use crate::dataframe::values::{Column, NuDataFrame};
use chrono::DateTime;
use nu_engine::command_prelude::*;
use polars::prelude::{IntoSeries, StringMethods, TimeUnit};
#[derive(Clone)]
pub struct AsDateTime;
impl Command for AsDateTime {
fn name(&self) -> &str {
"dfr as-datetime"
}
fn usage(&self) -> &str {
r#"Converts string to datetime."#
}
fn extra_usage(&self) -> &str {
r#"Format example:
"%y/%m/%d %H:%M:%S" => 21/12/31 12:54:98
"%y-%m-%d %H:%M:%S" => 2021-12-31 24:58:01
"%y/%m/%d %H:%M:%S" => 21/12/31 24:58:01
"%y%m%d %H:%M:%S" => 210319 23:58:50
"%Y/%m/%d %H:%M:%S" => 2021/12/31 12:54:98
"%Y-%m-%d %H:%M:%S" => 2021-12-31 24:58:01
"%Y/%m/%d %H:%M:%S" => 2021/12/31 24:58:01
"%Y%m%d %H:%M:%S" => 20210319 23:58:50
"%FT%H:%M:%S" => 2019-04-18T02:45:55
"%FT%H:%M:%S.%6f" => microseconds
"%FT%H:%M:%S.%9f" => nanoseconds"#
}
fn signature(&self) -> Signature {
Signature::build(self.name())
.required("format", SyntaxShape::String, "formatting date time string")
.switch("not-exact", "the format string may be contained in the date (e.g. foo-2021-01-01-bar could match 2021-01-01)", Some('n'))
.input_output_type(
Type::Custom("dataframe".into()),
Type::Custom("dataframe".into()),
)
.category(Category::Custom("dataframe".into()))
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Converts string to datetime",
example: r#"["2021-12-30 00:00:00" "2021-12-31 00:00:00"] | dfr into-df | dfr as-datetime "%Y-%m-%d %H:%M:%S""#,
result: Some(
NuDataFrame::try_from_columns(
vec![Column::new(
"datetime".to_string(),
vec![
Value::date(
DateTime::parse_from_str(
"2021-12-30 00:00:00 +0000",
"%Y-%m-%d %H:%M:%S %z",
)
.expect("date calculation should not fail in test"),
Span::test_data(),
),
Value::date(
DateTime::parse_from_str(
"2021-12-31 00:00:00 +0000",
"%Y-%m-%d %H:%M:%S %z",
)
.expect("date calculation should not fail in test"),
Span::test_data(),
),
],
)],
None,
)
.expect("simple df for test should not fail")
.into_value(Span::test_data()),
),
},
Example {
description: "Converts string to datetime with high resolutions",
example: r#"["2021-12-30 00:00:00.123456789" "2021-12-31 00:00:00.123456789"] | dfr into-df | dfr as-datetime "%Y-%m-%d %H:%M:%S.%9f""#,
result: Some(
NuDataFrame::try_from_columns(
vec![Column::new(
"datetime".to_string(),
vec![
Value::date(
DateTime::parse_from_str(
"2021-12-30 00:00:00.123456789 +0000",
"%Y-%m-%d %H:%M:%S.%9f %z",
)
.expect("date calculation should not fail in test"),
Span::test_data(),
),
Value::date(
DateTime::parse_from_str(
"2021-12-31 00:00:00.123456789 +0000",
"%Y-%m-%d %H:%M:%S.%9f %z",
)
.expect("date calculation should not fail in test"),
Span::test_data(),
),
],
)],
None,
)
.expect("simple df for test should not fail")
.into_value(Span::test_data()),
),
},
]
}
fn run(
&self,
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
command(engine_state, stack, call, input)
}
}
fn command(
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let format: String = call.req(engine_state, stack, 0)?;
let not_exact = call.has_flag(engine_state, stack, "not-exact")?;
let df = NuDataFrame::try_from_pipeline(input, call.head)?;
let series = df.as_series(call.head)?;
let casted = series.str().map_err(|e| ShellError::GenericError {
error: "Error casting to string".into(),
msg: e.to_string(),
span: Some(call.head),
help: None,
inner: vec![],
})?;
let res = if not_exact {
casted.as_datetime_not_exact(
Some(format.as_str()),
TimeUnit::Nanoseconds,
false,
None,
&Default::default(),
)
} else {
casted.as_datetime(
Some(format.as_str()),
TimeUnit::Nanoseconds,
false,
false,
None,
&Default::default(),
)
};
let mut res = res
.map_err(|e| ShellError::GenericError {
error: "Error creating datetime".into(),
msg: e.to_string(),
span: Some(call.head),
help: None,
inner: vec![],
})?
.into_series();
res.rename("datetime");
NuDataFrame::try_from_series(vec![res], call.head)
.map(|df| PipelineData::Value(NuDataFrame::into_value(df, call.head), None))
}
#[cfg(test)]
mod test {
use super::super::super::super::test_dataframe::test_dataframe;
use super::*;
#[test]
fn test_examples() {
test_dataframe(vec![Box::new(AsDateTime {})])
}
}