PHP Scriptable Web Browser
SimpleTest's web browser component can be used not just
outside of the WebTestCase
class, but also
independently of the SimpleTest framework itself.
The Scriptable Browser
You can use the web browser in PHP scripts to confirm services are up and running, or to extract information from them at a regular basis. For example, here is a small script to extract the current number of open PHP 5 bugs from the PHP web site...
<?php require_once('simpletest/browser.php'); $browser = &new SimpleBrowser(); $browser->get('http://php.net/'); $browser->click('reporting bugs'); $browser->click('statistics'); $page = $browser->click('PHP 5 bugs only'); preg_match('/status=Open.*?by=Any.*?(\d+)<\/a>/', $page, $matches); print $matches[1]; ?>There are simpler methods to do this particular example in PHP of course. For example you can just use the PHP
file()
command against what here is a pretty fixed page.
However, using the web browser for scripts allows authentication,
correct handling of cookies, automatic loading of frames, redirects,
form submission and the ability to examine the page headers.
Such methods are fragile against a site that is constantly
evolving and you would want a more direct way of accessing
data in a permanent set up, but for simple tasks this can provide
a very rapid solution.
All of the navigation methods used in the
WebTestCase
are present in the SimpleBrowser
class, but
the assertions are replaced with simpler accessors.
Here is a full list of the page navigation methods...
addHeader($header) | Adds a header to every fetch |
useProxy($proxy, $username, $password) | Use this proxy from now on |
head($url, $parameters) | Perform a HEAD request |
get($url, $parameters) | Fetch a page with GET |
post($url, $parameters) | Fetch a page with POST |
clickLink($label) | Follows a link by label |
clickLinkById($id) | Follows a link by attribute |
getUrl() | Current URL of page or frame |
getTitle() | Page title |
getContent() | Raw page or frame |
getContentAsText() | HTML removed except for alt text |
retry() | Repeat the last request |
back() | Use the browser back button |
forward() | Use the browser forward button |
authenticate($username, $password) | Retry page or frame after a 401 response |
restart($date) | Restarts the browser for a new session |
ageCookies($interval) | Ages the cookies by the specified time |
setCookie($name, $value) | Sets an additional cookie |
getCookieValue($host, $path, $name) | Reads the most specific cookie |
getCurrentCookieValue($name) | Reads cookie for the current context |
SimpleBrowser::useProxy()
and
SimpleBrowser::addHeader()
are special.
Once called they continue to apply to all subsequent fetches.
Navigating forms is similar to the WebTestCase form navigation...
setField($name, $value) | Sets all form fields with that name |
setFieldById($id, $value) | Sets all form fields with that id |
getField($name) | Accessor for a form element value |
getFieldById($id) | Accessor for a form element value |
clickSubmit($label) | Submits form by button label |
clickSubmitByName($name) | Submits form by button attribute |
clickSubmitById($id) | Submits form by button attribute |
clickImage($label, $x, $y) | Clicks an input tag of type image by title or alt text |
clickImageByName($name, $x, $y) | Clicks an input tag of type image by name |
clickImageById($id, $x, $y) | Clicks an input tag of type image by ID attribute |
submitFormById($id) | Submits by the form tag attribute |
Within a page, individual frames can be selected. If no selection is made then all the frames are merged together in one large conceptual page. The content of the current page will be a concatenation of all of the frames in the order that they were specified in the "frameset" tags.
getFrames() | A dump of the current frame structure |
getFrameFocus() | Current frame label or index |
setFrameFocusByIndex($choice) | Select a frame numbered from 1 |
setFrameFocus($name) | Select frame by label |
clearFrameFocus() | Treat all the frames as a single page |
What went wrong?
All of this functionality is great when we actually manage to fetch pages, but that doesn't always happen. To help figure out what went wrong, the browser has some methods to aid in debugging...
setConnectionTimeout($timeout) | Close the socket on overrun |
getRequest() | Raw request header of page or frame |
getHeaders() | Raw response header of page or frame |
getTransportError() | Any socket level errors in the last fetch |
getResponseCode() | HTTP response of page or frame |
getMimeType() | Mime type of page or frame |
getAuthentication() | Authentication type in 401 challenge header |
getRealm() | Authentication realm in 401 challenge header |
setMaximumRedirects($max) | Number of redirects before page is loaded anyway |
setMaximumNestedFrames($max) | Protection against recursive framesets |
ignoreFrames() | Disables frames support |
useFrames() | Enables frames support |
ignoreCookies() | Disables sending and receiving of cookies |
useCookies() | Enables cookie support |
SimpleBrowser::setConnectionTimeout()
SimpleBrowser::setMaximumRedirects()
,
SimpleBrowser::setMaximumNestedFrames()
,
SimpleBrowser::ignoreFrames()
,
SimpleBrowser::useFrames()
,
SimpleBrowser::ignoreCookies()
and
SimpleBrowser::useCokies()
continue to apply
to every subsequent request.
The other methods are frames aware.
This means that if you have an individual frame that is not
loading, navigate to it using SimpleBrowser::setFrameFocus()
and you can then use SimpleBrowser::getRequest()
, etc to
see what happened.
Complex unit tests with multiple browsers
Anything that could be done in a WebTestCase can now be done in a UnitTestCase. This means that we can freely mix domain object testing with the web interface...
class TestOfRegistration extends UnitTestCase { function testNewUserAddedToAuthenticator() { $browser = &new SimpleBrowser(); $browser->get('http://my-site.com/register.php'); $browser->setField('email', 'me@here'); $browser->setField('password', 'Secret'); $browser->click('Register'); $authenticator = &new Authenticator(); $member = &$authenticator->findByEmail('me@here'); $this->assertEqual($member->getPassword(), 'Secret'); } }While this may be a useful temporary expediency, I am not a fan of this type of testing. The testing has cut across application layers, make it twice as likely it will need refactoring when the code changes.
A more useful case of where using the browser directly can be helpful
is where the WebTestCase
cannot cope.
An example is where two browsers are needed at the same time.
For example, say we want to disallow multiple simultaneous usage of a site with the same username. This test case will do the job...
class TestOfSecurity extends UnitTestCase { function testNoMultipleLoginsFromSameUser() { $first = &new SimpleBrowser(); $first->get('http://my-site.com/login.php'); $first->setField('name', 'Me'); $first->setField('password', 'Secret'); $first->click('Enter'); $this->assertEqual($first->getTitle(), 'Welcome'); $second = &new SimpleBrowser(); $second->get('http://my-site.com/login.php'); $second->setField('name', 'Me'); $second->setField('password', 'Secret'); $second->click('Enter'); $this->assertEqual($second->getTitle(), 'Access Denied'); } }You can also use the
SimpleBrowser
class
directly when you want to write test cases using a different
test tool than SimpleTest.