I am using sails-mongo with Sails v0.12.13 and realize that if mongodb stops, when I do some request to the controller (using curl) the request get stucked for a while and then returns no error in the application logs. I just get the message on the curl console:
curl: (52) Empty reply from server
Here is my code snippet:
model.find()
.then((result) => {
options.status = true;
return callback(null, getResponse(null, name, options));
})
.catch((err) => {
options.status = false;
return callback(err, getResponse(err, name, options));
});
Tried to put logs into the catch blocks but nothing was printed.
Am I missing something or is there a problem with sails-mongo adapter on dealing with a connection loss?
Related
I'm working with the HttpService module from Nest.js to make the HTTP calls. I'm able to download an image from https://unsplash.com; when there is no network interruptions the code is working as expected.
This is the code I have for making the download call and start writing into the desired file
const urlDownload = 'https://unsplash.com/photos/xiie4XeSzTU/download?force=true';
let response = await this.httpService.get(urlDownload, {
responseType: 'stream'
}).toPromise();
response.data.pipe(writer);
And this is the code where I'm trying to handle the possible events of the writer and returning a response
let downloadFile = path.resolve(__dirname,'../../files/landscape.jpg');
let writer = fs.createWriteStream(downloadFile);
return new Promise((resolve, reject) => {
writer.on('finish', ()=>{
resolve('Image downloaded');
});
writer.on('error', ()=>{
reject('Image downloaded failed');
});
});
I'm deliberately turning off the wifi during the download to try the server response with Image downloaded failed (what I have in the writer error handler), but instead I'm getting an 500 statusCode, internal server error. When I go to the Nest console to whatch the error it appears
[Nest] 11220 - 2020-05-22 18:16:45 [ExceptionsHandler] getaddrinfo ENOTFOUND unsplash.com +439536ms
Error: getaddrinfo ENOTFOUND unsplash.com
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:64:26)
How can I solve this and catch correcty the network error from Nest to return a friendly message?
I could solve it. I let it here with the hope of helping somebody in the future.
It is not firing the error handler function because that handler is attached to the writter, and there is not writting error, it just stops writing because the cut of the connection but that is not an error.
I re-writed the response variable to stop being a promise and better I started treating it like an observer.
let response = this.httpService.get(urlDownload, {
responseType: 'stream',
});
And then it is the response in previus Promise format
return new Promise((resolve, reject) => {
writer.on('error', () => {
resolve('error due to, possibly, an unexisting file path');
})
response.subscribe({
next(response) { response.data.pipe(writer) },
error(err) {
console.error('More details: ' + err);
resolve('Error in the download :/')
},
complete() { resolve('Completed'); }
})
});
I'm not using the reject function of the promise but it is perfectly doable
I am writing some end-to-end test cases to test socket connections in my app. I expect receiving socket events after specific rest API requests. For instance, after hitting: /api/v1/[createTag], I expect receiving createTag event to be captured by socket.io-client. The issue is that, it is very inconsistently passing, and sometimes failing, with good rest API requests. The reason to fail is that done() event inside socket.on('createTag' ... is never called, so it gets timeout. On browser, currently all the API endpoints and sockets seem to be working fine. Is there a specific configuration that I might be missing in order to test socket.io-client within Node.js environment and Jest?
Below is my test cases, and thanks a lot in advance:
describe('Socket integration tests: ', () => {
beforeAll(async done => {
await apiInit();
const result = await requests.userSignIn(TEST_MAIL, TEST_PASSWORD);
TEST_USER = result.user;
SESSION = result.user.session;
console.log('Test user authenticated succesfully.');
done();
});
beforeEach(done => {
socket = io(config.socket_host, { forceNew: true })
socket.on('connect', () => {
console.log('Socket connection succesful.');
socket.emit('session', { data: SESSION }, (r) => {
console.log('Socket session successful.');
done();
});
});
})
test('Receiving createTag socket event?', async(done) => {
console.log('API request on createTag');
const response = await Requester.post(...);
console.log('API response on createTag', response);
socket.on('createTag', result => {
console.log('createTag socket event succesful.');
createdTagXid = result.data.xid;
done();
})
});
afterEach(done => {
if(socket.connected) {
console.log('disconnecting.');
socket.disconnect();
} else {
console.log('no connection to break');
}
done();
})
}
Basically, setting event handles after async API calls seems to be the issue. So I should have first set the socket.on( ... and then call rest API.
