Cypress tests failing in firefox in pages with polling requests - firefox

I have a following test in Cypress:
visit first page with the header A
click on the Go to B Page button
assert that the header of the page is now B
It works fine in Chrome, but failing in Firefox, as on the page B I have some background polling requests, and when cypress switches to another test and those requests get "canceled" away, I get either TypeError: NetworkError when attempting to fetch resource or AbortError: The operation was aborted
All the requests are using fetch api, by the way.
The possibility to mute those errors through the uncaught:exception event seems a bad idea, and so does the idea to do something on the page to cancel the polling, as it is not the thing under testing.
Maybe someone has encoutnered this problem too and got some non-hacky solution?

I had a similar issue with Cypress tests in Firefox and resorted to the slightly hacky solution of using an uncaught:exception handler as you mention. It is possible to filter error messages somewhat at least:
function handleUncaughtException(err){
if (err.message.includes('Request aborted') ) {
console.log("Request aborted. Test will continue. Error:",err);
return false; // return false to make test continue
}
throw err;
}
cy.on('uncaught:exception',handleUncaughtException);
In principle you can cancel this handler when it's no longer needed. In my case though, this stopped the test working, presumably because the request started previous to or after the calls.
cy.removeListener("uncaught:exception", handleUncaughtException)
The Cypress docs have some advice on defining these: see at https://docs.cypress.io/api/events/catalog-of-events#Examples. It may be useful to put the handler in a support file, so that it is applied to all tests.
(See also https://docs.cypress.io/api/events/catalog-of-events#Event-Types and https://nodejs.org/api/events.html#events_emitter_removelistener_eventname_listener).

Related

How to fix 'Unchecked runtime.lastError: The message port closed before a response was received' chrome issue?

Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
I'm using VueJS and Laravel for my project. This issue started to show lately and it shows even in the old git branches.
This error only shows in the Chrome browser.
I disabled all installed extensions in Chrome - works for me.
I have now clear console without errors.
In case you're an extension developer who googled your way here trying to stop causing this error:
The issue isn't CORB (as another answer here states) as blocked CORs manifest as warnings like -
Cross-Origin Read Blocking (CORB) blocked cross-origin response
https://www.example.com/example.html with MIME type text/html. See
https://www.chromestatus.com/feature/5629709824032768 for more
details.
The issue is most likely a mishandled async response to runtime.sendMessage. As MDN says:
To send an asynchronous response, there are two options:
return true from the event listener. This keeps the sendResponse
function valid after the listener returns, so you can call it later.
return a Promise from the event listener, and resolve
when you have the response (or reject it in case of an error).
When you send an async response but fail to use either of these mechanisms, the supplied sendResponse argument to sendMessage goes out of scope and the result is exactly as the error message says: your message port (the message-passing apparatus) is closed before the response was received.
Webextension-polyfill authors have already written about it in June 2018.
So bottom line, if you see your extension causing these errors - inspect closely all your onMessage listeners. Some of them probably need to start returning promises (marking them as async should be enough). [Thanks #vdegenne]
If you go to chrome://extensions/, you can just toggle each extension one at a time and see which one is actually triggering the issue.
Once you toggle the extension off, refresh the page where you are seeing the error and wiggle the mouse around, or click. Mouse actions are the things that are throwing errors.
So I was able to pinpoint which extension was actually causing the issue and disable it.
Post is rather old and not closely related to Chrome extensions development, but let it be here.
I had same problem when responding on message in callback. The solution is to return true in background message listener.
Here is simple example of background.js. It responses to any message from popup.js.
chrome.runtime.onMessage.addListener(function(rq, sender, sendResponse) {
// setTimeout to simulate any callback (even from storage.sync)
setTimeout(function() {
sendResponse({status: true});
}, 1);
// return true; // uncomment this line to fix error
});
Here is popup.js, which sends message on popup. You'll get exceptions until you un-comment "return true" line in background.js file.
document.addEventListener("DOMContentLoaded", () => {
chrome.extension.sendMessage({action: "ping"}, function(resp) {
console.log(JSON.stringify(resp));
});
});
manifest.json, just in case :) Pay attention on alarm permissions section!
{
"name": "TestMessages",
"version": "0.1.0",
"manifest_version": 2,
"browser_action": {
"default_popup": "src/popup.html"
},
"background": {
"scripts": ["src/background.js"],
"persistent": false
},
"permissions": [
"alarms"
]
}
To me i was using a VPN extension called
Free VPN for Chrome - VPN Proxy VeePN It was causing the error after disabling it only ... the error disappeared
This error is generally caused by one of your Chrome extensions.
I recommend installing this One-Click Extension Disabler, I use it with the keyboard shortcut COMMAND (⌘) + SHIFT (⇧) + D — to quickly disable/enable all my extensions.
Once the extensions are disabled this error message should go away.
Peace! ✌️
If error reason is extension use incognito Ctrl+Shift+N. In incognito mode Chrome does not have extensions.
UPD. If you need some extension in incognito mode e.g. ReduxDevTools or any other, in extension settings turn on "Allow in incognito"
Make sure you are using the correct syntax.
We should use the sendMessage() method after listening it.
Here is a simple example of contentScript.js It sendRequest to app.js.
contentScript.js
chrome.extension.sendRequest({
title: 'giveSomeTitle', params: paramsToSend
}, function(result) {
// Do Some action
});
app.js
chrome.extension.onRequest.addListener( function(message, sender,
sendResponse) {
if(message.title === 'giveSomeTitle'){
// Do some action with message.params
sendResponse(true);
}
});
For those coming here to debug this error in Chrome 73, one possibility is because Chrome 73 onwards disallows cross-origin requests in content scripts.
More reading:
https://www.chromestatus.com/feature/5629709824032768
https://www.chromium.org/Home/chromium-security/extension-content-script-fetches
This affects many Chrome extension authors, who now need to scramble to fix the extensions because Chrome thinks "Our data shows that most extensions will not be affected by this change."
(it has nothing to do with your app code)
UPDATE: I fixed the CORs issue but I still see this error. I suspect it is Chrome's fault here.
In my case it was a breakpoint set in my own page source. If I removed or disabled the breakpoint then the error would clear up.
The breakpoint was in a moderately complex chunk of rendering code. Other breakpoints in different parts of the page had no such effect. I was not able to work out a simple test case that always trigger this error.
I suggest you first disable all the extensions then one by one enable them until you find the one that has caused the issue in my case Natural Reader Text to Speech was causing this error so I disabled it. nothing to do with Cross-Origin Read Blocking (CORB) unless the error mention Cross-Origin then further up the tread it is worthwhile trying that approach.
I faced the same error in my react project running.
That error coming from my chrome
IObit Surfing Protection
2.2.7
extensions. That extension off my error was solved.
If you face same like that error, 1st turn off your chrome ad blocker or any other extensions while running.
Late here but in my case it was Kaspersky Cloud Protection Extension. I disabled it. It worked all good.
The cause of this issue is related to one of your chrome extensions, not CORS or CORB. To fix that you can turn off each and every chrome extension you installed.
Norton Safe Web extension for chrome is throwing this error message for me. After I disabled this extension, the error message disappeared.
Just cleaning site cookies worked here.
In my case i had to switch off "Adblock extension" from chrome.

