handle http errors in rxjs lastValueFrom - rxjs

I have started to use the lastValueFrom() to handle my observable http requests. One of these http calls is returning an error from the server-side, and I am getting the name: 'EmptyError', message: 'no elements in sequence' message
const response = await lastValueFrom(
this.service.doStuff()
).catch((e) => {
console.log('#1', e);
return {} as DoStuffResponse;
});
at #1 the error is EmptyError , not the error from the http call.
I understand why I am getting it (the http observable does not return a value)
However, what I'd like to know is what the actual error is (a 422 unprocessable entity in this case)
Is this possible ?

I have not found a method to catch the Http errors from lastValueFrom and this does not appear to be documented in rxjs.
As a result I've decided to avoid lastValueFrom when doing Http requests. Instead I stick with Subscribe and always get the Http response codes in the error.
As an aside, many people noticed Subscribe as being deprecated in VSCode, but this is not true; just a certain overload. I know you didn't mention the deprecation as a motivator for using lastValueFrom, but I think most people, including myself, used the VSCode deprecation alert as a prompt to switch.
That said, this Subscribe syntax is still valid and should give you the Http error code:
this.someService.getResults.subscribe(
{
next: (results) => {
console.log('Here are the results...', results);
},
error: (err: any) => {
console.log('Here is the error...', err.status);
},
complete: () => { }
});

Related

A callback was provided to intercept the upstream response, but a network error occurred while making the request

I am using the method described in the answer of this question Log network failures in Cypress to log network failures. I basically intercept every failing request and its response and log it in some array as follows:
cy.intercept('*', (request) => {
request.continue(response => {
if(response.statusMessage !== "OK") {
networkFails.push({request, response})
}
})
})
The tests run perfectly fine, the problem is at the end of the tests I get this error
How do I solve this problem?
I ran into the same issue, and it turns out using request.continue is what was causing it.
request.continue is expecting a response, but when you get a socket hangup (ConnResetException), or in my case the socket being closed before it was finished writing, it triggers a cypress error.
Instead of request.continue, you'll want to use request.on( 'response', response => {
Your full code snippet should look like this:
cy.intercept('*', (request) => {
request.on( 'response', response => {
if(response.statusMessage !== "OK") {
networkFails.push({request, response})
}
})
})
The cypress documentation does a great job of explaining all of the different options here: https://docs.cypress.io/api/commands/intercept#Request-events
For reference, this was the specific cypress error I was getting while using .continue(). The error message was a bit different from yours but essentially the same problem requiring the same solution.
A callback was provided to intercept the upstream response, but a network error occurred while making the request:
Error: Socket closed before finished writing response

Can Sentry catch network error (XHR or fetch) in browser?

I am currently integrating Sentry into an Angular web application.
I am successfully reporting console.log / warn / error and exceptions in Sentry as "issue".
However, when a request to my server fails (HTTP 4XX or 5XX), Sentry totally ignores this error and does not send it.
I have tried all possible values for tracingOrigins.
Sentry.init({
dsn: '******',
integrations: [
new CaptureConsole(),
new Integrations.BrowserTracing({
tracingOrigins: ['localhost', 'http://localhost:4646/api']
})
],
tracesSampleRate: 1.0,
debug: true
});
What can I do ?
You can use the unhandled rejection event found here: https://developer.mozilla.org/en-US/docs/Web/API/Window/unhandledrejection_event
When your promises fail and error out, but are uncaught, this event will fire. Here you can add Sentry.captureException.
However the fact that you have CaptureConsole means you are likely sending all console errors as sentry events, and uncaught 4xx and 5xx should be sent. I assume you are catching and handling these then?
One way to handle these is add Sentry.captureException in your fetch/xhr library when it processes the response object.
If its easier to just log every uncaught error, you can patch the Promise object:
window.Promise = class extends Promise {
catch(func, ...args) {
let loggingFunc = (error = {}, ...args) => {
console.warn('Promise caught', error);
Sentry.breadcrumb('Promise caught', error.message, Sentry.Severity.Error);
return func(error, ...args);
};
return super.catch(loggingFunc, ...args);
}
};
I think you'd want an instance of Sentry running on your server to capture backend errors. You'd probably want to set these up in Sentry as two different projects.
Alternatively, you could manually track them in your Angular app when you get the response back - something like Sentry.captureException(err);

