If you've been working with Firebase on Android, you may have noticed that you don't normally have to write any lines of code to initialize a feature. You just grab the singleton object for that feature, and start using it right away. And, in the case of Firebase Crash Reporting, you don't even have to write any code at all for it to start capturing crashes! This question pops up from time to time, and I talked about it a bit at Google I/O 2016, but I'd also like to break it down in detail here.
The problem
Many SDKs need an Android Context to be able to do their work. This Context is the hook into the Android runtime that lets the SDK access app resources and assets, use system services, and register BroadcastReceivers. Many SDKs ask you to pass a Context into a static init method once, so they can hold and use that reference as long as the app process is alive. In order to get that Context at the time the app starts up, it's common for the developers of the SDK to ask you to pass that in a custom Application subclass like this:
public class MyApplication extends Application { @Override public void onCreate() { super.onCreate(); SomeSdk.init(this); // init some SDK, MyApplication is the Context } }
And if you hadn't already registered a custom subclass in your app, you'd also have to add that to your manifest in the application tag's android:name attribute:
<application android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:name="package.of.MyApplication" ... >
All this is fine, but Firebase SDKs make this a lot easier for its users!
The solution
There is a little trick that the Firebase SDKs for Android use to install a hook early in the process of an application launch cycle. It introduces a ContentProvider to implement both the timing and Context needed to initialize an SDK, but without requiring the app developer to write any code. A ContentProvider is a convenient choice for two reasons:
Let's investigate those two properties.
ContentProvider initializes early
When an Android app process is first started, there is well-defined order of operations:
When a ContentProvider is created, Android will call its onCreate method. This is where the Firebase SDK can get a hold of a Context, which it does by calling the getContext method. This Context is safe to hold on to indefinitely.
This is also a place that can be used to set up things that need to be active throughout the app's lifetime, such as ActivityLifecycleCallbacks (which are used by Firebase Analytics), or a UncaughtExceptionHandler (which is used by Firebase Crash Reporting). You might also initialize a dependency injection framework here.
ContentProviders participate in manifest merger
Manifest merge is a process that happens at build time when the Android build tools need to figure out the contents of the final manifest that defines your app. In your app's AndroidManifest.xml file, you declare all your application components, permissions, hardware requirements, and so on. But the final manifest that gets built into the APK contains all of those elements from all of the Android library projects that your app depends on.
It turns out that ContentProviders are merged into the final manifest as well. As a result, any Android library project can simply declare a ContentProvider in its own manifest, and that entry will end up in the app's final manifest. So, when you declare a dependency on Firebase Crash Reporting, the ContentProvider from its manifest is merged in your own app's manifest. This ensures that its onCreate is executed, without you having to write any code.
FirebaseInitProvider (surprise!) initializes your app
All apps using Firebase in some way will have a dependency on the firebase-common library. This library exposes FirebaseInitProvider, whose responsibility is to call FirebaseApp.initializeApp in order to initialize the default FirebaseApp instance using the configurations from the project's google-services.json file. (Those configurations are injected into the build as Android resources by the Google Services plugin.) However, If you're referencing multiple Firebase projects in one app, you'll have to write code to initialize other FirebaseApp instances, as discussed in an earlier blog post.
Some drawbacks with ContentProvider init
If you choose to use a ContentProvider to initialize your app or library, there's a couple things you need to keep in mind.
First, there can be only one ContentProvider on an Android device with a given "authority" string. So, if your library is used in more than one app on a device, you have to make sure that they get added with two different authority strings, or the second app will be rejected for installation. That string is defined for the ContentProvider in the manifest XML, which means it's effectively hard-coded. But there is a trick you can use with the Android build tools to make sure that each app build declares a different authority.
There is a feature of Android Gradle builds call manifest placeholders that lets you declare and insert a placeholder value that get inserted into manifest strings. The app's unique application ID is automatically available as a placeholder, so you can declare your ContentProvider like this:
<provider android:authorities="${applicationId}.yourcontentprovider" android:name=".YourContentProvider" android:exported="false" />
The other thing to know about about ContentProviders is that they are only run in the main process of an app. For a vast majority of apps, this isn't a problem, as there is only one process by default. But the moment you declare that one of the Android components in your app must run in another process, that process won't create any ContentProviders, which means your ContentProvider onCreate will never get invoked. In this case, the app will have to either avoid calling anything that requires the initialization, or safely initialize another way. Note that this behavior is different than a custom Application subclass, which does get invoked in every process for that app.
But why misuse ContentProvider like this?
Yes, it's true, this particular application of ContentProvider seems really weird, since it's not actually providing any content. And you have to provide implementations of all the other ContentProvider required methods by returning null. But, it turns out that this is the most reliable way to automatically initialize without requiring extra code. I think the convenience for developers using Firebase more than makes up for this strangeness of this use of a ContentProvider. Firebase is all about being easy to use, and there's nothing easier than no code at all!
Firebase provides a bunch of features to use together in your app, provided by a project that you create at the Firebase console. Normally, it's sufficient to have all your app's resources provided by a single project, but there are times when you want a single app to be able to access data from multiple projects. For example, you may need to access data from two different databases, and be able to authenticate users to access each one. I'll show you how that's done in this post.
