web-core

Shared web infrastructure package for search, scraping, HTTP security, and stealth browsers. Used by knowledge-core and downstream applications.

Installation

# From PyPI
uv add n24q02m-web-core

# Or pin to a specific version
uv add "n24q02m-web-core>=1.0.0"

Quick Usage

SearXNG Search

from web_core.search import ensure_searxng, shutdown_searxng
from web_core.search.client import search

# Start/reuse a SearXNG instance (cross-process singleton)
url = await ensure_searxng()

# Search with retry, deduplication, and domain filtering
results = await search(
    searxng_url=url,
    query="Python async patterns",
    max_results=10,
    include_domains=["docs.python.org"],
)

for r in results:
    print(f"{r.title}: {r.url}")

# Clean shutdown
await shutdown_searxng()

Multi-Strategy Scraping

from web_core.scraper import ScrapingAgent, StrategyRegistry

# Create registry with all available strategies
registry = StrategyRegistry.create_default()
agent = ScrapingAgent(strategies={
    name: registry.get(name)
    for name in registry.list_strategies()
})

# Scrape with automatic strategy escalation
content = await agent.scrape("https://example.com/article")

SSRF-Safe HTTP Client

from web_core.http import safe_httpx_client, is_safe_url

# Validate URL before use
assert is_safe_url("https://example.com")  # True
assert not is_safe_url("http://localhost")  # False (SSRF blocked)

# Create client with automatic SSRF protection + DNS pinning
async with safe_httpx_client() as client:
    resp = await client.get("https://example.com")

URL Utilities

from web_core.http import normalize_url, strip_tracking_params, is_valid_domain

# Normalize for deduplication (lowercase, strip www/tracking/fragment)
normalize_url("https://WWW.Example.COM/page?utm_source=x#section")
# => "https://example.com/page"

# Validate domain names (prevents search operator injection)
is_valid_domain("example.com")   # True
is_valid_domain("localhost")     # False

Architecture

src/web_core/
  __init__.py              -- Public API re-exports
  py.typed                 -- PEP 561 type stub marker
  http/                    -- Layer 1: SSRF-safe HTTP primitives
    client.py              -- safe_httpx_client, DNS pinning, IP validation
    url.py                 -- normalize_url, strip_tracking_params, is_valid_domain
  search/                  -- Layer 2: SearXNG search engine
    client.py              -- search() with retry, dedup, domain filtering
    models.py              -- SearchResult, SearchError dataclasses
    runner.py              -- Cross-process SearXNG singleton manager
  scraper/                 -- Layer 2: Multi-strategy scraping agent
    agent.py               -- ScrapingAgent (LangGraph state machine)
    base.py                -- BaseStrategy ABC, ScrapingResult
    cache.py               -- StrategyCache (per-domain performance tracking)
    registry.py            -- StrategyRegistry with lazy-loaded strategies
    state.py               -- ScrapingState TypedDict, ScrapingError
    strategies/            -- Concrete strategy implementations
      api_direct.py        -- API endpoint detection and direct fetch
      basic_http.py        -- Simple httpx GET with SSRF protection
      captcha.py           -- CapSolver-backed captcha bypass
      headless.py          -- Crawl4AI headless browser rendering
      tls_spoof.py         -- curl_cffi TLS fingerprint spoofing
  browsers/                -- Layer 2: Stealth browser abstraction
    protocol.py            -- BrowserProvider Protocol (structural typing)
    patchright.py          -- Patchright (undetected Playwright) provider

Key Design Decisions

• SSRF protection: All outbound HTTP goes through safe_httpx_client with DNS pinning to prevent DNS rebinding attacks.
• Strategy escalation: The scraping agent tries strategies in cache-recommended order, validates responses, and automatically escalates on failure.
• Cross-process SearXNG: A file-lock singleton ensures exactly one SearXNG instance runs across all Python processes.
• Structural typing: BrowserProvider uses Protocol so implementations don't need inheritance.

Development

Prerequisites

• Python 3.13
• uv
• mise (optional, for task shortcuts)

Setup

git clone git@github.com:n24q02m/web-core.git
cd web-core
uv sync --all-extras
pre-commit install

Commands

# Via mise
mise run setup     # uv sync --all-extras
mise run lint      # ruff check + ruff format --check
mise run test      # pytest with coverage
mise run fix       # auto-fix lint + format

# Direct
uv run ruff check src/ tests/
uv run ruff format --check src/ tests/
uv run ty check src/
uv run pytest --cov -q

Tests

• asyncio_mode = "auto" -- no @pytest.mark.asyncio needed
• Coverage threshold: 95% (enforced in pyproject.toml)
• Test files mirror source module structure under tests/

License

MIT