Protractor Max Call Stack Error - selenium

I've been using Protractor for quite awhile now and am familiar with a range of errors related to Protractor, Webdriver, Jasmine etc. Recently, I've encountered one I haven't seen before:
A Jasmine spec timed out. Resetting the WebDriver Control Flow.
/usr/local/lib/node_modules/protractor/node_modules/selenium-webdriver/lib/promise.js:714
super(opt_msg);
^
RangeError: Maximum call stack size exceeded
While I have seen maximum call stack errors before, they are typically related to recursive functions or ridiculously large for loops.
So I am a little lost on what this means for Protractor/Webdriver. Per my understanding, this is a browser-related error. But I don't have much JavaScript going directly to the browser (just some forced clicks, and logging a few objects).
Also, I have only seen this error while running my entire suite of tests (~500 specs), but it does not happen every time and it also does not occur in the same spot which concerns me... it's a flaky error.
Does anyone have an explanation for this error?

One of the reasons Maximum call stack size exceeded error occurs is when a function calls itself. For example
let next = async function () {
await $nextButton.click();
await next(); // function calls itself here
}
What happens here is the code gets in an infinite loop and throws the error
Thus just go over your code and make sure you don't do it somewhere by accident

Related

How do I troubleshoot this api call?

I have the following code...
async function GetFirstAssessment() {
try {
const response = await axios.get('http://192.168.254.10/App/GetFirstAssessment/');
return response.data;
} catch (error) {
alert('error: ' + error);
console.error(error);
}
};
It's been working fine for some time, but suddenly it no longer works and eventually times out. Or I don't even know if it "times out" since I believe the default timeout for axios is 0 but eventually it does error with the message "Error: Network Error". I've also added a picture of the stack trace but I don't think it's helpful.
I can put the url in a browser and it returns the json I'm expecting, so the problem is definitely not on the server side. I am testing from an android device connected via usb and developing with cli (not expo).
If there is any other information I can provide please let me know... not sure what to do next because this really makes no sense. I would wonder if it was a security issue except that it was working perfectly earlier. Also I have updated some other code that calls this, but even after reverting I still have the same problem... and seeing as how it is making it to the catch, I don't see how any other code could be affecting this.
I did just install the standalone react native debugger. I believe it has worked since I installed it, though I'm not 100% certain on that. Still doesn't work after closing it.
I set a break point in the server code on the first line of the api method, but it doesn't get hit. Not sure how to troubleshoot further up the chain though. I also just thought to check fiddler and it doesn't show any request coming in, though I honestly don't know if it should normally or not.

What is SetScriptTimeout-Webdriver

when SetScriptTimeout should be used and please provide me any example.
I know the defn
Sets the amount of time to wait for an asynchronous script to finish execution before throwing an error. If the timeout is negative, then the script will be allowed to run indefinitely.
but not sure what it does exactly.
You've got two answers already, neither of which I find explain clearly the point of setting a script timeout.
First, it is important the script timeout affects only JavaScript code executed with executeAsyncScript and nothing else. In particular, executeScript is not affected by it.
So why do you want to set a timeout for executeAsyncScript? Chandan Nayak correctly explained that the default timeout is 0s so you have to change this timeout if you want to use executeAsyncScript with asynchronous scripts that actually perform some work. But why not just set it to -1 and be done with it? After all, if you set it to -1 then you turn off the timeout. So you won't get any timeouts anymore. Mission accomplished, right? Nope.
What you want to do is set the timeout to a value that allows the code you use with executeAsyncScript to perform it works while at the same time detect when a script has gone rogue. For instance, if from experience you know that a script you pass to executeAsyncScript is going to be done in 2 seconds or less (except perhaps in extremely unusual circumstances), then you set the timeout to 2 seconds so that if there is a bug somewhere and the code never terminates, you get a timeout after 2 seconds. Otherwise, Selenium will happily wait forever for the script to complete.
From WebDriver documentation:
setScriptTimeout(long time, java.util.concurrent.TimeUnit unit)
Sets the amount of time to wait for an asynchronous script to finish execution before throwing an error. This works only for Assync scripts (executeAsyncScript)
Let's run a simple javascript: (Do not set setScriptTimeout ) - Now this shall execute without throwing any issue.
((JavascriptExecutor) driver).executeScript("alert('hello world');");
Lets run a simple Assync Script: ( Do not set setScriptTimeout) - This shall fail with error - "Timed out waiting for async script result after 0ms"
((JavascriptExecutor) driver).executeAsyncScript("window.setTimeout(arguments[arguments.length - 1], 500);");
To resolve the issue: setScriptTimeout to 1 Second:
driver.manage().timeouts().setScriptTimeout(1, TimeUnit.SECONDS);
And then run the same Assync Script mentioned above and it shall execute without any error.
Reason:
The default timeout for a script to be executed is 0ms. In most cases, including the examples below, one must set the script timeout WebDriver.Timeouts.setScriptTimeout(long, java.util.concurrent.TimeUnit) beforehand to a value sufficiently large enough
More Reference Links:
When should setScriptTimeout be used?
WebDriver executeAsyncScript vs executeScript
WebDriver Doc
Web application automation is dependent on many factors like browser, network speed, embedded scripting etc. To write robust code for running in all environments we need to inserts wait for WebElements before performing any operation on that.
WebDriver wait (synchronization) can be obtained either by using support.ui or driver().manage().timeouts()
If we use driver.manage().timeouts(), a common practice to achieve synchronization is to use JavaScript via JavascriptExecutor which in turn provide two methods for script execution:
executeAsyncScript -> This method doesn't block the execution of next line of code...till execution of this method is completed. This method will execute as well as next line of code will be executed...asynchronously. (without blocking each other)
executeScript -> This method will block the execution till it's execution is completed and then it moves to next line of code. In short your automation code will halt till the Javascript is executed via this method.
Now since executeAsyncScript method doesn't block the execution of next line of code, it might be beneficial to use driver.manage().timeouts().setScriptTimeout(30,SECONDS);
so that our code can wait for specified amount of time for an asynchronous script to finish execution before throwing an error.

