feat(native): doc loader for common native (#9941)

packages/common/native/src/doc_loader/loader/html.rs

@@ -0,0 +1,87 @@
+use std::{collections::HashMap, io::Cursor};
+
+use serde_json::Value;
+
+/**
+ * modified from https://github.com/Abraxas-365/langchain-rust/tree/v4.6.0/src/document_loaders
+ */
+use super::*;
+#[derive(Debug, Clone)]
+pub struct HtmlLoader<R> {
+  html: R,
+  url: Url,
+}
+
+impl HtmlLoader<Cursor<Vec<u8>>> {
+  pub fn from_string<S: Into<String>>(input: S, url: Url) -> Self {
+    let input = input.into();
+    let reader = Cursor::new(input.into_bytes());
+    Self::new(reader, url)
+  }
+}
+
+impl<R: Read> HtmlLoader<R> {
+  pub fn new(html: R, url: Url) -> Self {
+    Self { html, url }
+  }
+}
+
+impl<R: Read + Send + Sync + 'static> Loader for HtmlLoader<R> {
+  fn load(mut self) -> Result<Vec<Document>, LoaderError> {
+    let cleaned_html = readability::extractor::extract(&mut self.html, &self.url)?;
+    let doc =
+      Document::new(format!("{}\n{}", cleaned_html.title, cleaned_html.text)).with_metadata(
+        HashMap::from([("source".to_string(), Value::from(self.url.as_str()))]),
+      );
+
+    Ok(vec![doc])
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_html_loader() {
+    let input = "<p>Hello world!</p>";
+
+    let html_loader = HtmlLoader::new(
+      input.as_bytes(),
+      Url::parse("https://example.com/").unwrap(),
+    );
+
+    let documents = html_loader.load().unwrap();
+
+    let expected = "\nHello world!";
+
+    assert_eq!(documents.len(), 1);
+    assert_eq!(
+      documents[0].metadata.get("source").unwrap(),
+      &Value::from("https://example.com/")
+    );
+    assert_eq!(documents[0].page_content, expected);
+  }
+
+  #[test]
+  fn test_html_load_from_path() {
+    let buffer = include_bytes!("../../../fixtures/sample.html");
+    let html_loader = HtmlLoader::new(
+      Cursor::new(buffer),
+      Url::parse("https://example.com/").unwrap(),
+    );
+
+    let documents = html_loader.load().unwrap();
+
+    let expected = "Example Domain\n\n        This domain is for use in illustrative examples in \
+                    documents. You may\n        use this domain in literature without prior \
+                    coordination or asking for\n        permission.\n      More information...";
+
+    assert_eq!(documents.len(), 1);
+    assert_eq!(
+      documents[0].metadata.get("source").unwrap(),
+      &Value::from("https://example.com/")
+    );
+    assert_eq!(documents[0].page_content, expected);
+  }
+}