Develop Reference

How to add new fields in Firestore Document from two different sources simultaneously?

When a new user registers in my app using firebase-authentication custom sign in using email and password, I need to update that data into my firestore.
But Firebase only has FirebaseAuth.createUserWithEmailAndPassword(email, password) to create a new account and hence I cannot update my user's username at the same time.
To update the E-Mail in Firestore, I use Firebase cloud functions. Here's the code:
export const onNewUserJoined = functions.auth.user().onCreate((user) => {
//const newUserDisplayName = user.displayName //CAN'T USE THIS. REASON is BELOW
const newUserUID = user.uid
const newUserEmail = user.email
const timeCreated = Date.now()
console.log(`${newUserUID} has joined.`)
return admin.firestore().collection('Agent').doc(`${newUserUID}`).set({"E-Mail": newUserEmail, "Time": timeCreated})
})
OK, great now I have updated the E-Mail and time created in Firestore successfully.
But next challenge is I need to update the user's username in the same Firestore document. I do it instantly after the createUserWithEmailAndPassword() like this:
DocumentReference dDocRef = FirebaseFirestore.getInstance().document(documentPath);
Map<String, Object> updateUsernameAndPhone = new HashMap<>();
updateUsernameAndPhone.put("username", username);
updateUsernameAndPhone.put("phoneData", phoneModel);
dDocRef.update(updateUsernameAndPhone).addOnSuccessListener(new OnSuccessListener<Void>() {
#Override
public void onSuccess(Void aVoid) {
Toast.makeText(getApplicationContext(), "Data successfully stored in Firestore", Toast.LENGTH_SHORT).show();
}
}).addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
});
Now, it depends on who acts first, the cloud function or the user's device.
If the cloud functions act first, then there is no issue. The username and phoneModel both get updated into the document successfully. No issues.
But incase, the phone acts first then I get the following error:
As this error has occurred, username isn't in the document and only email and timeCreated are in the document updated by the cloud function which got late to create document so that user's device can update the username with ease.
I CAN'T use .SET instead of .update() in my app because if I use .set() and the cloud functions create the email and timeCreated fields first. Then the device will DELETE them and put username and phoneModel.
So how can I do this?
I can forcefully delay updating the username by putting it in the next activity so that cloud functions get enough time to do their job, but my signUpActivity asks for username along with email and password edit texts. I don't want to create a separate activity for that.
I used to use .update() when my data was stored in realtime database and it used to create the child even if the path didn't exist. But it looks firestore won't update if the field doesn't exist.
Any solution for this?
I tried as per #DougStevenson said and here's my code:
final String newUserUID = Objects.requireNonNull(signUpAuth.getCurrentUser()).getUid();
final String documentPath = "Agent/" + newUserUID;
FirebaseFirestore fFirestoreRef = FirebaseFirestore.getInstance();
final DocumentReference dDocRef = fFirestoreRef.document(documentPath);
fFirestoreRef.runTransaction(new Transaction.Function<Void>() {
#Nullable
#Override
public Void apply(#NonNull Transaction transaction) throws
FirebaseFirestoreException {
DocumentSnapshot documentSnapshot = transaction.get(dDocRef);
transaction.update(dDocRef, "username", username);
transaction.update(dDocRef, "phoneData", phoneModel);
return null;
}
}).addOnSuccessListener(new OnSuccessListener<Void>() {
#Override
public void onSuccess(Void aVoid) {
Toast.makeText(getApplicationContext(), "Data updated in Firestore . . .", Toast.LENGTH_SHORT).show();
}
}).addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
});
But no luck. It still gives me error: Cannot update a document which does not exist.

Use a transaction to resolve conflicts from multiple clients that are all trying to modify the same document. The transaction handler will be retried on the client if it detects the document was modified before the change could take place.

