I have this piece of code and it is executed with .continueWith and addOnSuccessListener even if failed.I try with continueWithTask but i dont understand very well Tasks API. Please help me to understand how to do this.
db.collection(customGameName).document().get().continueWith {
if (!gameslist.contains(customGameName)) {
gameslist.add(customGameName)
SavedPreference.setGamesList(this, gameslist)
adapter.notifyDataSetChanged()
}else{
Toast.makeText(this,"$customGameName is in the list already!",Toast.LENGTH_SHORT).show()
}
}.addOnFailureListener {
Toast.makeText(this,"$customGameName not exist!",Toast.LENGTH_SHORT).show()
gameslist.remove(customGameName)
SavedPreference.setGamesList(this, gameslist)
adapter.notifyDataSetChanged()
}
If you have code that you only want to run when the task is successful, add a success listener to the task. That should look something like this:
db.collection(customGameName).document().get()
.addOnSuccessListener { document ->
if (document != null) {
Log.d(TAG, "DocumentSnapshot data: ${document.data}")
if (!gameslist.contains(customGameName)) {
gameslist.add(customGameName)
SavedPreference.setGamesList(this, gameslist)
adapter.notifyDataSetChanged()
}else{
Toast.makeText(this,"$customGameName is in the list already!",Toast.LENGTH_SHORT).show()
}
} else {
Log.d(TAG, "No such document")
}
}.addOnFailureListener {
Toast.makeText(this,"$customGameName not exist!",Toast.LENGTH_SHORT).show()
gameslist.remove(customGameName)
SavedPreference.setGamesList(this, gameslist)
adapter.notifyDataSetChanged()
}
Note that this code is pretty much straight from the Firebase documentation on getting a document in Kotlin, so I recommend spending some more time there.
Related
Is it possible to print error on firebase? not create another collection and create document
Example: I called cloud function. but when cloud function failed we can't find which error/error code. Now, I debug application and run cloud function again check with my console. Is there any way to print in firebase?
if (result.data['success']) {
finalize();
} else if (result.data['errorCode'] == 1003) {
print(result.data['errorMessage']);
} else {
print(result.data['errorMessage']);
}
} on CloudFunctionsException catch (e) {
print(e);
} catch (e) {
print(e);
}
And also other errors. api call errors etc
Every error produced by function is stored in Firebase Dashboard -> Function -> Logs (tab). Moreover, when you create your own function, every console.log() is logged there.
I am trying to read a document from a database in firebase and show the info at the UI. Any idea why is it not working?
Viewmodel:
var leid = MediatorLiveData<Gas>()
init {
initializeDocument()
}
fun initializeDocument(){
mFirestore?.collection("expenditures")?.document("ASfavaftaseacdadf")?.get()?.addOnSuccessListener { document ->
if (document != null) {
Log.d("TAG", "DocumentSnapshot data: ${document.data}")
var gastl = document.toObject<Gas>()!!
leid.value=gastl
} else {
Log.d("TAG", "No such document")
}
}
?.addOnFailureListener { exception ->
Log.d("TAG", "get failed with ", exception)
}
}
After that, I use databinding for the UI. When I try to execute the code, I dont get any log or anything; It is like the function never execute.
Thanks in advance.
I started to learn ES6 and I'm transforming my project from ES5 to ES6. I want to ask if it's sense to use async/await in middlewares ? How to use it in this example :
middlewareObj.checkCampground = (req,res,next) =>{
if(req.isAuthenticated()){
Campground.findById(req.params.id, (err, foundCampground) =>{
if(err || !foundCampground){
req.flash("error", "Campground not found");
res.redirect("back");
} else {
if(foundCampground.author.id.equals(req.user._id) || req.user.isAdmin){
next();
} else {
req.flash("error", "You don't have permission to do that");
res.redirect("back");
}
}
});
} else {
req.flash("error", "You need to be logged in to do that");
res.redirect("back");
}
};
When you only have a single asynchronous operation like you do here, you don't gain much (if anything) from switching to await. The bigger benefits come when you need to sequence multiple asynchronous operations and perhaps even have some branching. Then await lets you write much simpler code.