PhantomJs Crashes while running with grunt-karma test cases ????/

We are facing an issue while running karma test cases with phantomJs our phantomJs crashes and gets disconnected.
Is that due to memory leakage or some other issue.Kindly let me know if some one has some suitable solution.
I found that the workaround is to break test cases into multiple grunt task but since we have a lot of test cases more than 1500 so that would not be a feasible task.
We are using the below versions
Node:- 0.10.32
Karma:- 0.12.24
PhantomJs:- 1.9.8 (karma-phantomJs-Launcher)
Please let me know the solutions asap.
There are two reasons I found that this can happen.
PhantomJS does not release memory until its tab is closed so if your test suite is too large, you could be running out of memory.
karma-phantomjs-launcher & karma-phantomjs2-launcher do not hook the stdout/stderr output for their started browser process and so I've seen some instances that the started browser just hangs and gets disconnected, most likely due to its stderr output getting filled up
The first problem can be worked around by splitting your test suite into smaller ones. Or, you could research if there is perhaps a way to tell PhantomJS to run its JavaScript garbage collection, but I have not gone down that road so can't provide much more detail there.
The second problem can be fixed by:
using the latest karma-phantomjs-launcher version that hooks browser the stdout/stderr output (fixed in version 0.2.1)
using a version of karma-phantomjs2-launcher from its pull request #5 which brings in upstream changes from the base karma-phantomJS-launcher project and thus resolves the problem here as well.
I had the same kind of issue with handling random crashes. Though i did not find a way to avoid them, there is the possibility to restart the grunt-task upon a crash.
grunt.registerTask('karma-with-retry', function (opt) {
var done = this.async();
var count = 0;
var retry = function () {
grunt.util.spawn({
cmd : "grunt",
args : ["connect", "karma"], // your tasks
opts: {
stdio: 'inherit'
}
}, function (error, result, code) {
count++;
if (error && code === 90 /* Replace with code thrown by karma */) {
if(count < 5) {
grunt.log.writeln("Retrying karma tests upon error: " + code );
retry();
} else {
done(false);
}
} else {
done(result);
}
});
}
retry();
});
Source https://github.com/ariya/phantomjs/issues/12325#issuecomment-56246505
I was getting Phantom crashed when asserting the following line
dom.should.be.instanceof(HTMLCollection);
Worked on chrome, but phantom was crashing without any useful error message.
I've been able to see the real error message after running the same test on PhantomJS_debug browser with debug option set to true.
The following error message started showing up.
The instanceof assertion needs a constructor but object was given.
Instead of
PhantomJS has crashed. Please read the bug reporting guide at
<http://phantomjs.org/bug-reporting.html> and file a bug report.
So chrome was ok with the assertion but phantom 2.1.1 is crashing with the above error. Hope this will help.

python - HTTP Error 503 Service Unavailable

I am trying to scrape data from google and linkedin. Somehow it gave me this error:
*** httperror_seek_wrapper: HTTP Error 503: Service Unavailable
Can someone help advice how I solve this?
Google is simply detecting your query as automated. You would need a captcha solver to get unlimited results. The following link might be helpful.
https://support.google.com/websearch/answer/86640?hl=en
Bypassing Captcha using an OCR Engine:
http://www.debasish.in/2012/01/bypass-captcha-using-python-and.html
Simple Approach:
An even simpler approach is to simply use sleep() a few times and to generate random queries. This way google will not spot that you are using an automated system. But the system is far slower ...
Error Handling:
To simply get remove the error message use try and except
I encountered the same situation and tried using the sleep() function before every request to spread the requests a little. It looked like it was working fine but failed soon enough even with a delay of 2 seconds. What solved it finally was using:
with contextlib.closing(urllib.urlopen(urlToOpen)) as x:
#do stuff with x.
This I did because I thought opening too many requests keeps it open and had to closed. Nevertheless, it worked quite consistently with as less as 0.5s delay time.

