I would like to test a method which execute a POST on another server :
Future executePost() {
_client.post("http://localhost/path", body : '${data}').then((response) {
_logger.info("Response status : ${response.statusCode}");
_logger.info("Response body : ${response.body}");
Completer completer = new Completer();
completer.complete(true);
return completer.future;
}).catchError((error, stackTrace) {
_logger.info(error);
_logger.info(stackTrace);
});
}
The problem I'm dealing with is that my testing method ends before the future returned by "_client.post" is executed.
My testing method :
test('should be true', () {
try {
Future ok = new MyClient().executePost();
expect(ok, completion(equals(true)));
} catch(e, s) {
_logger.severe(e);
_logger.severe(s);
}
});
Thanks for your help !
Your executePost() method doesn't even return a future, it returns null.
client.post() returns a future but this return value isn't used.
Try to change it to:
Future executePost() {
return _client.post("http://localhost/path", body : '${data}').then((response) {
_logger.info("Response status : ${response.statusCode}");
_logger.info("Response body : ${response.body}");
return true;
}).catchError((error, stackTrace) {
_logger.info(error);
_logger.info(stackTrace);
});
}
Related
This question already has answers here:
chrome.runtime.onMessage response with async await
(7 answers)
Closed 1 year ago.
I am having an issue of asynchronicity (I believe). sendResponse() in contentscript.js does not wait for getThumbnails() to return.
I am sending a message in popup.js:
chrome.tabs.sendMessage(tabs[0].id, {message: "get_thumbnails", tabUrl: tabs[0].url},
function (respThumbnails) {
const thumbUrl = respThumbnails.payload;
console.log("payload", thumbUrl)
}
);
Then, in contentscript.js I listen for this message:
chrome.runtime.onMessage.addListener(async function(request,sender,sendResponse) {
if(request.message === "get_thumbnails") {
const payload = await getThumbnails();
console.log("thumbPayload after function:", payload)
sendResponse({payload:payload});
}
});
async function getThumbnails() {
let tUrl = null;
var potentialLocations = [
{sel: "meta[property='og:image:secure_url']", attr: "content" },
{sel: "meta[property='og:image']", attr: "content" },
];
for(s of potentialLocations) {
if(tUrl) return
const el = document.querySelector(s.sel);
if(el) {
tUrl = el.getAttribute(s.attr) || null;
}
}
return tUrl;
};
But it is also possible that the problem is coming from my getThumnails() function, because most of the times, payload is null and not undefined. So getThumbnails() might return before it is completely executed.
If this is the case, I have no idea why...
I also tried this code for getThubnails():
async function getThumbnails() {
let x = await function() {
let tUrl = null;
var potentialLocations = [
{sel: "meta[property='og:image:secure_url']", attr: "content" },
{sel: "meta[property='og:image']", attr: "content" },
];
for(s of potentialLocations) {
if(tUrl) return
const el = document.querySelector(s.sel);
if(el) {
tUrl = el.getAttribute(s.attr) || null;
}
}
return tUrl;
}
return x;
};
But this does not work, it seems to break my code...
The callback of onMessage should return a literal true value (documentation) in order to keep the internal messaging channel open so that sendResponse can work asynchronously.
Problem
Your callback is declared with async keyword, so it returns a Promise, not a literal true value. Chrome extensions API doesn't support Promise in the returned value of onMessage callback until https://crbug.com/1185241 is fixed so it's just ignored, the port is immediately closed, and the caller receives undefined in response.
Solutions
Remove the async keyword from before (request, sender, sendResponse), then...
Solution 1
Call an async function that can be embedded as an IIFE:
chrome.runtime.onMessage.addListener((request, sender, sendResponse) => {
if (request.message === "get_thumbnails") {
(async () => {
const payload = await getThumbnails();
console.log("thumbPayload after function:", payload)
sendResponse({payload});
})();
return true; // keep the messaging channel open for sendResponse
}
});
Solution 2
Declare a separate async function and call it from the onMessage listener:
chrome.runtime.onMessage.addListener((msg, sender, sendResponse) => {
if (msg.message === "get_thumbnails") {
processMessage(msg).then(sendResponse);
return true; // keep the messaging channel open for sendResponse
}
});
async function processMessage(msg) {
console.log('Processing message', msg);
// .................
return 'foo';
}
My method processData() is executing before pullAllData() is finished but I need processData() to wait until pullAllData() is completely finished before running. This is causing my isDownloadSuccessful bool to be Null when processData() is ran.
