carp_firebase_backend

Description:

carp firebase backend

CARP Firebase Data Backend #
A Flutter plugin for uploading data from the CARP Mobile Sensing Framework
to a Google Firebase data backend.
Supports uploading json to Firebase as either (zipped) files to Firebase Storage or as plain json to a Firebase Database.

For Flutter plugins for other CARP products, see CARP Mobile Sensing in Flutter.
This package can upload sending data to Goggle Firebase in two ways:


Google Firebase Storage – By using the Google Firebase Storage endpoint, CARP sensing data are uploaded as raw or zipped JSON file, generated using the
FileDataManager
in carp_mobile_sensing.
In Firebase, files with sensed data is stored in the path specified in the FirebaseStorageDataEndPoint plus subfolders for each study and device.
The path on Firebase hence follow this pattern: /<path>/<study_id>/<device_id>/


Google Firebase Database – By using the Google Firebase Database endpoint, CARP sensing data are uploaded as raw JSON data points,
using Firebase as a DataManager in carp_mobile_sensing.
In Firebase, data json objects are stores in the collection specified in the FirebaseDatabaseDataManager.
JSON objects will be stored in collections named /<collection>/<study_id>/<device_id>/upload/<data_type>
relative to this path. For example, if collection is carp_data, study_id is 1234 and device_id is R16NW,
location data will be stored as documents in this collection: carp_data/1234/R16NW/upload/location.


Setting up support for Google Firebase #
For Firebase to work with your Flutter app, configuration of both Firebase and your Flutter app has to be done.
Please follow the step below in details, since the level of debugging / error messages are quite limited
when setting this up. If you are new to Firebase, then please start by reading the extensive
Firebase documentation first.
Then read the Add Firebase to your Flutter app tutorial.
Step 1: Configure Google Firebase #

Create a Firebase project with a cloud storage
Add Firebase to your Flutter project by following the description.
Note that you need to add support for both the Android and iOS version of the Flutter app.
Configure authentication

carp_firebase_backend supports two types of authentication:

username/password authentication
Google Sign-In on Android.
Note: SHA-1 information is required by Google Sign-In




Add users that can upload data e.g. via the console
Set up your storage security rules as shown below.

# Default access rule
service firebase.storage {
match /b/{bucket}/o {
match /{allPaths=**} {
allow read, write: if request.auth != null;
}
}
}
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For testing/debugging purposes, you may remove authentication by the authentication rule below (but should be removed
in production)
# No authentication rule
service firebase.storage {
match /b/{bucket}/o {
match /{allPaths=**} {
allow read, write;
}
}
}
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Step 2: Configure your app to use Firebase #
Follow the direction on how to configure a Flutter app to use Firebase.
On iOS

Add your app to your Firebase project. Enter your app’s bundle ID in the iOS bundle ID field.
Download the GoogleService-Info.plist file to obtain your Firebase iOS config file.
Using XCode, move the file into the Runner/Runner directory of your Flutter app.
Google services use CocoaPods to install and manage dependencies. Open a terminal window
and navigate to the location of the Xcode project for your app. The type

$ pod init
§ pod install
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This should install all the necessary pods for Firebase.

Note: It seems like Firebase is putting constraints on the naming of the iOS Bundle Name.
Even though a valid iOS bundle name can contain . (dots) and spaces, Firebase throws the following exception:

Terminating app due to uncaught exception 'com.firebase.core', reason: 'App name can only contain alphanumeric, hyphen (-), and underscore (_) characters'
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if dots are used. Hence, avoid using dots, but use - (hypen) instead. This is specified in the `ios/Runner/info.plist' file:
<key>CFBundleName</key>
<string>your-app-name</string>
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Note – it seems like adding Firebase support to your iOS app dramatically increases the Xcode build
process for the Flutter app. So – have patience...
On Android


Add your app to your Firebase project. Enter your app’s application ID in the Android package name field.