how to know if a valid FirebaseAuth is going to expire soon

I've a weird behavior in my app related to the firebase database.
I got some unexpected access denied when trying to perform some stuff at database... That could be bug in my code but is a pretty simple code.
I want to ilustrate the sitation with a real scenario, please read the requirements
1- i've only 1 app accessing the database (android)
2- i've only 1 method in the whole app trying to access the specific node which is causing deny of access
3- in my firebase rules the only rule applied to this node is:
".read":"auth != null",
".write":"auth != null"
4- i DO explicity check FirebaseAuth.getInstance().getCurrentUser() != null right before calling the method
this is a pseudo snippet of how my code is (i wont pust the real code simple because is too long)
public void onResume() {
if(FirebaseAuth.getInstance().getCurrentUser() == null)
doLogin();
else
checkFirebaseStuff();
}
As google doesn't provide any info about why the access was rejected the only possible explanation i found is:
the user was authenticated but long time before, so when it checked on if was still valid, but short time later when the function really ran its token (or some other firebase auth check) was no longer valid, so it caused the access denied
this error doesn't happen a lot, i have 5k daily users and it happens around 20 or 50 times a day, but still shouldn't happen even once
does it make sense? can anyone help me with any aditional info?

Hmm, I think you can fix this by checking if the user is disconnected from the firebase database, but I'm not really sure if that will affect the Auth too, you can give it a try
DatabaseReference connectedRef = FirebaseDatabase.getInstance().getReference(".info/connected");
connectedRef.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
boolean connected = snapshot.getValue(Boolean.class);
if (connected) {
Log.d(TAG, "connected");
//Here you can update your mAuth state
} else {
Log.d(TAG, "not connected");
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
Log.w(TAG, "Listener was cancelled");
}
});

Firebase : What happens to a database connection after it has been used

I was just wondering if there isn't a need to close the FirebaseDatabase.getInstance() instance after it has been used or free whatever resources used by this.
I use the instance as follows.
String UID = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference DB = FirebaseDatabase.getInstance().getReference();
for (final Message M : Messages) {
if (!M.getSender().equals(UID) && !M.getLocal() && !M.getRead()) {
DatabaseReference r = DB.child("chat/messages/" + M.getMessageid()+"/read");
r.setValue(true, new DatabaseReference.CompletionListener() {
#Override
public void onComplete(DatabaseError e, DatabaseReference dbr) {
if (e != null) {
System.out.println("Message Read could not be updated" + e.getMessage());
} else {
System.out.println("Message Read updated" + M.getMessageid());
}
}
});
}
}

When you first start interacting with the Firebase Database, it opens a socket connection between the app and the Firebase servers. From that moment on, all traffic between the app and the database goes over that same socket.
If there are no active listeners and no write operations for a certain amount of time, the Firebase Database client will automatically close the connection. Of course it will then re-open the connection when you attach a listener or perform a write again.
If you want more fine-grained control over the connection, you can explicitly manage this by calling goOffline() and goOnline(). See https://firebase.google.com/docs/database/android/offline-capabilities#section-connection-state

How to know which user is trying to Sign-in?

Users are created using Email and Password. This is how I do the Sign-up:
mSignup.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mEmailStr = removeSpaces(mEmail.getText().toString());
mPasswordStr = mPassword.getText().toString();
mUsernameStr = mUsername.getText().toString();
mIsSgl = mSglCheckBox.isChecked();
mUsernameStr=mUsername.getText().toString();
final User mUser = new User();
mUser.setEmail(mEmailStr);
mUser.setPassword(mPasswordStr);
mUser.setIsSgl(mIsSgl);
mUser.setStudyGroupName(mStudyGroupName);
mUser.setUsername(mUsernameStr);
FirebaseAuth.getInstance().createUserWithEmailAndPassword(mUser.getEmail(), mUser.getPassword()).addOnCompleteListener(new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(Task<AuthResult> task) {
if (task.isSuccessful()) {
Toast.makeText(getActivity(), "Sucsses", Toast.LENGTH_SHORT).show();
generateUser(mUser);
startActivity(new Intent(getActivity(), MainActivity.class));
} else {
Toast.makeText(getActivity(), "not Sucsses", Toast.LENGTH_SHORT).show();
}
}
});
}
});
This is how I push the data into database:
public void generateUser(User user)
{
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference users;
if(user.getIsSgl())
{
users = database.getReference(user.getStudyGroupName()).child("SGL");
}
else
{
users = database.getReference(user.getStudyGroupName()).child("Student");
}
users.push().setValue(user);
}
This is how I Sign-in:
mSignin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mEmailStr = SignupActivityFragment.removeSpaces(mEmail.getText().toString());
mPasswordStr = mPassword.getText().toString();
mAuth.signInWithEmailAndPassword(mEmailStr, mPasswordStr).addOnCompleteListener(getActivity(), new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(Task<AuthResult> task) {
if (task.isSuccessful()){
FirebaseDatabase database = FirebaseDatabase.getInstance();
// thats not worked for me
database.getReference("StudyGroups").child("Student").orderByChild("email").equalTo(mEmailStr).addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot childSnapShot : dataSnapshot.getChildren()) {
userKey = childSnapShot.getKey();
}
Toast.makeText(getContext(),"Userkey: " + userKey,Toast.LENGTH_LONG).show();
Log.v("himaAbousalem",userKey);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
Toast.makeText(getActivity(), "Sucsses ", Toast.LENGTH_SHORT).show();
startActivity (new Intent(getActivity(),Controller.class));
}else {
Toast.makeText(getActivity(), "not sucsses", Toast.LENGTH_SHORT).show();
}
}
});
}
});
I want to query the database so that when a user signs-in by Email and password, it returns all the data of that user from the database.
How can I make the key of userId in Auth equal to the userId in database and how do I use that feature?

