I am running puppeteer on a Linux VM, which does not have a display; however, I am using xvfb to remedy that.
For some background: The overall goal of this program is to navigate to a page and authenticate using puppeteer. From there, I audit several webpages using Lighthouse.
I have been running this script for several weeks in headless no issues. I've recently found that the performance metrics of the headless Lighthouse runs far better than reality by running manual tests on my local machine through chrome developer tools. If it's relevant, I specifically noticed a huge gap in the number of recorded DOM nodes. Long story short, I now need to run this script in headful mode.
After installing and implementing xvfb in my code, I have been able to start a display within my script without hitting any errors. I used the answer from this question as reference: Running Puppeteer with xfvb headless : false
With all of that out of the way, onto the actual issue: this script, including the xvfb implementation, still runs flawlessly in headless mode with absolutely no timeouts despite repeated runs. When I try running it in headful mode, I consistently timeout on the puppeteer launch, even when I tried extending the timeout to 5 minutes. I've tried an absurd amount of launch-option combinations to no avail. Any and all help would be so greatly appreciated, even if it means significantly altering my approach to the problem. Thank you!
I have a single process node.js application, which I wish to debug with Intellij IDEA 11 32 bits (node.js is 32 bits too).
So, I place an initial breakpoint and run. The debugger stops at the breakpoint, but then it refuses to do any of the following:
step into
go to another breakpoint
pause execution
When I step into, it seems just to run, without stepping through the code. Once running, it ignores any subsequent breakpoints and does not break when I press the pause button.
This issue drives me crazy.
Any ideas on how should I troubleshoot it?
EDIT
More info. After IDEA breaks on the first breakpoint (the only successful time) I try to inspect the variables and am unable to see any. IDEA is stuck on "Collecting data..." The watch window does not work too.
EDIT2
Justed posted an issue to their bug tracking system - http://youtrack.jetbrains.com/issue/IDEA-112925
I've been noticing that IntelliJ's node.js debugger kinda sucks. It's death by 1000 cuts. I love IntelliJ to death, its such a nice IDE. But for node, the debugger has a million different scenarios where breakpoints don't work properly, and another million where it doesn't properly give you access to the in-scope variable values, and another million where it doesn't step properly...
I'm gonna hafta try looking for another tool..
UPDATE 2014-01-13: I've been using IntelliJ's debugger for a while now (having found no other good tool). It seems some of the problems with it are problems with node or v8 itself. Most of the problems I was having have either actually been solved by newer versions of IntelliJ, or by using this workaround:
1. create a file called proxyDebug.js
2. put the following content in it:
require('path/to/the/script/you/want/to/debug.js')
3. point your debugger to that file
Apparently the node.js debugging hooks go buggy at the entrypoint script, so by creating this proxy entrypoint that we don't care at all about, there won't be any weird bugs caused by that in the scripts you do care about. The bugs this workaround fixed were missed breakpoints, predefined variables (exports, module, process, etc) being inaccessible by the debugger, and one or two other things I can't remember.
Last WebStorm version I tried (7.0.3) actually takes ages in collecting data but eventually works. If it seems stuck to you, try to leave it for a minute
My company has built up a wonderful large (472 and growing) Mocha test suite for our app, and it's incredibly useful ... in Chrome and Firefox.
In IE however the tests break down after 30 or so tests, with an "Error: Out of stack space". So, my question is ... well really I have two questions, the main one and a back-up:
1) is there any way to just get IE to run the whole suite, perhaps by tweaking some config option somewhere to give it more memory? I know IE generally sucks at this sort of thing, but if Firefox and Chrome can do it I have to hope there's some way to make IE do it too ...
2) failing that, is there a good way in Mocha to say "run tests 1-25, now run tests 26-50, etc.", or do I just have to use the grep option to try an limit the number of tests run?