Cypress interception is not waiting

I'm using Cypress 6.0.0 new way of interception.
Waiting on a request
I need to wait for the "templatecontract" response in order to click the #template-button-next because otherwise is disabled. But is trying to click it before getting the response from the API. The documentation seems pretty straight forward.
Am I wrong here?
I have also tried just like:
cy.wait('#templatecontract')
cy.get('#template-button-next').click()
it("Test", function() {
cy.intercept(Cypress.env("baseUrl")+`/api/v1/contract-type/templatecontract`).as('templatecontract')
cy.login(Cypress.env('testUserInviteEmail'), Cypress.env('testUserInvitePassword')).then((token) => {
cy.visit(Cypress.env('baseUrl')+"/templates", {headers: {
Authorization: token,
},
});
cy.get('a[href="/create-template"]').click();
cy.get('.template-usecasetitle').contains('UBO-Formular')
cy.get('button[cy-data="Formular"]').click();
cy.get('#title').type("Title for testing");
cy.get('#usecasetitle').type("Usecasetitle for testing")
cy.get('#description').type("Description just for testing")
cy.wait('#templatecontract').then(interceptions => {
cy.get('#template-button-next').click()
});
});
});
I'm not sure why but just setting the method type (POST in this case) have solved the problem.
cy.intercept('POST', Cypress.env("baseUrl")+`/api/v1/contract-type/templatecontract`).as('templatecontract')
I had a similar problem, and the issue was that the first request my application sent was an OPTIONS request.
If you do not include the method as the first argument, all methods (including OPTIONS) are now matched. This can be puzzling as your .wait will be satisfied by the OPTIONS request, not by your second POST request.
Reference: https://docs.cypress.io/api/commands/intercept.html#Comparison-to-cy-route
Reference: https://docs.cypress.io/api/commands/intercept.html#Matching-URL
Interestingly I am getting different results for
cy.intercept("POST", "https://backend.rocketgraph.app/api/signup").as("doSignup")
and
cy.intercept("POST", `${BACKEND_URL}/signup`).as("doSignup")
Not sure what is the issue. Also have to set POST as one of the users have mentioned
The first one is actually intercepted. Weird but happened.
If you spy a route at the top of your test, as you do here, cy.wait() will return immediately if there have already been responses to that route by the time it's called.
As an example, say you notice this in your network tab:
GET some-route: 200
GET some-route: 200
GET some-route: 200
GET some-route: 200
POST something-unique: 200
GET some-route: 500
^ some-route is 500ing at some clearly-identifiable point. Should be easy to catch in a test, right? Well:
it('Should fail on this 500, but doesn't???', () => {
// start spying our indicator; seems good:
cy.intercept('GET', 'something-unique').as('indicator')
// but if we start spying the route here:
cy.intercept('POST', 'some-route').as('route')
// then hit some-route a bunch of times & return:
foo()
// then expect to catch the failure after something-unique fires:
cy.wait('#indicator').its('response.statusCode').should('eq', 200).then( () => {
// then expect the test to fail on the 500:
cy.wait('#route').its('response.statusCode).should('not.eq', 500)
// ...this won't work! this test will pass because cy.wait() will
// succeed and return the *first* GET some-route: 200 !
})
I personally find this to be pretty counter-intuitive - it feels reasonable that a wait() on a spied route would always actually wait for the next request! - but that's apparently not how it works.
One way around this is to not start spying until you're actually ready:
it('Fails on a 500', () => {
cy.intercept('GET', 'something-unique').as('indicator')
foo()
cy.wait('#indicator').its('response.statusCode').should('eq', 200).then( () => {
// don't start spying until ready:
cy.intercept('POST', 'some-route').as('route')
cy.wait('#route').its('response.statusCode).should('not.eq', 500)
// and the test fails correctly; response.statusCode 500 should not equal 500
})

Axios Reponse Interceptor : unable to handle an expired refresh_token (401)

