Google Chrome Debugger (GCD)

This is primarly an auto-generated client library for communicating with a Google Chrome Browser over their remote client debugger protocol. Note that their documentation is partially incorrect and does not contain a lot of the API calls that are actually available.

Because I'm lazy and there are hundereds of different custom types and API methods, this library has been primarly automatically generated using their protocol.json. What this means is probably a lot of stuff doesn't work.

The gcdprotogen package was created to generate types and commands for gcd. Non-biolerplate code (and the majority of the logic) are in gcd.go and chrome_target.go.

The API

The API consists of three types, synchronous requests, asynchronous requests and events. Synchronous requests are handled by using non-buffered channels and methods can be called and will return once the value is available. Asynchronous requests have not been heavily tested. Events are handled by subscribing the response method type and calling the API's "Enable()" such as:

	console := targets[0].Console()
	targets[0].Subscribe("Console.messageAdded", func(target *ChromeTarget, v []byte) {
		msg := &EventData{}
		err := json.Unmarshal(v, msg)
		if err != nil {
			log.Fatalf("error unmarshalling event data: %v\n", err)
		}
		fmt.Printf("METHOD: %s\n", msg.Method)
		eventData := msg.Params.Message
		fmt.Printf("Got event: %v\n", eventData)
		fmt.Printf("Timestamp: %f\n", *eventData.Timestamp)
	})
	console.Enable()
	// recv events
	console.Disable()

In the future there are plans to make event handling easier, but for now you'll need to know the event type and unmarshall it yourself. If you are unsure of what events will come in, i've helpfully left in debugging messages saying unable to dispatch event and give the full dump :>. This is alpha code at best so use caution.

Usage

If you need to create complex types, you'll need to import the "github.com/wirepair/gcd/gcdprotogen/types" library. It contains all of the types the chrome remote debugger protocol uses. If you are just accessing them from return values it should not be necessary to import.

For a full list of api methods & godocs: Documentation For a full list of type data: Types Documentation

Loading a page using the Page API.

package main

import (
	"github.com/wirepair/gcd"
	"log"
	"sync"
)

func main() {
	var wg sync.WaitGroup
	wg.Add(1)
	debugger := gcd.NewChromeDebugger()
	// start process, specify a tmp profile path so we get a fresh profiled browser
	// set port 9222 as the debug port
	debugger.StartProcess("C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe", "C:\\tmp\\", "9222")
	defer debugger.ExitProcess() // exit when done
	targets := debugger.GetTargets() // get the 'targets' or tabs/background processes
	target := targets[0] // take the first one

	//subscribe to page load
	target.Subscribe("Page.loadEventFired", func(targ *gcd.ChromeTarget, v []byte) {
		wg.Done() // page loaded, we can exit now
		// if you wanted to inspect the full response data, you could do that here, or unmarshal it 
		// if you know the proper type
	})
	page := target.Page() // get the Page API
	page.Enable() // Enable so we can recv events
	ret, err := page.Navigate("http://www.veracode.com") // navigate
	if err != nil {
		log.Fatalf("Error navigating: %s\n", err)
	}
	log.Printf("ret: %#v\n", ret)
	wg.Wait() // wait for page load
}

Getting a document from a target.

package main

import (
	"github.com/wirepair/gcd"
	"log"
)

func main() {
	debugger := gcd.NewChromeDebugger()
	debugger.StartProcess("C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe", "C:\\tmp\\", "9222")
	defer debugger.ExitProcess()
	targets := debugger.GetTargets()
	target := targets[0]
	dom := target.DOM()
	r, err := dom.GetDocument()
	if err != nil {
		log.Fatalf("error: %s\n", err)
	}

	log.Printf("NodeID: %d Node Name: %s, URL: %s\n", *r.NodeId, r.NodeName, r.DocumentURL)
}

TODO: Moar Examples.

Licensing

The MIT License (MIT)

Copyright (c) 2014 isaac dawson

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.