use std::{
collections::HashMap,
fs::File,
io::{BufReader, Cursor, Read},
path::Path,
pin::Pin,
};
use async_trait::async_trait;
use futures::{stream, Stream};
use crate::{
document_loaders::{process_doc_stream, Loader, LoaderError},
schemas::Document,
text_splitter::TextSplitter,
};
#[derive(Debug, Clone)]
pub struct MarkdownLoader<R> {
reader: R,
}
impl<R: Read> MarkdownLoader<R> {
pub fn new(reader: R) -> Self {
Self { reader }
}
}
impl MarkdownLoader<Cursor<Vec<u8>>> {
pub fn from_string<S: Into<String>>(input: S) -> Self {
let input = input.into();
let reader = Cursor::new(input.into_bytes());
Self::new(reader)
}
}
impl MarkdownLoader<BufReader<File>> {
pub fn from_path<P: AsRef<Path>>(path: P) -> Result<Self, LoaderError> {
let file = File::open(path)?;
let reader = BufReader::new(file);
Ok(Self::new(reader))
}
}
#[async_trait]
impl<R: Read + Send + Sync + 'static> Loader for MarkdownLoader<R> {
async fn load(
mut self,
) -> Result<
Pin<Box<dyn Stream<Item = Result<Document, LoaderError>> + Send + 'static>>,
LoaderError,
> {
let mut content = String::new();
self.reader.read_to_string(&mut content)?;
let mut metadata = HashMap::new();
metadata.insert(
"source_type".to_string(),
serde_json::Value::from("markdown"),
);
let doc = Document::new(content).with_metadata(metadata);
let stream = stream::iter(vec![Ok(doc)]);
Ok(Box::pin(stream))
}
async fn load_and_split<TS: TextSplitter + 'static>(
mut self,
splitter: TS,
) -> Result<
Pin<Box<dyn Stream<Item = Result<Document, LoaderError>> + Send + 'static>>,
LoaderError,
> {
let doc_stream = self.load().await?;
let stream = process_doc_stream(doc_stream, splitter).await;
Ok(Box::pin(stream))
}
}
#[cfg(test)]
mod tests {
use futures_util::StreamExt;
use super::*;
#[tokio::test]
async fn test_markdown_loader() {
let input = "# Title\n\nThis is a paragraph with **bold** text.";
let loader = MarkdownLoader::from_string(input);
let documents = loader
.load()
.await
.unwrap()
.map(|x| x.unwrap())
.collect::<Vec<_>>()
.await;
assert_eq!(documents.len(), 1);
assert!(documents[0].page_content.contains("Title"));
assert!(documents[0].page_content.contains("bold"));
}
}