Preventing Exceptions without Stack Frames with Error Exception Handler and Shutdown Sequences

I've run over a somewhat little problem over the week. The error message upfront this is about:
[30-Dec-2012 15:19:32] PHP Fatal error: Exception thrown without a stack frame in Unknown on line 0
I think it is because my error handler (see below for details) is turning any error into an exception. I might should prevent that in case there is no stack frame.
Is there an easy way to find out if there is any stack frame or not in PHP?
Details:
On one of my websites I've got an error handler running that is turning every error into an exception, the common ErrorException to be precise.
I introduced it some time ago because the site is mainly legacy code and I wanted to have any issue result in an exception I can finally "catch" in a streamlined fashion an exception handler and give the request a stop.
I put this into class of it's own, the handler is registered and also in parallel an output buffer is opened to catch the output up until the exception is thrown. Basically code like this:
// register output buffering
$r = ob_start(array($this, 'handleBuffer'));
// register error handler
$this->_originalErrorHandler = set_error_handler(array($this, 'handleError'));
// register exception handler
$this->_originalExceptionHandler = set_exception_handler(array($this, 'handleException'));
This worked all fine and dandy until I decided to add another output buffering class into the mix. Just one that catches as well all output and then can do some "post production" on the website, including checking for HTML problems (yes, it's all a bit legacy so actually this is a bit duck-taped, I know). That also worked very fine btw. however not when I made a mistake in the new component:
[30-Dec-2012 15:19:32] PHP Fatal error: Exception thrown without a stack frame in Unknown on line 0
This is basically my problem. Is there an easy way to prevent getting these errors? I somewhat know why the error is given but I'm not so entirely sure so it's hard for me to really circumvent the problem. I tried to release the new output buffer before the script enters the new shutdown phase because I thought this would cause this. But this didn't make it.
Your problem indicates that you are using an EOL (End Of Life) version of PHP (specifically PHP < 5.3.0), which means it's no longer supported. This issue comes from throwing an exception where no strack frame exists and as such the old engine did not know how to handle those exceptions properly.
This can be due to a couple of different reasons. Some of the most common ones are as follows:
You threw an exception from inside an error handler or exception handler.
You threw an exception from inside a destructor.
You threw an exception from inside a callback (like an output buffering callback function).
Here's an example that demonstrates your problem under some of those circumstances...
function myErrorHandler($errno, $errstr, $errfile, $errline)
{
throw new ErrorException($errstr, $errno, 0, $errfile, $errline);
}
function myExceptionHandler($exception) {
echo "We got an exception with message: '{$exception->getMessage()}'";
}
function myCallBack($contents) {
trigger_error('ohnoes!'); // You can't throw an error from the output buffer callback function in older versions of PHP < 5.3
}
class Foo {
public function __destruct() {
trigger_error('ohnoes!'); // You can't throw an error from a destructor in older versions of PHP < 5.3
}
}
set_error_handler('myErrorHandler');
set_exception_handler('myExceptionHandler');
The above code would cause you to see the fatal error you described here...
ob_start("myCallBack");
... and here...
$foo = new foo;
This problem has been fixed in PHP >= 5.3.0 so you should not see this issue if you were using the most current version of PHP.
The simplest fix is to upgrade your PHP. If that is not an option you must consider these facts that you can not throw exceptions where PHP does not expect them to be thrown (in callback functions, error handlers, exceptions handlers, etc... -- which are actually all considered to be callbacks to PHP).
The other thing is you should not be turning every error into an exception in this way. If what you are doing is as the code I supplied demonstrates (i.e. throwing an exception from inside the error handler -- thus turning every error into an exception) then you are going to cause yourself a lot of pain and with virtually no benefit. PHP errors are not meant to be handled. They are meant to inform the client of a problem (the client being the person writing the PHP code), or potential problem. Handling the error itself is not as simple as turning every error into an exception and then handling that exception, because not every error should be exceptional. For instance, E_NOTICE level errors have no place in exception handling. They are primarily used to notify you of a potential for a bug, not that there is necessarily something buggy with your code and not to mention that most of them can't even be handled easily in user-space code (they mostly require re-factoring the code itself). I strongly advice against this poor practice.