I am currently working with Firebase Firestore in an iOS application. There is a legal use case where users have to first accept a consent before I am allowed to upload their data to Firebase but I have the need to let users can already save data even if they have not yet agreed to the consent.
My question would be if it is possible to have two different instances of a Firestore database inside one iOS app. One instance that stores data only offline and does not sync and one which is syncing. Then I can decide at runtime where to store the data.
Is there any documentation or experience for this ?
It is definitely possible to access multiple Firestore databases (or other Firebase resources) in a single application. But only one of them can be initialized from the GoogleService-Info.plist. The other one(s) you will have to initialize from within your code, based on the information in the secondary GoogleService-Info.plist.
The basic approach for this is to first create a FirebaseOptions object with the configuration data of the second project:
// Configure with manual options.
let secondaryOptions = FirebaseOptions(googleAppID: "1:27992087142:ios:2a4732a34787067a", gcmSenderID: "27992087142")
secondaryOptions.bundleID = "com.google.firebase.devrel.FiroptionConfiguration"
secondaryOptions.apiKey = "AIzaSyBicqfAZPvMgC7NZkjayUEsrepxuXzZDsk"
secondaryOptions.clientID = "27992087142-ola6qe637ulk8780vl8mo5vogegkm23n.apps.googleusercontent.com"
secondaryOptions.databaseURL = "https://myproject.firebaseio.com"
secondaryOptions.storageBucket = "myproject.appspot.com"
And then use that to initialize a secondary App object to get the Firebase service(s) you need:
// Configure an alternative FIRApp.
FirebaseApp.configure(name: "secondary", options: secondaryOptions)
// Retrieve a previous created named app.
guard let secondary = FirebaseApp.app(name: "secondary")
else { assert(false, "Could not retrieve secondary app") }
let secondaryDb = Firestore.firestore(app: secondary)
Also see:
The Firebase documentation on using multiple projects in your application.
We had a similar Situation with our app - A legal use case has come up that requires users to opt-in to storing data in the cloud. To that end, we need a storage solution that allows for some data to be stored locally only and some data that is synced to the cloud when the user opts-in. We thought of turning off Firestore network activity for offline data: Firestore.firestore().disableNetwork(completion: )
However, we contacted Google and their PM suggested that
Firestore is not a great offline-only database. It's designed for data that will eventually sync to the server. The offline features are meant to paper over temporary connectivity losses. Performance degrades as the number of pending write operations (aka offline writes) increases, and query performance on large offline datasets is pretty bad when compared to normal on-device mobile databases.
While they may be able to use the two-database workaround, I would generally recommend they just choose a totally different data store for their offline-only data. SQLite is the standard option, but there are many others.
Related
I'm working on an iOS app that connects with Firebase. I was wondering, if it's possible to have data that a user uploads only be accessible to him/her. The docs explained how to do this for Firebase storage, but I'm not sure how to create a similar effect for the database. Is it possible to do this, or will all data be public to all users?
Additionally, if it is possible to have the data only be accessible to the specific user, will the data still be visible to me in the database?
Thanks for your help.
What you are looking for is a concept called "security rules" with Firebase. Is it available with Realtime database and Firestore.
You can restrict access as you described and data remains available to you since you will be the administrator of the database.
I have an app where a UITableView is used to represent a friends list. Now, this table is updated by values stored in core data, and I'm downloading friend values to core data via Parse. Instead of accessing Parse to update the tableView directly, I decided to update Core Data and then the tableView because I need the friend information in other parts of the app, and thought it would be more efficient to use Core Data than to have calls to Parse again and again. Everything works fine!
However, my app has a log in system before users can use the app. And when I created another dummy user to test it, I found that the friend values stored in Core Data by my actual account were being used to update the friend list tableView! When actually the tableView should be empty (new user).
I don't know exactly how Core Data works but I figure it uses some segment of the device's memory to store entities. My question is this, is it possible to use Core Data to store private information related to a particular user that can't be accessed by other users that log into the same device? Or should I continue to make calls to Parse whenever I need information?
Hope you guys understood my question, thanks!
iOS is not a multi-user system. Your app stores its files in a sandboxed folder structure and this sandbox is independent of any user logins you have implemented in your app.
When a new user logs in (or, if you prefer, when a user logs out) it is up to you to remove any data you have stored in Core Data that you don't want another user to have access to.