Why stub in cypress may not work for route called after page was loaded

I am using cypress to write tests and have a problem which doesn't appear in every test. In some cases it works and I don't know why. So...
The Problem:
I defined a route and alias for it in beforeEach:
beforeEach(function () {
cy.server()
cy.route('GET', '/favourites?funcName=columnPreset', []).as('columnPresetEmpty')
cy.visit('#/search')
})
Stub works fine if http request occured on page load.
But if I perform request responding to click event (modal dialog opens and executes http request) it just appear in commands not makred as stubbed and following cy.wait('#columnPresetEmpty') fails with request timeout.
it('does not work', function () {
cy.get('[data-test=button-gridSettings]').click()
cy.wait('#columnPresetEmpty')
})
At the same time in other tests I have almost similar functionality where request is performed just by clicking on a button, without opening new modal window. It's the only difference.
What am I doing wrong?
The issue might be cypress can not yet fully handle fetch calls. You can disable it the following way but make sure you have fetch polyfill. This will then issue XHR requests which cypress can observe.
cy.visit('#/search', {
onBeforeLoad: (win) => {
win.fetch = null
}
})
More to read here:
https://github.com/cypress-io/cypress/issues/95#issuecomment-281273126
I found the reason causing such behavior. Problem was not in a modal window itself, but code performing second request was called in promise's callback of another request. Something like:
fetch('/initData')
.then(loadView)
And loadView function executed second fetch.
So when I removed loadView from promise's callback both requests become visible for cypress.
For info, I tried it out on my search modal (in a Vue app) and it works ok.
What I did:
created a dummy file named test-get-in-modal.txt in the app's static folder
added an http.get('test-get-in-modal.txt') inside the modal code, so it only runs after the modal is open
in the spec, did a cy.server(), cy.route('GET', 'test-get-in-modal.txt', []).as('testGetInModal') in a before()
in the it() added cy.wait('#testGetInModal') which succeeded
changed to cy.route('GET', 'not-the-file-you-are-looking-for.txt'..., which failed as expected
The only difference I can see is that I cy.visit() the page prior to cy.server(), which is not the documented pattern but seems to be ok in this scenario.

