CAPTCHA, short for Completely Automated Public Turing test to tell Computers and Humans Apart, are explicitly designed to prevent automations, so don't try! There are two primary strategies to get around CAPTCHA checks:
- Disable CAPTCHAs in your test environments
- Add a hook to allow tests to bypass the CAPTCHA
For some browser configurations in Selenium RC, Selenium acted as a
proxy between the browser and the site being automated. This meant
that all browser traffic passed through Selenium, and could be
captured or manipulated. The captureNetworkTraffic() method
purported to capture all of the network traffic between the browser
and the site being automated, including HTTP response codes.
Selenium WebDriver is a completely different approach to browser automation, preferring to act more like a user and this is represented in the way you write tests with WebDriver. In automated functional testing, checking the status code is not a particularly important detail of a test's failure; the steps that preceded it are more important.
The browser will always represent the HTTP status code, imagine for
example a 404 or a 500 error page. A simple way to “fail fast” when
you encounter one of these error pages is to check the page title or
content of a reliable point (e.g. the <h1> tag) after every page
load. If you are using the page object model you can include this
check in your class constructor or similar point where the page load
is expected. Occasionally the HTTP code may even be represented in
the browser's error page and you could use WebDriver to read this and
improve your debugging output.
Checking the webpage itself is inline with WebDriver's ideal practice of representing and asserting upon the user's view of the website.
If you insist, an advanced solution to capturing HTTP status codes is to replicate the behavior of Selenium RC by using a proxy. WebDriver API provides the ability to set a proxy for the browser, and there are a number of proxies that programmatically allow you to manipulate the contents of requests sent to and received from the web server. Using a proxy lets you decide how you want to respond to redirection response codes. Additionally, not every browser makes the response codes available to WebDriver, so opting to use a proxy allows you to have a solution that works for every browser.
For multiple reasons logging into sites like Gmail and Facebook using WebDriver is not recommended. Aside from being against the usage terms for these sites (where you risk having the account shut down), it is slow and unreliable. Not what we want where test stability is important.
The ideal practice is to use the APIs that email providers offer, or in the case of facebook the developer tools service which exposes an API for creating test accounts, friends and so forth. Although using an API might seem like a bit extra hard work you will be paid back in speed, reliabilty and stability. The API is also unlikely to change whereas webpages and HTML locators change often and require you to update your test framework.
Logging in to 3rd-party sites using WebDriver at any point of your test increases the risk of your test failing because it makes your test longer. A general rule of thumb is that longer tests are more fragile and unreliable.
Performance testing using Selenium and WebDriver is generally not advised. Not because it is incapable but because it is not optimised for the job and this you are unlikely to get good results.
It may seem ideal to performance test in the context of the user but a suite of WebDriver tests are subjected to lots of points of external fragility which is beyond your control; for example Browser startup speed, speed of HTTP servers, response of 3rd party servers that host Javascript or CSS. Variation at these points will cause variation in your results. It is very difficult to separate the difference between the performance of your website and the performance of external resources. As WebDriver is only an API you will need to develop this reporting yourself.
The other potential attraction is 'saving time' - performing functional and performance tests at the same time. However functional and performance tests have opposing objectives. To test functionality a test may need to be patient and wait for loading but this will cloud the performance testing results and vice versa.
To improve the performance of your website you will need to be able to analyse overall performance independent of environment differences, identify poor code practices, breakdown of performance of individual resources (ie css or javascript) in order to know what to improve. There are performance testing tools available that can do this job, provide reporting and analysis and even make improvement suggestions.
Example (open source) packages to use are: Jmeter ?