datu 0.3.4

datu - a data file utility
Documentation 
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use async_trait::async_trait;

use crate::Result;
use crate::pipeline::RecordBatchReaderSource;
use crate::pipeline::Step;
use crate::pipeline::display::write_record_batches_as_yaml;
use crate::pipeline::write::WriteYamlArgs;

/// Pipeline step that writes record batches to a YAML file (sequence of row objects).
pub struct WriteYamlStep {
    pub args: WriteYamlArgs,
    pub source: RecordBatchReaderSource,
}

#[async_trait(?Send)]
impl Step for WriteYamlStep {
    type Input = ();
    type Output = ();

    async fn execute(self, _input: Self::Input) -> Result<Self::Output> {
        let path = self.args.path.as_str();
        let file = std::fs::File::create(path)?;
        let mut source = self.source;
        let mut reader = source.get().await?;
        write_record_batches_as_yaml(&mut *reader, file, self.args.sparse)?;
        Ok(())
    }
}