PFUser currentUser returns nil - ios

I'm using Parse SDK, login and signup are working perfectly : [PFUser currentUser] is returning the current user.
But after restarting app, [PFUser currentUser] is returning nil.
Why is the application not persisting the session ?
Login code (from parse.com) I'm using :
[PFUser logInWithUsernameInBackground:self.username.text password:self.password.text
block:^(PFUser *user, NSError *error) {
if (user) {
// Do stuff after successful login.
} else {
// The login failed. Check error to see why.
}
}];
EDIT 2: Create new project, it works. I don't know how and why, but it works.
EDIT: There is no logoutin the whole project

It looks like you are calling .logout somewhere, in which case the app will return nil for [PFUser currentUser].
The current user will persist from session to session if you do not automatically log out the user.

PFUser *currentUser = [PFUser currentUser];
if (currentUser) {
//save the installation
PFInstallation *currentInstallation = [PFInstallation currentInstallation];
currentInstallation[#"installationUser"] = [[PFUser currentUser]objectId];
// here we add a column to the installation table and store the current user’s ID
// this way we can target specific users later
// while we’re at it, this is a good place to reset our app’s badge count
// you have to do this locally as well as on the parse server by updating
// the PFInstallation object
}

Related

How can two parse apps share PFObjects and link identities via PFUser?

I have an iPad-only app where some users (the ones who buy in-app purchases) have PFUser objects that are linked to their currentInstallation like this:
PFInstallation *currentInstallation = [PFInstallation currentInstallation];
if( [PFUser currentUser] != nil )
currentInstallation[#"user"] = [PFUser currentUser];
The identity behind the PFUser is the Facebook identity:
[PFFacebookUtils initializeFacebook];
[PFFacebookUtils logInWithPermissions:nil block:^(PFUser *user, NSError *error) {
if (!user) {
// Handle error path
failPath();
} else {
// Handle success path
[FBRequestConnection startForMeWithCompletionHandler:^(FBRequestConnection *connection, NSDictionary<FBGraphUser> *user, NSError *error) {
if (error) {
failPath();
} else {
// Save the name on Parse
[PFUser currentUser][kParseUserKeyFacebookName] = user.name;
[PFUser currentUser][kParseUserKeyFacebookID] = user.objectID;
[[PFUser currentUser] saveInBackgroundWithBlock:....
Now I want to release a new app for the iPhone, which acts as a kind of "admin console" for the iPad app. The iPhone app will receive push notifications when things go wrong on the iPad app etc (the iPad is in use by many people).
Question: On the new iPhone app, presuming I can get the user to log in with the same facebook ID, how can I correlate back to the same user's ipad data on parse? For example can I get the ipad app's PFObjects and/or PFUser data in the iphone now?
Concrete example: set a password on the ipad app, log into facebook on the iphone app, enter that same password. How to check it against the ipad app password, from the iphone?

Query PFInstallation and add to channels key from cloud code

I am trying to get subscriptions added to all PFInstallations for a particular PFUser (for cases of one person using same login on iPhone iPad, etc.). I have a table view of all their Facebook friends who use the app as well. On selecting the friend in row, I want it to get my objectId and query all PFInstallations to get an array of all the PFInstallations where the key usersObjectId matches the PFUser objectId. Then, I can add a value to the channels of each of those PFInstallations. I have:
FriendArray *job = self.jobsArray[indexPath.row];
PFQuery *query = [PFUser query];
//job.facebookid is the Facebook id for that particular user
//each PFUser has a fbId and for those who logged in with Facebook, their Facebook ID is stored here
[query whereKey:#"fbId" equalTo:job.facebookid];
PFUser *user = (PFUser *)[query getFirstObject];
//This gives me the PFUser whose fbId value matches the Facebook id for the row that was selected
NSString *subscription = [#"User_" stringByAppendingString:user.objectId];
PFUser *me = [PFUser currentUser];
PFQuery *pushQuery = [PFInstallation query];
//Trying to get all PFInstallations that match the current user's usersObjectId, so I can add the value to each channel
[pushQuery whereKey:#"usersObjectId" equalTo:[me objectId]];
PFInstallation *allInstallations = (PFInstallation *)[pushQuery findObjects];
[allInstallations addUniqueObject:subscription forKey:#"channels"];
It tells me, though, that PFInstallation cannot be directly queried. How can I do the same thing in cloud code?
Ok, after hours of work, I finally figured it out, and thought would post the solution. If you want to edit all your PFInstallation entries of a certain type (I do this by always putting my PFUser objectId as a new value on PFInstallation), here you go.
For cloud code use:
Parse.Cloud.define("subscribingAll", function(request, response) {
Parse.Cloud.useMasterKey();
var usersObjectId = request.params.usersObjectId;
  var newSubscription = request.params.newSubscription;
var pushQuery = new Parse.Query(Parse.Installation);
pushQuery.equalTo("usersObjectId", usersObjectId);
pushQuery.find({
success: function(results) {
response.success(results);
},
error: function() {
response.error("failed");
}
});
});
Then, on your app, you need a PFCloud call to handle all this.
[PFCloud callFunctionInBackground:#"subscribingAll"
withParameters:#{#"usersObjectId": [me objectId], #"newSubscription": subscription}
block:^(NSArray *theCount, NSError *error) {
if (!error) {
int i;
for (i = 0; i < [theCount count]; i++) {
PFInstallation *change = [theCount objectAtIndex:i];
[change addUniqueObject:subscription forKey:#"channels"];
[change saveInBackground];
}
}
}];
The cloud code returns an array where each object is the data from PFInstallation matching the query. You need to run this through a loop, and set each objectAtIndex as a PFInstallation. From there, just do a simple addUniqueObject, and voila, you are done.
In my case, when logging in, it duplicates the objectId to a key called usersObjectId that I made for PFInstallation. So, I login on my iPhone and then again on my iPad, I have 2 different PFInstallations but both with the same usersObjectId. Running all this code allows me to isolate all of my owned Installations and edit them, specifically to go along with the code I use for subscribing to Facebook friends, so that I can be notified when they post something.
It looks like you can only modify a PFInstallation on the current device, and not all from one user or in the cloud.
This is the code shown on parse :
PFInstallation *currentInstallation = [PFInstallation currentInstallation];
[currentInstallation addUniqueObject:#"Giants" forKey:#"channels"];
[currentInstallation saveInBackground];
Maybe a workaround could be adding a new default channel that you subscribe every user to that sends them a notification if they should subscribe to a new channel? I'm unsure if this is the best solution, as I do not know in what context you are performing this subscription.