I was trying to pass my data from mongodb/express to react using componentDidMount() life cycle function but for some reason it doesn't work but instead it gives me this "Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0" error.
Here's how I set up my express:
app.get('/movies', function(req, res){
movie.find({}, function(err, allMovies){
if(err){
console.log(err);
} else {
res.send(allMovies);
}
})
});
app.listen(3000, function(){
console.log('App server is listening to 3000');
});
And inside my react file I call the componentDidMount function which is running via webpack at port 8080.
componentDidMount() {
console.log('test')
fetch('/movies')
.then(response => response.json())
.then(movies => this.setState({
movies: movies
}));
}
when i console.log response it returns this https://prnt.sc/iye6kk.
Any idea what am I doing wrong why my data is not passing properly?
In componentDidMount,script is parsing the response to JSON.
.then(response => response.json())
But server is not sending the response in the JSON format.
Send it in json format.
res.json({allMovies}); //ecma6 shorthand property names
Or
res.json({allMovies : allMovies});
I have been using MLab MongoDB and mongoose library to create a db connection inside a serverless (Lambda) handler. It works smoothly on local machine. But sometimes it doesn't work after deployment.The request returns an Internal server error. The weird thing is sometimes it works. But If I remove the database connection code, the handler works. The serverless log just says Process exited before completing request. No real errors so no idea what to do.
The db connection looks like this:
handler.js
// Connect to database
mongoose.connect(process.env.DATABASE_URL, {
useMongoClient: false
}).then((ee) => {
console.log('------------------------invoke db ', ee);
})
.catch(err => console.error('-----------error db ', err));
No error in here too. Any idea what's happening?
When you get Process exited before completing request, it means that the node process has crashed before Lambda was able to call callback. If you go to Cloudwatch logs, there would be an error and stack trace of what happened.
You should connect to the MongoDB instance inside your handler and before you call callback(), disconnect first.
It would be like this...
exports.handler = (event, context, callback) => {
let response;
return mongoose.connect(process.env.DATABASE_URL, {
useMongoClient: false
}).then((ee) => {
// prepare your response
response = { hello: 'world' }
}).then(() => {
mongoose.disconnect()
}).then(() => {
// Success
callback(null, response)
}).catch((err) => {
console.error(err);
callback(err);
})
};
Here is an article explaining with details how lambda work with node and an example of how to implement DB connection.
Differently of #dashmug suggested, you should NOT disconnect your DB since connecting every time will decrease your performance.
I have a mongoose schema with a unique field and I am trying to write a backend (express) integration test which checks that POSTing the same entity twice results in HTTP 400. When testing manually behaviour is as excpected. Automatic testing however requires a wait:
it('should not accept two projects with the same name', function(done) {
var project = // ...
postProjectExpect201(project,
() => {
setTimeout( () => {
postProjectExpect400(project, done);
},100);
}
);
});
The two post... methods do as named and the code above works fine, but if the timeout is removed, BOTH requests receive HTTP 200 (though only one entity created in the database).
I'm new to those technologies and I'm not sure what's going on. Could this be a mongodb related concurrency issue and if so how should I deal with it?
The database call looks like this:
Project.create(req.body)
.then(respondWithResult(res, 201))
.catch(next);
I already tried connecting to mongodb with ?w=1 option btw.
Update:
To be more verbose: Project is a mongoose model and next is my express error handler which catches the duplicate error.
The test functions:
var postProjectExpect201=function(project, done, validateProject) {
request(app)
.post('/api/projects')
.send(project)
.expect(201)
.expect('Content-Type', /json/)
.end((err, res) => {
if (err) {
return done(err);
}
validateProject && validateProject(res.body);
done();
});
};
var postProjectExpect400=function(project, done) {
request(app)
.post('/api/projects')
.send(project)
.expect(400)
.end((err, res) => {
if (err) {
return done(err);
}
done();
});
};