Download the configuration file named google-services.json
and make sure to put in in your Android app module root directory, i.e a folder like <appname>/android/app/


Add support for the Google Services Gradle plugin
to read the google-services.json file that was generated by Firebase.

in your IDE, open android/app/build.gradle, and add the following line as the last line in the file:

apply plugin: 'com.google.gms.google-services'

In android/build.gradle, inside the buildscript tag, add a new dependency:

dependencies {
// ...
classpath 'com.google.gms:google-services:4.3.2' // new
}
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note the version of this SDK may chance - see Add Firebase to Your Android Project



Step 3: Use the CARP Firebase Backend in your Flutter App #
In Flutter, the carp_firebase_backend plugin is used to upload data from carp_mobile_sensing to a Firebase endpoint.
Add the carp_firebase_backend plugin to the pubspec.yaml file.
dependencies:
flutter:
sdk: flutter
carp_firebase_backend: ^0.5.0 # support for uploading CARP data to Firebase
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Run flutter packages get. For more information on managing packages and plugins,
see Using Packages.
Using the Plugin #
Upload of files to Firebase Storage uses the FirebaseStorageDataManager and
upload of json objects to Firebase Database uses FirebaseDatabaseDataManager.
Using the library takes three steps.
1. Register the Data Managers #
First you should register the data manager you want to use (or both) in the DataManagerRegistry.
DataManagerRegistry().register(DataEndPointType.FIREBASE_STORAGE, new FirebaseStorageDataManager());
DataManagerRegistry().register(DataEndPointType.FIREBASE_DATABASE, new FirebaseDatabaseDataManager());
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2. Specify Access Details to the Firebase App #
Both data managers uses a FirebaseEndPoint object to handle access to Firebase.
In this object, Firebase endpoint configuration keys are stored as well as authentication details.
All of the Firebase configuration keys can be found in the Projects Settings in the Firebase Console.
Remember to register your app in Firebase, as described above.
The firebaseAuthenticationMethod key specify the authentication method. Currently, only email/password and
Google Sign-In is implemented (even though FireBaseAuthenticationMethods lists them all (for future use)).
Using email/password as authentication
final FirebaseEndPoint firebaseEndPoint = new FirebaseEndPoint(
name: "Flutter Sensing Sandbox",
uri: 'gs://flutter-sensing-sandbox.appspot.com',
projectID: 'flutter-sensing-sandbox',
webAPIKey: 'AIzaSyCGy6MeHkiv5XkBtMcMbtgGYOpf6ntNVE4',
gcmSenderID: '201621881872',
androidGoogleAppID: '1:201621881872:android:8e84e7ccfc85e121',
iOSGoogleAppID: '1:159623150305:ios:4a213ef3dbd8997b',
firebaseAuthenticationMethod: FireBaseAuthenticationMethods.PASSWORD,
email: "[email protected]",
password: "some_password");
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Using Google Sign-In as authentication
final FirebaseEndPoint firebaseEndPoint = new FirebaseEndPoint(
name: "Flutter Sensing Sandbox",
uri: 'gs://flutter-sensing-sandbox.appspot.com',
projectID: 'flutter-sensing-sandbox',
webAPIKey: 'AIzaSyCGy6MeHkiv5XkBtMcMbtgGYOpf6ntNVE4',
gcmSenderID: '201621881872',
androidGoogleAppID: '1:201621881872:android:8e84e7ccfc85e121',
iOSGoogleAppID: '1:159623150305:ios:4a213ef3dbd8997b',
firebaseAuthenticationMethod: FireBaseAuthenticationMethods.GOOGLE);
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3. Create the Data Endpoint #
Finally, you create the data endpoint (FirebaseStorageDataEndPoint or FirebaseDatabaseDataEndPoint) providing it
with a FirebaseEndPoint and add it as your Study data endpoint.
Firebase Storage Endpoint
final FirebaseStorageDataEndPoint storageEndPoint = new FirebaseStorageDataEndPoint(
firebaseEndPoint,
path: 'sensing/data',
bufferSize: 500 * 1000,
zip: true,
encrypt: false);

CAMSStudyProtocol study = CAMSStudyProtocol()..dataEndPoint = storageEndPoint;
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Note that a FirebaseStorageDataEndPoint extends the FileDataEndPoint class and parameters related to
how to create the files can be specified, including bufferSize, zip, and encrypt.
In the example above, the file buffer size is set to 1 MB, which is zipped before upload.
Firebase Database Endpoint
final FirebaseDatabaseDataEndPoint databaseEndPoint =
new FirebaseDatabaseDataEndPoint(firebaseEndPoint, collection: 'carp_data');


CAMSStudyProtocol study = CAMSStudyProtocol()..dataEndPoint = databaseEndPoint;
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Features and bugs #
Please file feature requests and bug reports at the issue tracker.
License #
This software is copyright (c) Copenhagen Center for Health Technology (CACHET)
at the Technical University of Denmark (DTU).
This software is available 'as-is' under a MIT license.