Deleting user directly from cloud at Parse framework

I am using the following code at my application:didFinishLaunchingWithOptions: function,
[PFUser enableAutomaticUser];
[[PFUser currentUser] saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
if (succeeded && !error) {
[[UserContainer sharedUserContainer] addUser:[PFUser currentUser]];
}
}];
hoping that if the user was removed from the database, this would create a new user, or resurrect the previous user. This completes with no error and with succeeded = true, but there is no data at the cloud.
Is this expected or a bug? How should I handle recreating new anonymous users when the existing user is deleted?

Delete object from user class in Parse.com

I'm trying to delete the image connected to the current user from the imageOne column in Parse.com. From the user class.
PFQuery *query = [PFUser query];
[query selectKeys:#[#"imageOne"]];
[query getObjectInBackgroundWithId:[[PFUser currentUser] objectId] block:^(PFObject *object, NSError *error) {
if (!error) {
[object deleteInBackground];
}
}];
My code doesn't work and the console logs this error "User cannot be deleted unless they have been authenticated via logIn or signUp".
How can I fix this?
Seems like the problem comes from the fact that object (image) comes from the user class, am I right?
Why are you doing a query for all users and then doing the delete for just the current user, that's the worst possible way to structure the query (and most likely to fail).
If the current user isn't in the first 100 returned your above code would never find a match.
This sort of query should instead be done using getObjectInBackgroundWithId:block:, but in the case of the current user you already have the object, just do this:
[[PFUser currentUser] deleteInBackground];
If instead you just want to delete information in a column, use the following:
PFUser *currentUser = [PFUser currentUser];
[currentUser removeObjectForKey:#"imageOne"];
[currentUser saveInBackground];

Can't write non current user objects by PFUser currentuser

I would like write a PFUser object by the currentUser, i've added the ACL based on the Parse developer guide, but i still get an error:
'User cannot be saved unless they have been authenticated via logIn or signUp'
_ My code:
PFQuery *query = [PFUser query];
[query whereKey:#"username" equalTo:self.bBo];
PFObject *friendData = [query getFirstObject];
PFUser *user = (PFUser *)friendData;
PFACL *userACL = [PFACL ACL];
user.ACL = userACL;
[userACL setWriteAccess:YES forUser:[PFUser currentUser]];
PFRelation *friendRelation = [user relationforKey:#"array"];
[friendRelation addObject:[PFUser currentUser]];
[user saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
if (error){
NSLog(#"Error %# %#", error, [error userInfo]);
}
}];
I think i did everything correct, so i can't figure out what can be the problem. So if you made earlier something like this or know where is the problem, i would really appreciate any suggestions.
For security reasons, Parse won't allow you to save any changes to a user that is not currently logged in.
If you want to be able to make and save changes to user, you need to use Cloud Code and the Master Key to get around this roadblock.
I have had multiple problems like this before, and every time I've been forced to use a workaround via Cloud Code.
Here's an example of a workaround I did for creating a friends relationship between two users:
[PFCloud callFunction:#"editUser" withParameters:#{#"userId": user.objectId}];
The above code statement is in xcode, and executes the function I have added to my Cloud Code file.
Then, here's what my Cloud Code file looks like:
Parse.Cloud.define('editUser', function(request, response) {
var userId = request.params.userId;
var User = Parse.Object.extend('_User'),
user = new User({ objectId: userId });
var currentUser = request.user;
var relation = user.relation("friendsRelation");
relation.add(currentUser);
Parse.Cloud.useMasterKey();
user.save().then(function(user) {
response.success(user);
}, function(error) {
response.error(error)
});
});
The above code uses the Master Key to save changes to both the currently logged in user, and to the user who's objectId was passed into this function.
Code details:
var relation
This is just a variable I'm creating to hold what the following fucntion returns:
user.relation("friendsRelation");
In the above function, "friendsRelation" is the name of my PFRelation key in Parse.
Now that we have a valid relation object contain in our variable called relation, we execute this function with an argument of our currentUser object.
After that, all that's left is saving everything. I don't program with javascript, but I was still able to come up with the above solution by looking at the Parse Cloud Code docs, and searching around on their support forums.
If you take my template from above, and make some small changes, then you should be able to easily accomplish what you need. You just have to jump through these extra hoops because the Parse SDK doesn't want a situation where someone can login and somehow make changes to another user's account, whether by their own fault or a developer's mistake.
EDIT:
Here is the code to add the relationship for the current user:
PFRelation *friendsRelation = [[PFUser currentUser]relationforKey:#"friendsRelation"];
PFUser *user = [self.parseUsers objectAtIndex:indexPath.row];
[friendsRelation addObject:user];
[currentUser saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
if (error) {
NSLog(#"%# %#", error, [error userInfo]);
}
}];
And then you can call the Cloud Code method right after:
[PFCloud callFunction:#"editUser" withParameters:#{
#"userId": user.objectId
}];

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