collyvsferret
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.
Ferret is a web scraping system. It aims to simplify data extraction from the web for UI testing, machine learning, analytics and more. ferret allows users to focus on the data. It abstracts away the technical details and complexity of underlying technologies using its own declarative language. It is extremely portable, extensible, and fast.
Features
- Declarative language
- Support of both static and dynamic web pages
- Embeddable
- Extensible
Ferret is always implemented in Python through pyfer
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/")
}
// Example scraper for Google in Ferret:
LET google = DOCUMENT("https://www.google.com/", {
driver: "cdp",
userAgent: "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.87 Safari/537.36"
})
HOVER(google, 'input[name="q"]')
WAIT(RAND(100))
INPUT(google, 'input[name="q"]', @criteria, 30)
WAIT(RAND(100))
CLICK(google, 'input[name="btnK"]')
WAITFOR EVENT "navigation" IN google
WAIT_ELEMENT(google, "#res")
LET results = ELEMENTS(google, X("//*[text() = 'Search Results']/following-sibling::*/*"))
FOR el IN results
RETURN {
title: INNER_TEXT(el, 'h3')?,
description: INNER_TEXT(el, X("//em/parent::*")),
url: ELEMENT(el, 'a')?.attributes.href
}