Parse can save data offline by Local Storage or cache the request by Cache Policy
They are much faster than creating your own database (by CoreData).
As the header indicates, I am looking for the simplest way to sync user-generated data (Integers, Booleans, NSDates, etc) among a small number of individuals (at this point, I am just thinking of sharing data between two people). Within the app, users can populate an array with instances of a custom object and this data is used to populate a UITableview. Assuming all users in the select group have synced their devices they should all see the same data in the tableview.
My original idea was to write to a json file in a shared Dropbox or Google Drive folder. After looking around online, however, I found that this method is likely to lead to data corruption. Cloudkit only allows public or private (single account) syncing, nothing in between. I have seen some posts that recommend using Parse, but that service is now on its way out.
Does anyone know of a (preferably free) way to do this?
You have several options:
CloudKit databases - CloudKit's database system has the concept of a public database which does exactly what you want. It's fairly easy to use as well, and is "free" with an Apple developer account. The only downside is that it's for Apple devices only (AFAIK).
Firebase - Google's Firebase is basically identical to CloudKit in concept and features, but runs on multiple platforms. It is tied to the Google ecosystem, so your uses all need to provide a Google account to use it, but that's a small issue these days.
Realm - from a pure usability perspective, Realm is BY FAR the easiest data storage solution I've seen on iOS. However, it's sharing functionality is currently limited, CloudKit support is scheduled but currently all there is is this. If you only need local storage for now, then definitely keep this on your list.
No matter which engine you choose, users would be limited to certain views of the data through your own code. I would suggest that you save every record with a username of the creator, and then have another table containing read/write permissions, so for instance, the entry for "maurymarkowitz" has "bobsmith,ronsmith,jonsmith". You can retrieve these entries on login and then use them as the inputs to the query-by-example both systems use for getting records.
Thanks for all of the helpful responses. I ended up using cloudkit/coredata and it serves my purpose just fine. I simply used the public option and gave each set of users who are sharing data with each other a unique identifier, which is appended to any records they upload. When a user syncs their data with the cloud the application performs a query for only those records that contain the user's identifier. This way, multiple users can sync data among themselves even though they do not share an iCloud account.
I am looking for the proper way for a swift iOS app that relies on, in my case: AWS but has a local persistent data store so that every possible feature of the app can be used offline.
So far, I went from a pillar or two of Core Data to a full core data stack and it is becoming difficult to foresee how to coexist with AWS DynamoDB. While DynamoDB is of a NoSQL structure, Core Data in the way I have set it up is that of a SQLite persistent data store.
I need to eventually download tables and primarily use AWS for most situations where users are online, but if they want to work offline, I need to be prepared. Perhaps I should try to create a singular User entity, because why would I want to store other users offline? Then once internet is active, I could try to push it to my DynamoDB Users (plural) table.
I have created Entity's in Core Data such as Users, Authors, Profile.
In the scenario a user opens the app and has no internet access, I am planning on inserting a Users entity and my goal is to correctly populate Authors and Profile, because this offline end user is definitely a User, and I want to setup at least a Profile for them as well so that they can later tweak with customizations.
I have maybe too many relationships. I want to do this correct.
In simple situations, I understand a Person Entity might have a father, mother, child and how they can all fit nicely into Person, but since I have entities with enough unique attributes that I thought I need to create their own entities,
How should I go about creating an entity that certainly makes a User/Users record and establishes a Profile?
Short answer is this:
Core Data is your local cache whether you are offline or online. If you are online then the app should refresh the Core Data cache when appropriate.
When offline the app should not update the cache.
The User Interface in either case is identical. The user interface feeds from the Core Data cache ONLY.
I suggest watching my talk on MVC-N that is hosted by realm.io.
I am about to build an internal-only iOS app for storing simple business data. The data store will consist of a single entity only, with one entry per day. To start with there will be around two years worth of data (~750 entries).
I want to set the app up to do one-way syncing only. i.e. Only one person can enter data, but others can read it. iCloud is out as it only works for a single user account.
Is there a lightweight way to sync this datastore out from the single write user to the other read users? Setting up a full sync system seems overkill for this case.
Instead of iCloud, you could use one of the online backends such as Parse.com or Simperium. They would allow you to share data using a db and also provide for user accounts, authentication etc. If you want to run the server locally you can investigate DataKit.