Guess I should have spent a bit more time Googling before I came here. I eventually found this ticket:
https://github.com/visionmedia/mocha/issues/502
Which explains that:
this is basically bug in Mocha: they're using some sort of mechanism to clear the stack, but that mechanism doesn't work in IE so they need to switch to some other mechanism (and haven't yet, as of 4/25/2013).
a (very dirty/hacky, but functional) workaround is to add the following beforeEach at the root level of your test suite (so that it applies to all tests):
beforeEach(function(done){
window.setTimeout(done, 0);
});
I'm going to write bunch of browser extensions (the same functionality for each popular browser). I hope, that some of the code will be shared, but I'm not sure about this yet. For sure some of extensions will use native API. I have not much experience with TDD/BDD, and I thought it's good time to start folowing these ideas from this project.
The problem is, I have no idea how to handle it. Should I write different tests for each browser? How far should I go with these tests? These extensions will be quite simple - some data in a local storage, refreshing a page and listening through web sockets.
And my observation about why is it hard for me - because there is a lot of behaviour, and not so much models, which are also dependent on a platform.
I practise two different ways of testing my browser extensions:
Unit tests
Integration test
Introduction
I will use the cross-browser YouTube Lyrics by Rob W extension as an example throughout this answer. The core of this extension is written in JavaScript and organized with AMD modules. A build script generates the extension files for each browser. With r.js, I streamline the inclusion of browser-specific modules, such as the one for cross-origin HTTP requests and persistent storage (for preferences), and a module with tons of polyfills for IE.
The extension inserts a panel with lyrics for the currently played song on YouTube, Grooveshark and Spotify. I have no control over these third-party sites, so I need an automated way to verify that the extension still works well.
Workflow
During development:
Implement / edit feature, and write a unit test if the feature is not trivial.
Run all unit tests to see if anything broke. If anything is wrong, go back to 1.
Commit to git.
Before release:
Run all unit tests to verify that the individual modules is still working.
Run all integration tests to verify that the extension as whole is still working.
Bump versions, build extensions.
Upload update to the official extension galleries and my website (Safari and IE extensions have to be hosted by yourself) and commit to git.
Unit testing
I use mocha + expect.js to write tests. I don't test every method for each module, just the ones that matter. For instance:
The DOM parsing method. Most DOM parsing methods in the wild (including jQuery) are flawed: Any external resources are loaded and JavaScript is executed.
I verify that the DOM parsing method correctly parses DOM without negative side effects.
The preference module: I verify that data can be saved and returned.
My extension fetches lyrics from external sources. These sources are defined in separate modules. These definitions are recognized and used by the InfoProvider module, which takes a query, (black box), and outputs the search results.
First I test whether the InfoProvider module functions correctly.
Then, for each of the 17 sources, I pass a pre-defined query to the source (with InfoProvider) and verify that the results are expected:
The query succeeds
The returned song title matches (by applying a word similarity algorithm)
The length of the returned lyrics fall inside the expected range.
Whether the UI is not obviously broken, e.g. by clicking on the Close button.
These tests can be run directly from a local server, or within a browser extension. The advantage of the local server is that you can edit the test and refresh the browser to see the results. If all of these tests pass, I run the tests from the browser extension.
By passing an extra parameter debug to my build script, the unit tests are bundled with my extension.
Running the tests within a web page is not sufficient, because the extension's environment may differ from the normal page. For instance, in an Opera 12 extension, there's no global location object.
Remark: I don't include the tests in the release build. Most users don't take the efforts to report and investigate bugs, they will just give a low rating and say something like "Doesn't work". Make sure that your extension functions without obvious bugs before shipping it.
Summary
View modules as black boxes. You don't care what's inside, as long as the output matches is expected or a given input.
Start with testing the critical parts of your extension.
Make sure that the tests can be build and run easily, possibly in a non-extension environment.
Don't forget to run the tests within the extension's execution context, to ensure that there's no constraint or unexpected condition inside the extension's context which break your code.
Integration testing
I use Selenium 2 to test whether my extension still works on YouTube, Grooveshark (3x) and Spotify.
Initially, I just used the Selenium IDE to record tests and see if it worked. That went well, until I needed more flexibility: I wanted to conditionally run a test depending on whether the test account was logged in or not. That's not possible with the default Selenium IDE (it's said to be possible with the FlowControl plugin - I haven't tried).
The Selenium IDE offers an option to export the existing tests in other formats, including JUnit 4 tests (Java). Unfortunately, this result wasn't satisfying. Many commands were not recognized.
