So, I have been coming across a problem where my Firebase app does not update user values when a user makes an update. To be more clear: Lets say user 1 has a photo of a dog and then changes it to a cat.
Once they change it to a cat, my node value in Firebase is successfully updated but the user themselves won't be able to see the change in other previously loaded areas in the app (other places with the dog picture) until they log out and then log back in.
For this reason I was wondering if there was any way to conduct a background app refresh that way all previous dog values in the app are changed to cat values without the user having to log out and then log back in. Please note that this same problem occurs not only with my user's profile picture but also any other user field I have setup.
Here is how I am updating a node value for my user in Firebase:
let storageRef = FIRStorage.storage().reference()
_ = FIRStorageMetadata()
let filePath = "\(FIRAuth.auth()?.currentUser?.uid)/\("userPhoto")"
let profileImageData = UIImageJPEGRepresentation(self.profilePicture.image!, 1.0)
if let data = profileImageData {
storageRef.child(filePath).put(data, metadata: nil){(metaData,error) in
if let error = error {
print(error.localizedDescription)
return
} else {
let downloadURL = metaData!.downloadURL()!.absoluteString
let userPhotoUpdateRef = FIRDatabase.database().reference().child("users").child(self.currentUser).child("userPhoto")
userPhotoUpdateRef.setValue(downloadURL)
}
}
}
If you have any questions please ask! Any help would be appreciated!
The Firebase SDK for Cloud Storage provides an easy way to read file from and write files to cloud storage. It does not provide a way to monitor those files.
The easiest way to provide a monitoring approach is to write the metadata of the files to the Firebase Realtime Database. See this short section in the Storage docs for a brief mention of that: https://firebase.google.com/docs/storage/ios/file-metadata#custom_metadata
When you write data to a location in the Firebase Database, all apps that are actively monitoring that location will be instantly updated. When they get that update, you can reload the image from Cloud Storage for Firebase.
Related
I have a simple iOS app that part of the app grabs all the users from firebase database so you can search them, and do different functions. Now my question is, if/when the app grows and there are thousands of users, does pulling all the users from the database and adding them to an array of [user]'s, still not crash or slow the app? I see so many people on youtube just loop through firebase and grab all the users. Please note I am excluding profile photos so there is no downloading images involved, just strings. I have some code I thought could solve this possible problem, but I am starting to wonder if there even is a problem with just fetching all the users from firebase and putting them into and array and then displayed in a tableview.
Here is some of my code right now, but it still I notice when I type in one letter, then turn airplane mode on, it downloaded all the users. I really need some help or some advice on this one, thanks.
var checklers = [String]()
func updateSearchResults(for searchController: UISearchController) {
if searchController.searchBar.text == "" {
filteredUsers = users
}
else {
print("refreshing")
if let uidi = FIRAuth.auth()?.currentUser?.uid {
view.addSubview(activityInd)
activityInd.startAnimating()
filteredUsers.removeAll()
checklers.removeAll()
let ref = FIRDatabase.database().reference()
ref.child("users").queryOrderedByKey().observe(.value, with: { snapshot in
if let userr = snapshot.value as? [String : AnyObject] {
for (_, velt) in userr {
if let usernamerr = velt["Username"] as? String {
if usernamerr.lowercased().contains(searchController.searchBar.text!.lowercased()) {
let userNew = usera()
if let name = velt["Full Name"] as? String, let uidd = velt["uid"] as? String {
userNew.name = name
userNew.username = usernamerr
userNew.uid = uidd
if self.checklers.contains(uidd) {
print("already")
}
else {
if userNew.uid != uidi {
self.filteredUsers.append(userNew)
self.activityInd.stopAnimating()
self.checklers.append(uidd)
}
print("added a user")
}
}
}
}
self.tableViewSearchUser.reloadData()
}
}
})
ref.removeAllObservers()
}
// filteredUsers = users.filter( { ($0.username?.lowercased().contains(searchController.searchBar.text!.lowercased()))! })
}
tableViewSearchUser.reloadData()
}
Please add any advice, thanks.
Just for searching one or two users, each time a user would need to fetch all the records and putting them all in an array (all in memory). You want SQL-where query function, but Firebase is just different and doesn't have it.
Problem with storing fetching all data approach:
1) Storing just all the user's information in an array of user objects is NOT scalable on client's device.
2) When the number of users gets to ten of thousands, a day worth of search by a single user will eat up a sizable amount of real time database read quota.
3) Stale user data, an user has to re-download all the users just becauase on user changed his name to Doggie1 to doggieTwo.
Solutions:
1) If you haven't done so already, I suggest the options of doing some server-side filtering first by following the best practice here:
Firebase Retrieving Data - Filtering
Downloading a sub-set of user that fits some criteria and then do a bit of client-side filtering. Still is problematic when users get to tens of thousands.