Cypress seems to have stalled

I'm new to cypress and love the way it is architected. However, I seem to have run into a problem early on for a very simple thing that I'm trying to do.
My workflow is:
1) Visit the site
2) Enter username and password
3) On the next screen, type a number and press submit,
4) On the next screen, select a value from a dropdown and press enter.
5) I get to the landing page of my website.
Cypress works totally fine till step 4). It seems to stall at step 5. The test runner suddenly stalls and without warning or error, shows
"Whoops, there is no test to run."
From here, when I click the "View All Tests" button, it takes me to the runner tool. There I see the indication that something is still running in the background. I tried waiting for more than 10 minutes but nothing happens until I click on the "Stop" action.
How do I debug this? Can I see what is happening via any log etc?
There could even be something wrong with my website as well, but without any log information, I'm unable to proceed further. Any help is appreciated.
To provide more context, I don't think this is a timeout based issue as if that were the case, cypress did report to me about this and stopped. I then increased the timeout.
My spec file
describe('My first test', function() {
it('Visits home page', function() {
cy.visit('https://mywebsite.com:5800', {timeout: 400000}, {pageLoadTimeout: 400000}, {defaultCommandTimeout: 400000})
cy.get('#USERNAME').type('myusername')
cy.get('#PASSWORD').type('mypassword')
cy.get('#loginbutton').click()
cy.get('#SOMELEMENT_WHERE_I_TYPE_A_UNIQUE_NUMBER').type('8056')
cy.get('#loginbutton').click()
cy.get('#loginbutton').click()
})
})
Thanks.
If you run DEBUG=cypress:* cypress open from the terminal when initially opening Cypress, there will be more debug log information printed there while you run your tests.
Also, it's always a good idea to search the issues for the project to see if anyone else has had this happen.
For some reason, the Cypress automation gets into a state where it thinks that you have no spec file. All Cypress does to determine this is to see if there is a location.hash defined on the main window -> where it usually says https://localhost:2020/__/#tests/integration/my_spec.js.
Likely this is due to security mechanisms in the app that prevent your application from being run within an iframe (which is how Cypress runs all applications under test). Maybe in your application code it is something like:
if (top !== self) {
top.location.href = self.location.href;
}
You can simply disable these checks while testing or in Cypress you can add to your test file (or a support file to have it work on every test file):
Cypress.on('window:before:load', (win) => {
Object.defineProperty(win, 'self', {
get: () => {
return window.top
}
})
})
I had the same issue. Usually this is related to the page moving out of the parent and can be solved by invoking the attribute and changing it to the current page.
cy.get('.approved-content .no-auto-submit').invoke('attr', 'target', '_self');

How to terminate long poll Ajax request at page leaving

I have long poll Ajax request. Browser, at least but not last IE doesn't terminate the request at page leaving, so request remains open and active even if a user visits some other site. Say more, a browser can successfully process responses from this connection, although their result go nowhere. General recommendations as call htmlxml connection abort or stop for a window obviously do not work.
So my implementation is adding extra Ajax call on unload to notify server connection holder that page is on leave, so it can send some dummy response and a browser will return the connection to pool of available after. This approach works but looks for me over engineered. Unfortunately I can observe a similar problem with some other programs, like GMAIL, it also does long poll and as result after some reloading it stops working. So if somebody found some good approach to address the problem without switching to short poll or assign connection timeout, then share your solution.
There's an abort() method on IE's XHR which will manually disconnect it.
It's a bit hacky, but you could try something like:
<body onbeforeunload="AbortMyAjax()">
and use that method to abort any active long-polls.
For reference, here's a bit of code from a project of mine:
$this.lp = null;
function _LongPoll() {
$.ajaxSetup({ cache: false });
$this.lp = $.getJSON(m_PollUrl, _LongPollCallback);
}
And in the body beforeunload:
if(!!QueueManager.lp && !!QueueManager.lp.abort) QueueManager.lp.abort('PAGE_CLOSED');

How to Stop the page loading in firefox programmatically?