tl;dr - In this case, store each user using their associated uid generated by Fireabase Auth instead of using a push ID.
In your situation the challenge with using a push ID to store info specific to each user is that when a user signs in you don't know the push ID you used when you first stored their info. To find a user each time they sign in you would have to search through every user in your database until you find a matching email/password to retrieve their correct profile information - the more users you have, the longer it would take to do the search. One alternative, which would probably be faster, is to use Firebase Authentication to create users and the Firebase Database to store any user specific information.
When you create a new user using Firebase Authentication it will assign a unique user id to the user that will be the same throughout the lifetime of the user. You then use the unique user id generated by Firebase Auth instead of a push ID to store user info in the database. The next time a user signs in you get the user's uid from Firebase Auth and use it to query the database to get that user's information.
Check the guide for how to create a password-based user and how to sign a user in using Firebase Auth: Create a password-based account
In order to use the unique uid generated by Firebase Auth I suggest a few changes to your code.
Update database structure
I suggest you update your database structure by adding a new location (maybe "allUsers") for use when you create/sign in users. Right now it looks like your are breaking up students into groups. If you need to keep this structure, for reasons beyond authentication, you can use it along with my suggestion. The reason for a single location which stores all users is that you need a definite location to query when a user signs in. When using Firebase Auth, without a single location which stores all users there is no way to tell what group a user belongs to when they first sign in. You would have to check every group in order to find a match and that may take a long time. Having a location which stores all users solves that problem. Also, the query for retrieving user information from that single location is much simpler. If you do need to keep a user's information in multiple places just be sure to update their information in both places if any changes occur.
Create a class variable used to distinguish between create user and sign in existing user.
If you use the same Activity to create a new user and sign in an existing user then create a boolean variable to make a distinction between when a new user is being created and when an existing user is signing in. It will be used later in the AuthStateListener. If you handle user creation in a separate activity from general sign in then you shouldn't need this variable because each activity would have a separate AuthStateListener.
boolean mIsNewUser = false;
Move the call to generateUser() from the create user completion listener to an AuthStateListener. Also move your database query from the sign in completion listener to the AuthStateLisener
Whenever you create a user successfully they will automatically be signed in too. So, if you move your call to generateUser() from the createUserWithEmailAndPassword OnCompleteListener to your AuthStateListener you can get access to the created user's uid. When signing an existing user move your database query to the AuthStateListener as well, again so we can access the user's uid. I'm also going to create a helper method for the database query called getExistingUserInfo. As an FYI, the onComplete() callback in the OnCompleteListeners for creating and signing in users gives you access to an AuthResult which according to the API has a method for returning the current user but the documentation says to access user information in the AuthStateListener.
private FirebaseAuth mAuth;
private FirebaseAuth.AuthStateListener mAuthListener;
#Override
protected void onCreate(Bundle savedInstanceState) {
mAuth = FirebaseAuth.getInstance();
mAuthListener = new FirebaseAuth.AuthStateListener() {
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth firebaseAuth) {
FirebaseUser user = firebaseAuth.getCurrentUser();
if (user != null) {
// User is signed in
Log.d(TAG, "onAuthStateChanged:signed_in:" + user.getUid());
if(mIsNewUser){
//call to generate user using Uid instead of pushID
generateUser(mUser, user.getUid());
} else{
getExistingUserInfo(user.getUid());
}
startActivity(new Intent(getActivity(), MainActivity.class));
} else {
// User is signed out
Log.d(TAG, "onAuthStateChanged:signed_out");
}
// ...
}
};
// ...
}
}
#Override
public void onStart() {
super.onStart();
mAuth.addAuthStateListener(mAuthListener);
}
#Override
public void onStop() {
super.onStop();
if (mAuthListener != null) {
mAuth.removeAuthStateListener(mAuthListener);
}
}
Update your generateUser() helper method to use the uid instead of a push ID:
I'm going to assume you want to keep you existing database structure and add the single location for all users as suggested. Based on this I've made a couple of changes to the write operation you were using in generateUser(). Mainly, instead of using setValue() to write to the database I'm using updateChildren(). By using updateChildren() we can take advantage of Firebase's ability to do atomic updates. This will allow us to write to the appropriate student group location and the location storing all users simultaneously. By taking this approach if the write operation to either location fails neither location will be updated. This way you can be certain if a student is added to a group they will also be listed in the allUsers location.
private void generateUser(User user, String uid)
{
DatabaseReference database = FirebaseDatabase.getInstance().getReference();
String userType;
String allusers = "allUsers/" + uid;
Map<String, Object> newUserUpdate = new HashMap<>();
if (user.getUsername() != null) {
if (user.isSgl()) {
userType = user.getStudyGroupName() + "/" + "SGL" + "/" + uid;
} else {
userType = user.getStudyGroupName() + "/" + "Student" + "/" + uid;
}
newUserUpdate.put(userType, user.serialize());
newUserUpdate.put(allusers, user.serialize());
database.updateChildren(newUserUpdate);
}
}
Update database query to use new location which stores all users
As I mentioned above, by creating a single location for all users you can reduce the complexity of the query used to find a user's info when they sign in. Again, if you need to store users by group you can keep that but be sure to update both locations if a users info changes.
public void getExistingUserInfo(String uid){
FirebaseDatabase database = FirebaseDatabase.getInstance();
database.getReference("allUsers").child(uid).addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
//get user data from dataSnapshot
Toast.makeText(getContext(),"Userkey: " + userKey,Toast.LENGTH_LONG).show();
Log.v("himaAbousalem",userKey);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
Set the variable used to distinguish between existing user sign in and new user creation in the create user completion listener
FirebaseAuth.getInstance().createUserWithEmailAndPassword(mUser.getEmail(), mUser.getPassword()).addOnCompleteListener(new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(Task<AuthResult> task) {
if (task.isSuccessful()) {
//set boolean used in the AuthListener
mIsNewUser = true;
Toast.makeText(getActivity(), "Sucsses", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getActivity(), "not Sucsses", Toast.LENGTH_SHORT).show();
}
}
});

