forked from gocolly/colly
/
parallel.go
39 lines (33 loc) · 966 Bytes
/
parallel.go
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package main
import (
"fmt"
"github.com/gocolly/colly"
)
func main() {
// Instantiate default collector
c := colly.NewCollector(
// MaxDepth is 2, so only the links on the scraped page
// and links on those pages are visited
colly.MaxDepth(2),
colly.Async(true),
)
// Limit the maximum parallelism to 2
// This is necessary if the goroutines are dynamically
// created to control the limit of simultaneous requests.
//
// Parallelism can be controlled also by spawning fixed
// number of go routines.
c.Limit(&colly.LimitRule{DomainGlob: "*", Parallelism: 2})
// 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.Println(link)
// Visit link found on page on a new thread
e.Request.Visit(link)
})
// Start scraping on https://en.wikipedia.org
c.Visit("https://en.wikipedia.org/")
// Wait until threads are finished
c.Wait()
}