Future getCoinData() async {
calculateNumberOfDataPoints();
pullTimesAndPrices();
return timesAndPrices;
}
Future pullTimesAndPrices() async {
for (String cryptoCurrency in cryptoAbbreviation) {
pullAllData(cryptoCurrency);
processData(cryptoCurrency);
}
}
Future pullAllData(cryptoCurrency) async {
String historicalRequestURL =
'$cryptoAPIURL$cryptoCurrency$currency/ohlc?periods=$periodValue&apikey=$apiKey';
http.Response historicalResponse = await http.get(historicalRequestURL);
isPullSuccessful = (historicalResponse.statusCode == 200);
}
void processData(cryptoCurrency) {
if (isPullSuccessful) {
...
} else {
throw 'Problem pulling data';
}
}
You are marking your function pullTimesAndPrices as async but not using await. Use the await keyword before calling the pullAllData function.
So I want to return a value from a subscribe function like this:
async obtenerListadoClases(categoria) {
var clasesDB = await this.getClases(categoria)
.subscribe((data: any) => {
clasesDB = data.clasesDB // **Want to return this**
console.log(clasesDB,'clasesDB'); // **Getting Value**
})
console.log(clasesDB, 'outside'); // **Not Getting Value**
return clasesDB;
}
Also, I want to use this function in another place like this:
var listaClases = await this.claseServicio.obtenerListadoClases(categoria); // Not getting the correct info
// console.log(listaClases , 'listado clases');
What Im doing wrong? Or how can I fix it? Thanks in advance!
You can only subscribe to observables.
The Observable way
getClases(categoria): Observable<any> {
return new Observable(observer => {
// logic to return data
observer.next(data);
observer.complete()
// logic when error
observer.error(error);
});
}
Return the getClases() function
obtenerListadoClases(categoria): Observable<any>{
return this.getClases(categoria);
}
Use the function where you want:
this.obtenerListadoClases(categoria)
.subscribe(
result => {
// what you want to do with the result
},
error => {
// what you want to do with the error
});
The Promise way
getClases(categoria): Promise<any> {
return new Promise((resolve, reject) => {
// logic to return data
resolve(data);
// logic when error
reject(error);
});
}
Return the getClases() function
obtenerListadoClases(categoria): Promise<any>{
return this.getClases(categoria);
}
Use the function where you want:
this.obtenerListadoClases(categoria)
.then(result => {
// what you want to do with the result
})
.catch(error => {
// what you want to do with the error
});
You should be using promises with the .subscribe(). Only observables use .subcribe()
Also, stay away from promises in the angular world. Time to think reactive.
Is this returning an observable? this.getClases(categoria) post the code please.
I have a function which does some asynchronous operations and I want to return the status of the operation back to the caller. How can I achieve this?
Future<bool> setData() async {
Firestore.instance.collection("test").document('$id').setData({
'id': 'test'
}).then((onValue) {
print('Data set success');
return true;
}).catchError((onError) {
print('Data set Error!!!');
return false;
});
}
//Calling
final status = await setData();
if(status){
//do success
}
But this function complains that it doesn't end with a return statement. What is the logical mistake I'm making here?
You miss a return in your setData function
return Firestore.instance....
After many attempts to get the content of the response in HttpRequest, I failed completely to know or understand why I can't have what I want, and I must mention that I can log and manipulate the response only inside an onReadyStateChange (onLoad and onLoadEnd are giving me the same results!), but I really want that value outside the callback.
Here is the part of code that I'm stuck with
Map responsData;
req=new HttpRequest()
..open(method,url)
..send(infojson);
req.onReadyStateChange.listen((ProgressEvent e){
if (req.readyState == HttpRequest.DONE ){
if(req.status == 200){
responsData = {'data': req.responseText};
print("data receaved: ${ req.responseText}");
//will log {"data":mydata}
}
if(req.status == 0){
responsData = {'data':'No server'};
print(responsData );
//will log {"data":No server}
}
}
});
//anything here to get responsData won't work
You have to assign an onLoad callback before you call send.
I'm not sure what you mean with only inside an onReadyStateChange.
Maybe you want to assign the responseText to a variable outside the the callback.
Create a method:
Future<String> send(String method, String url, String infojson) {
var completer = new Completer<String>();
// var result;
req=new HttpRequest()
..open(method,url)
..onLoad.listen((event) {
//print('Request complete ${event.target.reponseText}'))
// result = event.target.responseText;
completer.complete(event.target.responseText);
})
..send(infojson);
return completer.future;
}
and call this method like
var result;
send(method, url).then(
(e) {
// result = e;
print('Request complete ${e}'));
});