So, I abandoned the Selenium IDE, and switched to Selenium.
Note that when you search for "Selenium", you will find information about Selenium RC (Selenium 1) and Selenium WebDriver (Selenium 2). The first is the old and deprecated, the latter (Selenium WebDriver) should be used for new projects.
Once you discovered how the documentation works, it's quite easy to use.
I prefer the documentation at the project page, because it's generally concise (the wiki) and complete (the Java docs).
If you want to get started quickly, read the Getting Started wiki page. If you've got spare time, look through the documentation at SeleniumHQ, in particular the Selenium WebDriver and WebDriver: Advanced Usage.
Selenium Grid is also worth reading. This feature allows you to distribute tests across different (virtual) machines. Great if you want to test your extension in IE8, 9 and 10, simultaneously (to run multiple versions of Internet Explorer, you need virtualization).
Automating tests is nice. What's more nice? Automating installation of extensions!
The ChromeDriver and FirefoxDriver support the installation of extensions, as seen in this example.
For the SafariDriver, I've written two classes to install a custom Safari extension. I've published it and sent in a PR to Selenium, so it might be available to everyone in the future: https://github.com/SeleniumHQ/selenium/pull/87
The OperaDriver does not support installation of custom extensions (technically, it should be possible though).
Note that with the advent of Chromium-powered Opera, the old OperaDriver doesn't work any more.
There's an Internet Explorer Driver, and this one does definitely not allow one to install a custom extension. Internet Explorer doesn't have built-in support for extensions. Extensions are installed through MSI or EXE installers, which are not even integrated in Internet Explorer. So, in order to automatically install your extension in IE, you need to be able to silently run an installer which installs your IE plugin. I haven't tried this yet.
Testing browser extensions posed some difficulty for me as well, but I've settled on implementing tests in a few different areas that I can invoke simultaneously from browsers driven by Selenium.
The steps I use are:
First, I write test code integrated into the extension code that can be activated by simply going to a specific URL. When the extension sees that URL, it begins running the tests.
Then, in the page that activates the testing in the extension I execute server-side tests to be sure the API performs, and record and log issues there. I record the methods invoked, the time they took, and any errors. So I can see the method the extension invoked, the web performance, the business logic performance, and the database performance.
Lastly, I automatically invoke browsers to point at that specific URL and record their performance along with other test information, errors, etc on any given client system using Selenium:
http://docs.seleniumhq.org/
This way I can break down the tests in terms of browser, extension, server, application, and database and link them all together according to specific test sets. It takes a bit of work to put it all together, but once its done you can have a very nice extension testing framework.
Typically for cross-browser extension development in order to maintain a single code-base I use crossrider, but you can do this with any framework or with native extensions as you wish, Selenium won't care, it is just driving the extension to a particular page and allowing you to interact and perform tests.
One nice thing about this approach is you can use it for live users as well. If you are providing support for your extension, have a user go to your test url and immediately you will see the extension and server-side performance. You won't get the Selenium tests of course, but you will capture a lot of issues this way - very useful when you are coding against a variety of browsers and browser versions.
I'm trying to make some tests on a JavaScript application and someone advised me to use Selenium. I visited its site but I cannot understand what is it and how can I use it for testing. Can someone help me understand?
There are a lot of options and it can be quite daunting to start.
Start with the IDE. It is a Firefox plug-in and would get you writing tests in no time. This is good for semi-automated tests running only on Firefox. And good to get some scripts generated for you to kick-start your tests.
Setup RC. It is a Java program that runs on 'a' box (could be localhost) spawning browsers and running your tests and you can connect to it using variety of languages and program your tests. RC is your friend if you want to automate your testing completely.
As for Grid, it is yet another Java program that manages different RCs on your network which makes it all distributed from browser, load and functionality perspectives. You don't need this initially and when the time comes your work on RC would be reusable 80-100%.
If you're using the Firefox plugin, all you have to do is record a "test". Then generate the testing code in the language you want to run the scripts in. They have an option for Java - and the test can be run standalone (outside of a browser on any platform). The test will attempt to replicate what you did in the browser. If it is able to complete the same steps, your test passes.
Selenium replicates what the browser does when running it's tests and does an admirable job (though not perfect)