Data not getting saved in Firebase database from android

I am using the new Firebase console. I am trying to save an object to the database but its not getting saved. Following is the code.
DatabaseReference mFirebaseRef = FirebaseDatabase.getInstance().getReference();
mFirebaseRef.push().setValue(object, new DatabaseReference.CompletionListener() {
#Override
public void onComplete(DatabaseError databaseError, DatabaseReference reference) {
if (databaseError != null) {
Log.e(TAG, "Failed to write message", databaseError.toException());
}
}
});
the 'object' is created properly. There is no error I am getting and I have checked in debugging that the onComplete method is not getting triggered.
Security Rule is also true for write.

Note that DatabaseReference.CompletionListener fires "when an operation has been acknowledged by the Database servers". Is it possible you did not have a network connection at the time you ran your test? I copied your code and ran it successfully on a phone with object defined like this:
Object object = new String("Test");
I then enabled airplane mode, re-ran the code and observed the behavior you describe. The completion listener did not fire until I disabled airplane mode and a network connection was established.
Example code for checking the status of your network connection is provided in this documentation.

use the below code:
mFirebaseRef.push().setValue(object).addOnCompleteListener(new OnCompleteListener<Void>()
{
#Override
public void onComplete(#NonNull Task<Void> task) {
if(task.isSuccessful()){
// write code for successfull operation
}
}
});
}
.push will generate a random key on which your data will stored if you do not use .push it will overwrite on previous stored data.