() { assert!( tc.expected.is_err(), "actual is Err for test:\nTest Description {}\nErr: {:?}", tc.description, actual ); } else { assert_eq!(actual, tc.expected, "{}", tc.description); } } } }