collyvscrwlr-crawler
Colly is a popular web scraping library for the Go programming language. It's designed to be fast and easy to use, and it provides a simple and flexible API for traversing and extracting information from websites.
Colly supports:
- Concurrent scraping with a simple API
- Automatic handling of cookies and sessions
- Automatic handling of redirects
- Support for parsing HTML and XML
- Support for parsing JSON and binary data
- Support for custom storage (e.g. scraping results to a database)
- Simple JavaScript rendering with Colly's built-in rendering engine.
Colly also provides several optional features, such as support for user-agents, delay between requests, rate-limiting and proxy usage.
Colly's API is quite simple, and it is easy to get started with basic web scraping tasks. It's a good choice for scraping moderate to heavy sites, and it can be useful for a wide range of use cases, such as data mining, content extraction, and more.
Additionally, you can use it together with Goquery, a library that allow you to make jquery like queries on HTML documents and it is often used together with Colly to ease the way of parsing the HTML.
This library provides kind of a framework and a lot of ready to use, so-called steps, that you can use as building blocks, to build your own crawlers and scrapers with.
Some features: - Crawler Politeness innocent (respecting robots.txt, throttling,...) - Load URLs using - a (PSR-18) HTTP client (default is of course Guzzle) - or a headless browser (chrome) to get source after Javascript execution - Get absolute links from HTML documents link - Get sitemaps from robots.txt and get all URLs from those sitemaps - Crawl (load) all pages of a website spider - Use cookies (or don't) cookie - Use any HTTP methods (GET, POST,...) and send any headers or body - Iterate over paginated list pages repeat - Extract data from: - HTML and also XML (using CSS selectors or XPath queries) - JSON (using dot notation) - CSV (map columns) - Extract schema.org structured data in JSON-LD format from HTML documents - Keep memory usage low by using PHP Generators muscle - Cache HTTP responses during development, so you don't have to load pages again and again after every code change - Get logs about what your crawler is doing (accepts any PSR-3 LoggerInterface)
Highlights
Example Use
package main
import (
"fmt"
"github.com/gocolly/colly/v2"
)
func main() {
// Instantiate default collector
c := colly.NewCollector(
// Visit only domains: hackerspaces.org, wiki.hackerspaces.org
colly.AllowedDomains("hackerspaces.org", "wiki.hackerspaces.org"),
)
// On every a element which has href attribute call callback
c.OnHTML("a[href]", func(e *colly.HTMLElement) {
link := e.Attr("href")
// Print link
fmt.Printf("Link found: %q -> %s\n", e.Text, link)
// Visit link found on page
// Only those links are visited which are in AllowedDomains
c.Visit(e.Request.AbsoluteURL(link))
})
// Before making a request print "Visiting ..."
c.OnRequest(func(r *colly.Request) {
fmt.Println("Visiting", r.URL.String())
})
// Start scraping on https://hackerspaces.org
c.Visit("https://hackerspaces.org/")
}
<?php
require_once 'vendor/autoload.php';
use Crwlr\Crawler;
$crawler = new Crawler();
$crawler->get('https://example.com', ['User-Agent' => 'webscraping.fyi']);
// more links can be followed:
$crawler->followLinks();
// and current page can be parsed:
$response = $crawler->response();
$title = $crawler->filter('title')->text();
echo $response->getContent();