Firebase has a client-size data persistence feature, but in your case if there filtering rule doesn't fit your need, you need do you own caching with some persistent storage solution. Instead of putting the fetched object in an Array[User], I would store each in a database SQLite on iOS and Android apps.
2) Implement a ElasticSearch with the FlashLight plugin, this involves some extra setup (I know, I've been through it, I learned quite a bit), but it is well worth it for autocomplete and search functions that Firebase currently doesn't support.
A pluggable integration with ElasticSearch to provide advanced content searches in Firebase.
I need to show progress while uploading/downloading data from Firebase database.
Can I get it?. I saw in Firebase storage but I didn't saw in Firebase database.
Progress based on data:
I recommend looking over this post, as it will help you understand how to use some of the built in data references to determine your upload progress. While it is not for iOS, it explains the thought process of how you can measure upload progress.
You can always use a progress monitor like such:
let observer = uploadTask.observeStatus(.Progress) { snapshot in
print(snapshot.progress) // NSProgress object
}
Progress based on count:
As to what FrankvanPuffelen said, there is in fact no tool to give you what you are asking for. However, as Jay states, you can determine the "progress" of your task(s) based on how you are reading/writing.
Say for instance you are writing (uploading) 10 photos. For each photo that is successfully written (uploaded), you can simply increment some sort of progress meter by 1/10.
Example for some local file on the users device:
// Some image on the device
let localFile = URL(string: "<PATH>")!
// Make a reference to the file that needs to be uploaded
let riversRef = storageRef.child("chicken.jpg")
// Upload the file to the path you specified
let uploadTask = riversRef.putFile(from: localFile, metadata: nil) { metadata, error in
if let error = error {
// Whoops, something went wrong :(
}
else {
// Tada! Uploaded file
someCountVariable += 1
// If needed / applicable
// let downloadURL = metadata!.downloadURL()
}
}
Of course for one (1) item you will go from 0 to 100 (..real quick - shout out to Drake), but this can just be nested in some loop that iterates through some list of items to upload. Then per each item successfully uploaded increment.
This will be more expensive in terms of requests if you need to upload objects other than multiple images, but for the purpose this will give you a nice visual / numeric way of tracking at least how many items are left to be successfully uploaded.
If you really want to get down to the nitty gritty, you can always try checking the current connection strength to determine a relative data transfer speed, and cross that with the current task you are attempting. This could potentially give you at least some estimate the progress based on how long the process should take to how long it actually has taken.
Hope some of this helps / points you in the right direction. Happy coding!
val bytesTransferred=taskSnapshot.bytesTransferred.toFloat()
val totalByteCount=taskSnapshot.totalByteCount.toFloat()
val progress = bytesTransferred / totalByteCount
Log.d("progress", (progress*100).toString())
Log.d("progressDivide", (bytesTransferred / totalByteCount).toString())
Log.d("progressbytesTransferred", bytesTransferred.toString())
Log.d("progresstotalByteCount", totalByteCount.toString())
I’m using Firebase with the offline ability set to true.
let ref = FIRDatabase.database().referenceWithPath(“my data”).child(“my users id”)
scoresRef.keepSynced(true)
This path also has keep Synced set to true, as with out this with changes in the database are not seen within the app immediately as it is using the local cache.
I have another top level node / path in my app that I want to search - containing other users.
I want to use a singleEvent query and find an email address, I’m doing this via
studios.queryOrderedByChild("email").queryEqualToValue(email).observeSingleEventOfType(.Value, withBlock: { snapshot in // etc
I am able to find the node, however I keep getting the local cached version and not the most recent one in the firebase online store.
If I make some changes to the node online, I don’t get these back within the fetch.
If I changed my fetch to a monitor type i.e.
studios.queryOrderedByChild("email").queryEqualToValue(email).observeEventType(.Value, withBlock: { snapshot in // etc
I get the local cache node first, then get the online updated version as well.
I would rather use the SingleEvent fetch, but I don’t want to monitor the users entire node with keepSynced as it is a high level node and I don’t want to keep all that data locally, as its not directly related to the user.
One fix I found was prior to the single query was add .keepSynced(true) and in the completion block add .keepSynced(false). I'm not sure how much of the node is downloaded this was and may as well use the monitor fetch rather than the singleEvent.
Should I just use the monitorEvent or is there a better way to use SingleEventFetch that goes to the online store and instead of just returning my local node.
PS I am online and this is confirmed via
var connectedRef = FIRDatabase.database().referenceWithPath(".info/connected")
connectedRef.observeEventType(.Value, withBlock: { snapshot in
let connected = snapshot.value as? Bool
if connected != nil && connected! {
println("Connected")
} else {
println("Not connected")
}
})
Thanks
I am inserting a new contact with Apple's Contacts framework. The image is a .png from Asset catalog. After the successful insertion the new contact is visible with the correct image in the Contacts app. However, when there is an incoming call from the newly inserted contact the image is NOT displayed.
