Skip to content

Package chromedp is a faster, simpler way to drive browsers (Chrome, Edge, Safari, Android, etc) without external dependencies (ie, Selenium, PhantomJS, etc).

License

Notifications You must be signed in to change notification settings

keijiyoshida/chromedp

 
 

Repository files navigation

About chromedp

Package chromedp is a faster, simpler way to drive browsers in Go using the Chrome Debugging Protocol (for Chrome, Edge, Safari, etc) without external dependencies (ie, Selenium, PhantomJS, etc).

NOTE: chromedp's API is currently unstable, and may change at a moments notice. There are likely extremely bad bugs lurking in this code. CAVEAT USER.

Installation

Install in the usual way:

go get -u github.com/knq/chromedp

Usage

Below is a simple Google search performed using chromedp (taken from examples/simple):

This example shows logic for a simple search for a known website, clicking on the right link, and then taking a screenshot of a specific element on the loaded page and saving that to a local file on disk.

package main

import (
	"context"
	"fmt"
	"io/ioutil"
	"log"
	"time"

	cdp "github.com/knq/chromedp"
	cdptypes "github.com/knq/chromedp/cdp"
)

func main() {
	var err error

	// create context
	ctxt, cancel := context.WithCancel(context.Background())
	defer cancel()

	// create chrome instance
	c, err := cdp.New(ctxt)
	if err != nil {
		log.Fatal(err)
	}

	// run task list
	var site, res string
	err = c.Run(ctxt, googleSearch("site:brank.as", "Easy Money Management", &site, &res))
	if err != nil {
		log.Fatal(err)
	}

	// shutdown chrome
	err = c.Shutdown(ctxt)
	if err != nil {
		log.Fatal(err)
	}

	// wait for chrome to finish
	err = c.Wait()
	if err != nil {
		log.Fatal(err)
	}

	log.Printf("saved screenshot of #testimonials from search result listing `%s` (%s)", res, site)
}

func googleSearch(q, text string, site, res *string) cdp.Tasks {
	var buf []byte
	sel := fmt.Sprintf(`//a[text()[contains(., '%s')]]`, text)
	return cdp.Tasks{
		cdp.Navigate(`https://www.google.com`),
		cdp.Sleep(2 * time.Second),
		cdp.WaitVisible(`#hplogo`, cdp.ByID),
		cdp.SendKeys(`#lst-ib`, q, cdp.ByID),
		cdp.Click(`input[name="btnK"]`, cdp.ByQuery),
		cdp.WaitNotVisible(`input[name="btnI"]`, cdp.ByQuery),
		cdp.Text(sel, res),
		cdp.Click(sel),
		cdp.Sleep(2 * time.Second),
		cdp.WaitVisible(`#footer`, cdp.ByQuery),
		cdp.WaitNotVisible(`div.v-middle > div.la-ball-clip-rotate`, cdp.ByQuery),
		cdp.Location(site),
		cdp.Screenshot(`#testimonials`, &buf, cdp.ByID),
		cdp.ActionFunc(func(context.Context, cdptypes.FrameHandler) error {
			return ioutil.WriteFile("testimonials.png", buf, 0644)
		}),
	}
}

Please see the examples directory for examples.

TODO

  • Move timeouts to context (defaults)
  • Implement more query selector options (allow over riding context timeouts)
  • Contextual actions for "dry run" (or via an accumulator?)
  • Network loader / manager
  • More examples
  • Profiler
  • Unit tests / coverage: travis-ci + coveralls integration

About

Package chromedp is a faster, simpler way to drive browsers (Chrome, Edge, Safari, Android, etc) without external dependencies (ie, Selenium, PhantomJS, etc).

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published

Languages

  • Go 99.8%
  • Other 0.2%