I am running several tests with WebDriver and Firefox.
I'm running into a problem with the following command:
WebDriver.get(www.google.com);
With this command, WebDriver blocks till the onload event is fired. While this can normally takes seconds, it can take hours on websites which never finish loading.
What I'd like to do is stop loading the page after a certain timeout, somehow simulating Firefox's stop button.
I first tried execute the following JS code every time that I tried loading a page:
var loadTimeout=setTimeout(\"window.stop();\", 10000);
Unfortunately this doesn't work, probably because :
Because of the order in which scripts are loaded, the stop() method cannot stop the document in which it is contained from loading 1
UPDATE 1: I tried to use SquidProxy in order to add connect and request timeouts, but the problem persisted.
One weird thing that I found today is that one web site that never stopped loading on my machine (FF3.6 - 4.0 and Mac Os 10.6.7) loaded normally on other browsers and/or computers.
UPDATE 2: The problem apparently can be solved by telling Firefox not to load images. hopefully, everything will work after that...
I wish WebDriver had a better Chrome driver in order to use it. Firefox is disappointing me every day!
UPDATE 3: Selenium 2.9 added a new feature to handle cases where the driver appears to hang. This can be used with FirefoxProfile as follows:
FirefoxProfile firefoxProfile = new ProfilesIni().getProfile("web");
firefoxProfile.setPreference("webdriver.load.strategy", "fast");
I'll post whether this works after I try it.
UPDATE 4: at the end none of the above methods worked. I end up "killing" the threads that are taking to long to finish. I am planing to try Ghostdriver which is a Remote WebDriver that uses PhantomJS as back-end. PhantomJS is a headless WebKit scriptable, so i expect not to have the problems of a real browser such as firefox. For people that are not obligate to use firefox(crawling purposes) i will update with the results
UPDATE 5: Time for an update. Using for 5 months the ghostdriver 1.1 instead FirefoxDriver i can say that i am really happy with his performance and stability. I got some cases where we have not the appropriate behaviour but looks like in general ghostdriver is stable enough. So if you need, like me, a browser for crawling/web scraping purposes i recomend you use ghostdriver instead firefox and xvfb which will give you several headaches...
I was able to get around this doing a few things.
First, set a timeout for the webdriver. E.g.,
WebDriver wd;
... initialize wd ...
wd.manage().timeouts().pageLoadTimeout(5000, TimeUnit.MILLISECONDS);
Second, when doing your get, wrap it around a TimeoutException. (I added a UnhandledAlertException catch there just for good measure.) E.g.,
for (int i = 0; i < 10; i++) {
try {
wd.get(url);
break;
} catch (org.openqa.selenium.TimeoutException te) {
((JavascriptExecutor)wd).executeScript("window.stop();");
} catch (UnhandledAlertException uae) {
Alert alert = wd.switchTo().alert();
alert.accept();
}
}
This basically tries to load the page, but if it times out, it forces the page to stop loading via javascript, then tries to get the page again. It might not help in your case, but it definitely helped in mine, particularly when doing a webdriver's getCurrentUrl() command, which can also take too long, have an alert, and require the page to stop loading before you get the url.
I've run into the same problem, and there's no general solution it seems. There is, however, a bug about it in their bug tracking system which you could 'star' to vote for it.
http://code.google.com/p/selenium/issues/detail?id=687
One of the comments on that bug has a workaround which may work for you - Basically, it creates a separate thread which waits for the required time, and then tries to simulate pressing escape in the browser, but that requires the browser window to be frontmost, which may be a problem.
http://code.google.com/p/selenium/issues/detail?id=687#c4
My solution is to use this class:
WebDriverBackedSelenium;
//When creating a new browser:
WebDriver driver = _initBrowser(); //Just returns firefox WebDriver
WebDriverBackedSelenium backedSelenuium =
new WebDriverBackedSelenium(driver,"about:blank");
//This code has to be put where a TimeOut is detected
//I use ExecutorService and Future<?> Object
void onTimeOut()
{
backedSelenuium.runScript("window.stop();");
}
It was a really tedious issue to solve. However, I am wondering why people are complicating it. I just did the following and the problem got resolved (perhaps got supported recently):
driver= webdriver.Firefox()
driver.set_page_load_timeout(5)
driver.get('somewebpage')
It worked for me using Firefox driver (and Chrome driver as well).
One weird thing that i found today is that one web site that never stop loading on my machine (FF3.6 - 4.0 and Mac Os 10.6.7), is stop loading NORMALy in Chrome in my machine and also in another Mac Os and Windows machines of some colleague of mine!
I think the problem is closely related to Firefox bugs. See this blog post for details. Maybe upgrade of FireFox to the latest version will solve your problem. Anyway I wish to see Selenium update that simulates the "stop" button...
Basically I set the browser timeout lower than my selenium hub, and then catch the error. And then stop the browser from loading, then continue the test.
webdriver.manage().timeouts().pageLoadTimeout(55000);
function handleError(err){
console.log(err.stack);
};
return webdriver.get(url).then(null,handleError).then(function () {
return webdriver.executeScript("return window.stop()");
});
Well , the following concept worked with me on Chrome , try the same:
1) Navigate to "about:blank"
2) get element "body"
3) on the elemënt , just Send Keys Ësc
Just in case someone else might be stuck with the same forever loading annoyance, you can use simple add-ons such as Killspinners for Firefox to do the job effortlessly.
Edit : This solution doesn't work if javascript is the problem. Then you could go for a Greasemonkey script such as :
// ==UserScript==
// #name auto kill
// #namespace default
// #description auto kill
// #include *
// #version 1
// #grant none
// ==/UserScript==
function sleep1() {
window.stop();
setTimeout(sleep1, 1500);
}
setTimeout(sleep1, 5000);

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