/gempesaw/writing

Browsermob Proxy is an open source project that Patrick Lightbody split off from the main Selenium project. It works really well in tandem with Selenium Webdriver, but it was missing Perl bindings. BMP exposes a RESTish interface for interacting with the proxies, so I've strung together a Perl module to take care of it: Browsermob::Proxy. Amongst other things, you can use BMP to throttle net traffic during tests, analyze request/response pairs for things like Omniture and Google Analytics, and even alter the requests on the fly with custom headers. Here's a short run down and some basic get-started scripts for using it!

The bindings are up on CPAN with pretty limited functionality at the moment - definitely not the full BMP API. It can create proxies and HARs, and spit out the HARs back out when requested, but it doesn't do much else besides that as of v0.04. To get up and running with BMP, you'll need to download the binary from the BMP website and then execute the appropriate file in its bin/ folder to start the BMP server.

Here's an example of using Browsermob::Proxy with Selenium::Remote::Driver to capture all of the network traffic during a single request to google:

#! /usr/bin/perl

use strict;
use warnings;
use DDP;
use Browsermob::Proxy;
use Selenium::Remote::Driver;

my $proxy = Browsermob::Proxy->new(
    server_port => 8080,
);

my $driver = Selenium::Remote::Driver->new(
    browser_name => 'chrome',
    proxy        => $proxy->selenium_proxy
);

$driver->get('https://www.google.com');

p $proxy->har;

This is assuming your BMP server is already downloaded and currently running on port 8080. But, that's all we need to create a new proxy for the Chrome browser that Selenium::Remote::Driver is about to make. The $proxy comes with a convenience method selenium_proxy() that returns the appropriate desired capabilities to configure the proxy for use with Chrome. (If you want to use a proxy with Firefox, you'll need to use a custom Firefox profile.)

Once we've instantiated our driver, having told it to use the proxy, all that's left is to create some traffic and spit out the HAR.

If you want to try out the module without having to install Selenium::Remote::Driver, you can just curl some traffic across the proxy:

#! /usr/bin/perl

use strict;
use warnings;
use DDP;
use Browsermob::Proxy;

my $proxy = Browsermob::Proxy->new(
    server_port => 8080,
);

$proxy->new_har;
my $generate_traffic = 'curl -x http://127.0.0.1:' . $proxy->port
    . ' http://www.google.com > /dev/null 2>&1';

`$generate_traffic`;
p $proxy->har;

This creates a proxy in exactly the same fashion and then uses curl to generate the traffic.