Is Crawlee Python as feature-complete as the JavaScript version?
Crawlee Python is rapidly maturing but is not yet as feature-complete as the JavaScript version. While both versions share the same core philosophy and architecture, the JavaScript version has a significant head start in development and offers a broader feature set. However, the Python version includes all essential features needed for production web scraping and is actively catching up.
Current Feature Parity Status
Features Available in Both Versions
Both Crawlee Python and JavaScript support the core functionality that makes Crawlee powerful:
Crawler Types:
- BeautifulSoupCrawler
(Python) / CheerioCrawler
(JavaScript) - Fast HTML parsing
- PlaywrightCrawler
(both) - Browser automation for JavaScript-rendered pages
- HttpCrawler
(both) - Low-level HTTP requests with full control
Core Features: - Automatic request queue management - Smart request retry logic with exponential backoff - Session management and cookie handling - Proxy rotation support - Request storage and data persistence - Configurable concurrency controls - Request filtering and deduplication - Automatic rate limiting and politeness policies
Data Management: - Dataset storage (structured data export) - Key-value store (arbitrary data persistence) - Request queue (distributed crawling support)
JavaScript-Exclusive Features
The JavaScript version currently has several advanced features not yet available in Python:
Advanced Crawlers:
- PuppeteerCrawler
- While Python has PlaywrightCrawler, Puppeteer-specific implementation is JavaScript-only
- JSDOMCrawler
- Lightweight DOM simulation
Enhanced Features: - More mature adaptive crawling algorithms - Advanced browser pool management - Comprehensive cloud integration (Apify platform) - More extensive middleware system - Better TypeScript type definitions - More plugin ecosystem options
Development Tools: - More comprehensive CLI tools - Advanced debugging utilities - Browser snapshot features for development
Practical Comparison: Code Examples
Python Version Example
from crawlee.playwright_crawler import PlaywrightCrawler, PlaywrightCrawlingContext
async def main():
crawler = PlaywrightCrawler(
max_requests_per_crawl=100,
headless=True,
)
@crawler.router.default_handler
async def request_handler(context: PlaywrightCrawlingContext) -> None:
# Extract data from the page
data = await context.page.evaluate('''() => {
return {
title: document.querySelector('h1')?.textContent,
items: Array.from(document.querySelectorAll('.item')).map(el => ({
name: el.querySelector('.name')?.textContent,
price: el.querySelector('.price')?.textContent
}))
}
}''')
# Push data to dataset
await context.push_data(data)
# Enqueue new requests
await context.enqueue_links(selector='a.next-page')
await crawler.run(['https://example.com/products'])
if __name__ == '__main__':
import asyncio
asyncio.run(main())
JavaScript Version Example
import { PlaywrightCrawler } from 'crawlee';
const crawler = new PlaywrightCrawler({
maxRequestsPerCrawl: 100,
headless: true,
async requestHandler({ page, request, enqueueLinks, pushData }) {
// Extract data from the page
const data = await page.evaluate(() => {
return {
title: document.querySelector('h1')?.textContent,
items: Array.from(document.querySelectorAll('.item')).map(el => ({
name: el.querySelector('.name')?.textContent,
price: el.querySelector('.price')?.textContent
}))
};
});
// Push data to dataset
await pushData(data);
// Enqueue new requests
await enqueueLinks({ selector: 'a.next-page' });
},
});
await crawler.run(['https://example.com/products']);
As you can see, the API design is remarkably similar, making it easier to switch between versions if needed.
