A Rust library for extracting main content from web pages using text density analysis. This is an implementation of the Content Extraction via Text Density (CETD) algorithm described in the paper by Fei Sun, Dandan Song and Lejian Liao: Content Extraction via Text Density.
Web pages often contain a lot of peripheral content like navigation menus, advertisements, footers, and sidebars. This makes it challenging to extract just the main content programmatically. This library helps solve this problem by:
- Analyzing the text density patterns in HTML documents
- Identifying content-rich sections versus navigational/peripheral elements
- Extracting the main content while filtering out noise
- Handling various HTML layouts and structures
- Build a density tree representing text distribution in the HTML document
- Calculate composite text density using multiple metrics
- Extract main content blocks based on density patterns
- Support for nested HTML structures
- Efficient processing of large documents
- Error handling for malformed HTML
Due to "LazyLock" MSRV is 1.80
Basic usage example:
use scraper::Html;
use dom_content_extraction::get_content;
fn main() {
let html = r#"<!DOCTYPE html><html><body>
<nav>Home | About</nav>
<main>
<article>
<h1>Main Article</h1>
<p>This is the primary content that contains enough text to maintain proper density metrics. The paragraph needs sufficient length to establish text-to-link ratio.</p>
<p>Second paragraph adds more textual density to ensure the content extraction algorithm works correctly.</p>
<a href="\#">Related link</a>
</article>
</main>
<footer>Copyright 2024</footer>
</body></html>"#;
let document = Html::parse_document(html);
let content = get_content(&document).unwrap();
println!("{}", content);
}Add it it with:
cargo add dom-content-extractionor add to you Cargo.toml
dom-content-extraction = "0.3"
Read the docs!
dom-content-extraction documentation
Check examples.
This one will extract content from generated "lorem ipsum" page
cargo run --example check -- lorem-ipsum This one print node with highest density:
cargo run --examples check -- test4There is scoring example i'm trying to implement scoring. You will need to download GoldenStandard and finalrun-input datasets from:
https://sigwac.org.uk/cleaneval/
and unpack archives into data/ directory.
cargo run --example ce_scoreAs far as i see there is problem opening some files:
Error processing file 730: Failed to read file: "data/finalrun-input/730.html"
Caused by:
stream did not contain valid UTF-8But overall extraction works pretty well:
Overall Performance:
Files processed: 370
Average Precision: 0.87
Average Recall: 0.82
Average F1 Score: 0.75
The crate includes a command-line binary tool dce (DOM Content Extraction) for extracting main content from HTML documents. It supports both local files and remote URLs as input sources.
The binary is included by default. You can install it using cargo:
cargo install dom-content-extractiondce [OPTIONS]
Options:
-u, --url <URL> URL to fetch HTML content from
-f, --file <FILE> Local HTML file to process
-o, --output <FILE> Output file (stdout if not specified)
-h, --help Print help
-V, --version Print version
Note: Either --url or --file must be specified, but not both.
- URL Fetching: Automatically downloads HTML content from specified URLs
- Timeout Control: 30-second timeout for URL fetching to prevent hangs
- Error Handling: Comprehensive error messages for common failure cases
- Flexible Output: Write to file or stdout
- Temporary File Management: Automatic cleanup of downloaded content
Extract content from a URL and print to stdout:
dce --url "https://example.com/article"Process a local HTML file and save to output file:
dce --file input.html --output extracted.txtExtract from URL and save directly to file:
dce --url "https://example.com/page" --output content.txtThe binary provides clear error messages for common scenarios:
- Invalid URLs
- Network timeouts
- File access issues
- HTML parsing errors
- Content extraction failures
The binary functionality requires the following additional dependencies:
clap: Command-line argument parsingreqwest: HTTP client for URL fetchingtempfile: Temporary file managementurl: URL parsing and validationanyhow: Error handling
These dependencies are only included when building with the default cli feature.