I have the following interceptor on my axios reponse :
window.axios.interceptors.response.use(
response => {
return response;
},
error => {
let errorResponse = error.response;
if (errorResponse.status === 401 && errorResponse.config && !errorResponse.config.__isRetryRequest) {
return this._getAuthToken()
.then(response => {
this.setToken(response.data.access_token, response.data.refresh_token);
errorResponse.config.__isRetryRequest = true;
errorResponse.config.headers['Authorization'] = 'Bearer ' + response.data.access_token;
return window.axios(errorResponse.config);
}).catch(error => {
return Promise.reject(error);
});
}
return Promise.reject(error);
}
);
The _getAuthToken method is :
_getAuthToken() {
if (!this.authTokenRequest) {
this.authTokenRequest = window.axios.post('/api/refresh_token', {
'refresh_token': localStorage.getItem('refresh_token')
});
this.authTokenRequest.then(response => {
this.authTokenRequest = null;
}).catch(error => {
this.authTokenRequest = null;
});
}
return this.authTokenRequest;
}
The code is heavily inspired by https://github.com/axios/axios/issues/266#issuecomment-335420598.
Summary : when the user makes a call to the API and if his access_token has expired (a 401 code is returned by the API) the app calls the /api/refresh_token endpoint to get a new access_token. If the refresh_token is still valid when making this call, everything works fine : I get a new access_token and a new refresh_token and the initial API call requested by the user is made again and returned correctly.
The problem occurs when the refresh_token has also expired.
In that case, the call to /api/refresh_token returns a 401 and nothing happens. I tried several things but I'm unable to detect that in order to redirect the user to the login page of the app.
I found that in that case the if (!this.authTokenRequest) statement inside the _getAuthToken method returns a pending Promise that is never resolved. I don't understand why this is a Promise. In my opinion it should be null...
I'm a newbie with Promises so I may be missing something !
Thanks for any help !
EDIT :
I may have found a way much simpler to handle this : use axios.interceptors.response.eject() to disable the interceptor when I call the /api/refresh_token endpoint, and re-enable it after.
The code :
createAxiosResponseInterceptor() {
this.axiosResponseInterceptor = window.axios.interceptors.response.use(
response => {
return response;
},
error => {
let errorResponse = error.response;
if (errorResponse.status === 401) {
window.axios.interceptors.response.eject(this.axiosResponseInterceptor);
return window.axios.post('/api/refresh_token', {
'refresh_token': this._getToken('refresh_token')
}).then(response => {
this.setToken(response.data.access_token, response.data.refresh_token);
errorResponse.config.headers['Authorization'] = 'Bearer ' + response.data.access_token;
this.createAxiosResponseInterceptor();
return window.axios(errorResponse.config);
}).catch(error => {
this.destroyToken();
this.createAxiosResponseInterceptor();
this.router.push('/login');
return Promise.reject(error);
});
}
return Promise.reject(error);
}
);
},
Does it looks good or bad ? Any advice or comment appreciated.
Your last solution looks not bad. I would come up with the similar implementation as you if I were in the same situation.
I found that in that case the if (!this.authTokenRequest) statement inside the _getAuthToken method returns a pending Promise that is never resolved. I don't understand why this is a Promise. In my opinion it should be null...
That's because this.authTokenRequest in the code was just assigned the Promise created from window.axios.post. Promise is an object handling kind of lazy evaluation, so the process you implement in then is not executed until the Promise was resolved.
JavaScript provides us with Promise object as kind of asynchronous event handlers which enables us to implement process as then chain which is going to be executed in respond with the result of asynchronous result. HTTP requests are always inpredictable, because HTTP request sometimes consumes much more time we expect, and also sometimes not. Promise is always used when we use HTTP request in order to handle the asynchronous response of it with event handlers.
In ES2015 syntax, you can implement functions with async/await syntax to hanle Promise objects as it looks synchronous.

How to get more error information from an Angular http ajax call

I have been trying to diagnose a http problem for what seems forever now.
I thought I would go back to a very simple sample Ionic (Angular) application I can use to test, where I have the following test code...
public onClick() : void {
this.http.get(this.url).subscribe(res => {
this.result = res.statusText;
console.log(res);
}, error => {
this.result = `failed ${error.statusText}`;
console.log(error);
});
}
The url just comes from an input.
If I force an error, (eg put an incorrect url), I notice the error from the observable always has a status os 0, and no statusText. In the browser network tab, I see the 404 as expected...
identityx 404 xhr polyfills.js:3 160 B 10 ms
Is there a way to get better error information back from the http call, rather than just 0 all the time (and no status text)? I've look through the error object, but can't see anything.
Thanks in advance!

Resources