Plus, most of your code here is really just about checking results and getting the right error message back to the user and that doesn't get a lot simpler with await as it's just a bunch of rote checks either way.
Here's an implementation that also attempts to use exceptions to consolidate all the error returns so you don't have as many places where you're doing req.flash() and res.redirect():
middlewareObj.checkCampground = async (req,res,next) => {
try {
if(req.isAuthenticated()) {
throw new Error("You need to be logged in to do that");
}
const foundCampground = await Campground.findById(req.params.id);
if (!foundCampground) {
throw new Error("Campgound not found")
}
if (foundCampground.author.id.equals(req.user._id) || req.user.isAdmin) {
next();
} else {
throw new Error("You don't have permission to do that");
}
} catch(e) {
console.log(e);
req.flash(e.message);
res.redirect("back");
}
};
Here's another alternative without async/await that just attempts to consolidate the error handling a bit. You can't get around the fact that there are three if checks and four possible errors:
middlewareObj.checkCampground = (req,res,next) => {
function error(msg, location = "back") {
req.flash(msg);
res.redirect(location);
}
if(req.isAuthenticated()) {
error("You need to be logged in to do that");
return;
}
Campground.findById(req.params.id).then(foundCampground => {
if (!foundCampground) {
error("Campground not found");
} else if (foundCampground.author.id.equals(req.user._id) || req.user.isAdmin) {
next();
} else {
error("You don't have permission to do that");
}
}).catch(err => {
console.log(err);
error("Database Error - Campground not found");
});
};
Note that in both of these, I make sure and log an actual database error if there is one.
my database look like this
users(collection)
user_id(document)
images(collection)
image_id(document)
i used collectionGroup to reach all images collection and now i want get the image by id.
Firestore.instance.collectionGroup('images').document('$imageid').get().then((onValue){
but with collectionGroup() there's no document()
In Swift language, I would go like this:
// (tested and confirmed)
Firestore.firestore().collectionGroup("users").getDocuments { (doc, err) in
if err != nil {
print(err?.localizedDescription)
}
if doc?.isEmpty == false {
for doc in doc!.documents {
print("DOC = ", doc.documentID)
}
}
}
I don't use Dart, but I found this online for you. You might have to tweak it so it compiles for you. I know it's using collection instead of collectionGroup.
final collRef = Firestore.instance.collection('images');
DocumentReferance docReferance = collRef.document();
docReferance.setData(map).then((doc) {
print('hop ${docReferance.documentID}');
}).catchError((error) {
print(error);
});
]
I know this question has been asked in the past but, I am unable to find a solution that works for swift 3. Could someone please point me in the right direction. Here is my code:
ref.child(uid).child("flights").observe(.value, with:{ (snapshot: FIRDataSnapshot!) -> Void in
self.messages.append(snapshot)
let row = [IndexPath(row: self.messages.count-1, section: 0) ]
print(snapshot)
self.flightTableView.insertRows(at: row, with: .automatic)
DispatchQueue.main.async {
self.flightTableView.reloadData()
}
})
}
I broke the code up into two statements and it started to work.
let child:FIRDatabaseReference = ref.child(uid).child("flights")
child.observe(.childAdded) { (snapshot:FIRDataSnapshot) in
print(snapshot)
}
Swift 3 & Firebase 3.17.0
This will do the trick, try this code
let ref = FIRDatabase.database().reference().child("uid").child("flights")
ref.observe(.value, with: { (snapshot) in
print("Success get the snapshot \(snapshot)")
// do something with snapshot than
DispatchQueue.main.async {
self.yourTableView.reloadData()
}
}) { (error) in
print("Failed get the snapshot \(error.localizedDescription)")
// do something to handle error
}