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scraper-rs

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Python bindings for the Rust scraper crate via PyO3. It provides a lightweight Document/Element API with CSS selectors, XPath (via xee-xpath), handy helpers, and zero Python-side parsing work.

Quick start

from scraper_rs import Document, first, prettify, select, select_first, xpath

html = """
<html><body>
  <div class="item" data-id="1"><a href="/a">First</a></div>
  <div class="item" data-id="2"><a href="/b">Second</a></div>
</body></html>
"""

doc = Document(html)
print(doc.text)  # "First Second"

items = doc.select(".item")
print(items[0].attr("data-id"))  # "1"
print(items[0].to_dict())        # {"tag": "div", "text": "First", "html": "<a...>", ...}

first_link = doc.select_first("a[href]")  # alias: doc.find(...)
print(first_link.text, first_link.attr("href"))  # First /a
links_within_first = first_link.select("a[href]")
print([link.attr("href") for link in links_within_first])  # ["/a"]

# XPath (element results only)
xpath_items = doc.xpath("//div[@class='item']/a")
print([link.text for link in xpath_items])  # ["First", "Second"]
print(doc.xpath_first("//div[@data-id='1']/a").attr("href"))  # "/a"

# Functional helpers
links = select(html, "a[href]")
print([link.attr("href") for link in links])  # ["/a", "/b"]
print(first(html, "a[href]").text)            # First
print(select_first(html, "a[href]").text)     # First
print([link.text for link in xpath(html, "//div[@class='item']/a")])  # ["First", "Second"]
print(prettify(html))

For runnable samples, see examples/demo.py and examples/demo_prettify_url.py. Quick URL prettify demo:

python examples/demo_prettify_url.py https://example.com --max-lines 80

Async usage

The scraper_rs.asyncio module keeps the event loop responsive. parse yields once (asyncio.sleep(0)) before constructing a sync Document in the current thread, while select/xpath helpers run in a thread pool. Parsed documents and elements are wrapped with awaitable selector methods for nested queries:

import asyncio
from scraper_rs import asyncio as scraping_async

html = "<div class='item'><a href='/a'>First</a></div>"


async def main():
    async with await scraping_async.parse(html) as doc:
        items = await doc.select(".item")
        first_link = await items[0].select_first("a[href]")
        print(first_link.text)  # First

    links = await scraping_async.select(html, "a[href]")
    print([link.attr("href") for link in links])  # ["/a"]


asyncio.run(main())

All async functions accept the same keyword arguments as their sync counterparts (max_size_bytes, truncate_on_limit, etc.). Async wrappers expose the underlying sync objects via .document and .element if you need direct access. AsyncDocument supports async with for automatic cleanup in coroutine code.

Large documents and memory safety

To avoid runaway allocations, parsing defaults to a 1 GiB cap. Pass max_size_bytes to override:

from scraper_rs import Document, select

doc = Document(html, max_size_bytes=5_000_000)  # 5 MB guard
links = select(html, "a[href]", max_size_bytes=5_000_000)

If you want to parse a limited portion of an oversized HTML document instead of rejecting it entirely, use truncate_on_limit=True:

# Parse only the first 100KB of a large HTML document
doc = Document(large_html, max_size_bytes=100_000, truncate_on_limit=True)
links = doc.select("a[href]")  # Will only find links in the first 100KB

# Also works with top-level functions
items = select(large_html, ".item", max_size_bytes=100_000, truncate_on_limit=True)

Note: Truncation happens at valid UTF-8 character boundaries to prevent encoding errors.

API highlights

  • Document(html: str) / Document.from_html(html) parse HTML for CSS and keep the DOM; XPath parsing is initialized lazily on first XPath query.
  • .select(css)list[Element], .select_first(css) / .find(css) → first Element | None, .css(css) is an alias.
  • .xpath(expr) / .xpath_first(expr) evaluate XPath expressions that return element nodes.
  • .prettify() renders the current DOM as an indented string for readable output/debugging.
  • .text returns normalized text; Document.html is the original input HTML; Element.html is inner HTML.
  • scraper_rs.asyncio exposes async parse/select/xpath wrappers to keep the event loop responsive.
  • Element exposes .tag, .text, .html, .attrs plus helpers .attr(name), .get(name, default), .to_dict().
  • Elements support nested CSS and XPath selection via .select(css), .select_first(css), .find(css), .css(css), .xpath(expr), .xpath_first(expr).
  • Elements also expose .prettify() to format element HTML with indentation.
  • Top-level helpers mirror the class methods: parse(html), prettify(html), select(html, css), select_first(html, css) / first(html, css), xpath(html, expr), xpath_first(html, expr).
  • max_size_bytes lets you fail fast on oversized HTML; defaults to a 1 GiB limit.
  • truncate_on_limit allows parsing a truncated version (limited to max_size_bytes) of oversized HTML instead of raising an error.
  • Call doc.close() (or with Document(html) as doc: ...) to free parsed DOM resources when you're done.
  • In async workflows, use async with await scraper_rs.asyncio.parse(html) as doc: ... for automatic AsyncDocument cleanup.

Installation

Built wheels target abi3 (CPython 3.10+). To build locally:

# Install maturin (uv is used in this repo, but pip works too)
pip install maturin

# Build a wheel
maturin build --release --compatibility linux

# Install the generated wheel
pip install target/wheels/scraper_rust-*.whl

If you have just installed, the repo includes helpers: just build (local wheel), just install-wheel (install the built wheel), and just build_manylinux (via the official maturin Docker image).

Projects Using scraper-rs

  • silkworm - Async web scraping framework on top of Rust

Development

Requirements: Rust toolchain, Python 3.10+, maturin, pytest, and pytest-asyncio for tests.

  • Run tests: just test or uv run pytest tests/
  • Format code: just fmt (or cargo fmt --all and uv run ruff format)
  • Lint Rust: just lint (or cargo clippy --all-targets --all-features -- -D warnings)
  • The PyO3 module name is scraper_rs; the Rust crate is built as cdylib.

Contributions and issues are welcome. If you add public API, please extend tests/test_scraper.py and the example script accordingly.