Performance Considerations
Python Version Performance
from crawlee.beautifulsoup_crawler import BeautifulSoupCrawler
async def main():
# Python version excels with BeautifulSoup for static content
crawler = BeautifulSoupCrawler(
max_requests_per_crawl=1000,
max_request_retries=3,
# Concurrency control
max_concurrency=50,
)
@crawler.router.default_handler
async def handler(context):
# Fast HTML parsing with BeautifulSoup
title = context.soup.select_one('h1').get_text()
await context.push_data({'title': title})
await crawler.run(['https://example.com'])
Performance Characteristics: - BeautifulSoup parsing is generally faster than Cheerio for simple tasks - Python's async/await implementation performs well for I/O-bound operations - Lower memory footprint for simple crawling tasks - Excellent integration with Python's data science ecosystem (pandas, numpy)
JavaScript Version Performance
import { CheerioCrawler } from 'crawlee';
const crawler = new CheerioCrawler({
maxRequestsPerCrawl: 1000,
maxRequestRetries: 3,
maxConcurrency: 50,
async requestHandler({ $, request, pushData }) {
// Fast HTML parsing with Cheerio
const title = $('h1').text();
await pushData({ title });
},
});
await crawler.run(['https://example.com']);
Performance Characteristics: - Cheerio (jQuery-like) is extremely fast for DOM manipulation - Node.js event loop excels at high-concurrency scenarios - Better performance with browser automation at scale - More mature optimization strategies
Browser Automation Comparison
Both versions support browser automation for modern web scraping, but with slight differences:
Python with Playwright
from crawlee.playwright_crawler import PlaywrightCrawler
async def main():
crawler = PlaywrightCrawler(
browser_type='chromium',
headless=True,
browser_pool_options={
'max_pages_per_browser': 10,
}
)
@crawler.router.default_handler
async def handler(context):
# Wait for dynamic content
await context.page.wait_for_selector('.dynamic-content')
# Handle authentication if needed
await context.page.fill('#username', 'user')
await context.page.fill('#password', 'pass')
await context.page.click('button[type="submit"]')
data = await context.page.inner_text('.result')
await context.push_data({'result': data})
await crawler.run(['https://example.com'])
JavaScript with Playwright
import { PlaywrightCrawler } from 'crawlee';
const crawler = new PlaywrightCrawler({
browserPoolOptions: {
maxPagesPerBrowser: 10,
},
async requestHandler({ page, pushData }) {
// Wait for dynamic content
await page.waitForSelector('.dynamic-content');
// Handle authentication
await page.fill('#username', 'user');
await page.fill('#password', 'pass');
await page.click('button[type="submit"]');
const data = await page.innerText('.result');
await pushData({ result: data });
},
});
await crawler.run(['https://example.com']);
Ecosystem and Community
Python Advantages
- Rich Data Science Integration: Seamless integration with pandas, numpy, scikit-learn
- Growing Community: Python's dominance in data science attracts more scraping developers
- Familiar Syntax: Python's readability appeals to data scientists and analysts
- Library Compatibility: Easy integration with popular Python libraries (requests, httpx, aiohttp)
JavaScript Advantages
- Mature Ecosystem: Longer development time means more plugins and extensions
- Apify Platform: Deep integration with Apify's cloud scraping platform
- NPM Packages: Access to vast npm ecosystem
- Browser Native: JavaScript naturally integrates with browser automation tools
- Community Size: Larger user base means more examples and solutions
Installation and Setup
Python Installation
# Install from PyPI
pip install crawlee
# Install with Playwright support
pip install 'crawlee[playwright]'
# Install Playwright browsers
playwright install
# Verify installation
python -c "import crawlee; print(crawlee.__version__)"
JavaScript Installation
# Install from npm
npm install crawlee
# Install with Playwright
npm install crawlee playwright
# Verify installation
npx crawlee --version
Which Version Should You Choose?
Choose Python If:
- You're working primarily in Python ecosystems
- You need tight integration with data science libraries (pandas, numpy)
- Your team is more comfortable with Python syntax
- You're building data pipelines that connect to Python-based tools
- You need the essential features but don't require cutting-edge capabilities
Choose JavaScript If:
- You need the most advanced features and latest updates
- You're deploying to Apify platform
- You're comfortable with TypeScript/JavaScript
- You need the most mature browser automation
- You want access to the largest plugin ecosystem
- You're building high-performance, high-concurrency crawlers
Migration Path
If you start with one version and need to switch, the similar API design makes migration straightforward:
# Python pattern
@crawler.router.default_handler
async def handler(context):
data = await context.page.evaluate('() => ({ title: document.title })')
await context.push_data(data)
// JavaScript equivalent
async requestHandler({ page, pushData }) {
const data = await page.evaluate(() => ({ title: document.title }));
await pushData(data);
}
Future Roadmap
The Crawlee team is actively working to achieve feature parity between Python and JavaScript versions. Expected improvements for Python include:
- Enhanced browser pool management
- More sophisticated adaptive crawling
- Additional crawler types
- Improved cloud platform integration
- More comprehensive middleware system
Conclusion
While Crawlee Python isn't yet as feature-complete as the JavaScript version, it provides all the essential functionality needed for professional web scraping projects. The Python version is production-ready, well-maintained, and rapidly improving. For most use cases, the choice between versions should be based on your existing tech stack, team expertise, and specific feature requirements rather than feature completeness alone.
Both versions share the same excellent architecture, making Crawlee a solid choice for handling browser sessions regardless of which language you prefer.