I couldn't find any reliable information about the exact cases when does the iOS display the contact image. Is it true that images will only appear if the user sets it manually? Did I miss something? Could you please point me to a good documentation or provide me an explanation? (The only relevant information is in this article: https://support.apple.com/en-us/HT202158 but I fulfill every requirement and it is probably not closely related.)
Code for the contact insertion:
let newContact = CNMutableContact()
...
if let image = UIImage(named: "ContactImage") {
newContact.imageData = UIImagePNGRepresentation(image)
}
...
let saveRequest = CNSaveRequest()
saveRequest.addContact(newContact, toContainerWithIdentifier: nil)
do {
try contactStore.executeSaveRequest(saveRequest)
log.debug("New contact successfully saved!")
} catch let error as NSError {
log.error(error.localizedDescription)
} catch {
log.error("Unknown error happened during contact saving.")
}
I've contacted Apple Developer Technical Support and their engineers determined that this would be best handled as a bug report. The submitted bug's ID is 26033574.
UPDATE
Apple asked me the following question.
Can you please share the vcard and image you’re using on the contact card?
I shared the vCard with them and unfortunately there was no image in it, although on iOS (and macOS) the image was clearly visible.
I found that saving the contact two times in a row solved the problem.
Save the contact
Add the image to the contact
Resave the contact
What I am trying to do is to save videos to PHPhotoLibrary, and then remove them when upload to clients remote server in the application completes (basically, photo library serves as temporary storage to add additional layer of security in case anything at all fails (I already save my vides it in the applications directory).
Problem:
The problem is for that to work, everything has to work without input from the user. You can write video to photos library like this:
func storeVideoToLibraryForUpload(upload : SMUpload) {
if PHPhotoLibrary.authorizationStatus() != PHAuthorizationStatus.Authorized {
// Don't write to library since this is disallowed by user
return
}
PHPhotoLibrary.sharedPhotoLibrary().performChanges({ () -> Void in
// Write asset
let assetRequest = PHAssetChangeRequest.creationRequestForAssetFromVideoAtFileURL(NSURL(fileURLWithPath: upload.nonsecureFilePath!)!)
let assetPlaceholder = assetRequest.placeholderForCreatedAsset
let localIdentifier = assetPlaceholder.localIdentifier
// Store local identifier for later use
upload.localAssetIdentifier = localIdentifier
}, completionHandler: { (success, error) -> Void in
....
})
}
And that works flawlessly, I get local identifier, I store it for later use.. Unicorns and rainbows.
Now when I want to remove that video immediately after upload finishes, I call following:
func removeVideoFromLibraryForUpload(upload : SMUpload) {
// Only proceed if there is asset identifier (video previously stored)
if let assetIdentifier = upload.localAssetIdentifier {
// Find asset that we previously stored
let assets = PHAsset.fetchAssetsWithLocalIdentifiers([assetIdentifier], options: PHFetchOptions())
// Fetch asset, if found, delete it
if let fetchedAssets = assets.firstObject as? PHAsset {
PHPhotoLibrary.sharedPhotoLibrary().performChanges({ () -> Void in
// Delete asset
PHAssetChangeRequest.deleteAssets([fetchedAssets])
}, completionHandler: { (success, error) -> Void in
...
})
}
}
}
Which successfully deletes the video, BUT user have to confirm deletion first. That is a problem as that backing up won't work.
I obviously know why there is confirmation (so you don't clear entire user library for example, but the thing is, My app made the video - and so I thought there will be way around it, since as an "owner" I should not be doing that, or at least have option to disable confirmation.
Thanks in advance!
TLDR: How can I disable confirmation on delete request, if my application created that content? (I don't want to delete anything else).
Note: Somebody can probably say this is rather strange thing to do but the application is distributed internally and there is good reason to do it like this (the video content is too valuable to be lost, even if user deletes the application for some reason, or there is anything at all that goes wrong, we need to be able to preserve the videos), so please don't question that and just focus your attention on the question :)
I cannot see a way to avoid the delete confirmation. It is an implementation detail of the Photos framework, similar to the way you cannot prevent the device from asking the user's permission to use the microphone when your app tries to use it, and is a matter of security & trust. Once you have saved an asset to the device photo library your app is no longer the owner of that asset, so as you noted in your question the device must of course ensure the app has the user's permission before it goes about deleting such data.
You can never entirely safeguard your users' data against their own unpredictable behaviour - if they decide to remove your app, or delete a particular asset from within Photos, it is up to them. I think your best option is to either put up with the built-in delete confirmation, or to provide a guide to your users that makes it clear that they should be careful to protect this important data by backing up their device, and not deleting the app!
If you did decide to stick to this approach, perhaps the best thing you could do is to prepare the user for the fact that their device may ask them for confirmation to delete a file that is being uploaded to your own servers. For example, put up your own modal alert just before trying to delete the asset. I wouldn't normally suggest that kind of approach for a public shipping app, but since you're only distributing internally it may be acceptable for your team.