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN) .requestIdToken(getString(R.string.default_web_client_id)) .requestEmail() .build();
google-services.json
FirebaseDatabase database = FirebaseDatabase.getInstance();
FirebaseOptions options = new FirebaseOptions.Builder() .setApplicationId("1:530266078999:android:481c4ecf3253701e") // Required for Analytics. .setApiKey("AIzaSyBRxOyIj5dJkKgAVPXRLYFkdZwh2Xxq51k") // Required for Auth. .setDatabaseUrl("https://project-1765055333176374514.firebaseio.com/") // Required for RTDB. .build(); FirebaseApp.initializeApp(this /* Context */, options, "secondary");
FirebaseApp
FirebaseDatabase.getInstance()
// Retrieve my other app. FirebaseApp app = FirebaseApp.getInstance("secondary"); // Get the database for the other app. FirebaseDatabase secondaryDatabase = FirebaseDatabase.getInstance(app);
.requestIdToken(getString(R.string.default_web_client_id))
{ "client_id": "56865680640-e8mr503bun5eaevqctn4u807q4hpi44s.apps.googleusercontent.com", "client_type": 3 },
AuthCredential credential = GoogleAuthProvider.getCredential(account.getIdToken(), null); FirebaseAuth.getInstance().signInWithCredential(credential); FirebaseApp app = FirebaseApp.getInstance("secondary"); FirebaseAuth.getInstance(app).signInWithCredential(credential);
Default Auth UID: 0960868722032022577213DA4EA8B7A1683D92B405DD Secondary Auth UID: 7h6XOeSxmkNsSseFJ1jU31WZHDP2
firebaseAuth.getCurrentUser().getToken(false /* forceRefresh */) .addOnCompleteListener(new OnCompleteListener() { @Override public void onComplete(@NonNull Task task) { String token = task.getResult().getToken(); // Send this to the server. } });
FirebaseOptions options = new FirebaseOptions.Builder() .setServiceAccount(new FileInputStream("default-service-account.json")) .build(); FirebaseApp.initializeApp(options); FirebaseOptions secondaryOptions = new FirebaseOptions.Builder() .setServiceAccount(new FileInputStream("secondary-service-account.json")) .build(); FirebaseApp.initializeApp(secondaryOptions, "secondary");
// Verify the ID token using the default app. FirebaseAuth.getInstance().verifyIdToken(idToken) .addOnSuccessListener(new OnSuccessListener() { @Override public void onSuccess(FirebaseToken decodedToken) { String uid = decodedToken.getUid(); System.out.println("User " + uid + " verified"); FirebaseApp app = FirebaseApp.getInstance("secondary"); String customToken = FirebaseAuth.getInstance(app).createCustomToken(uid); // TODO: Send the token back to the client! } });
FirebaseApp app = FirebaseApp.getInstance("secondary"); FirebaseAuth.getInstance(app).signInWithCustomToken(token);
Default Auth UID: 0960868722032022577213DA4EA8B7A1683D92B405DD Secondary Auth UID: 0960868722032022577213DA4EA8B7A1683D92B405DD
var config = { apiKey: "", authDomain: ".firebaseapp.com", databaseURL: "https://.firebaseio.com", storageBucket: ".appspot.com", messagingSenderId: "", }; var secondary = firebase.initializeApp(otherAppConfig, "secondary"); var secondaryDatabase = secondary.database();
// Alt: load from plist using |FIROptions(contentsOfFile:)| let options = FIROptions(googleAppID: googleAppID, bundleID: bundleID, GCMSenderID: GCMSenderID, APIKey: nil, clientID: nil, trackingID: nil, androidClientID: nil, databaseURL: databaseURL, storageBucket: nil, deepLinkURLScheme: nil) FIRApp.configure(withName: "secondary", options: fileopts) guard let secondary = FIRApp.init(named: "secondary") else { assert(false, "Could not retrieve secondary app") } let secondaryDatabase = FIRDatabase.database(app: secondary);
Over the course of this series, I've introduced the concept of Pirate Metrics, followed by individual posts discussing how to track (and improve) acquisition, activation and retention with Firebase and its' suite of products.
Every product owner dreams of seeing the work they create go viral. When your users love what you built so much that they want everyone around them to use it as well, it validates all the effort and hard work that went into it.
But here's the thing: while your users are typically more than happy to refer your application to their friends, family and colleagues, they are unlikely to be interested in putting in a lot of effort. The simple, easy way is to ensure you make it easy to simply share the URL for your application. However, you want to easily track how your referrals are doing, and you also want to smoothen the onboarding process for the new, incoming user.
The first product I'd like to talk about in this post is Dynamic Links. These links, which can be generated either on the Firebase console or programmatically, offer the benefit of redirecting users appropriately based on where they're opening them. That is, users on Android can be automatically sent to the Play Store while users on iOS can be sent to the App Store. If the user already has the app, they can be deeplinked to specific content inside it.
You can take Dynamic Links a few steps further as well by taking advantage of the fact that the data associated with each links survives the app installation process. This means that if the link was meant to deeplink to specific content (such as a product in an E-commerce service), you can take the user straight to the appropriate page once the new user completes the installation.
You can also consider using Dynamic Links to personalize the onboarding process for new users. For example, if you provide a referral bonus to users which relies on sharing of codes, you could ensure the link has this code already added as a parameter and add it automatically for the user right after install. This offers the opportunity to earn a lot of goodwill.
Links are only one part of the solution we have to offer - if you also use Firebase Invites, you can provide users with a simple options of choosing which contacts they would like to share your app with instead of relying upon third party apps. This list of contacts is also sorted to highlight those people the user frequently communicates with.
Firebase Invites referrals are sent over SMS and E-mails, and give you the benefits of Dynamic Links mentioned before. You can customize the invitation content, including the ability to specify templates with rich HTML content for E-mail. And you don't need the user to be signed in to your service or know their E-mail address either.
Your users are your best advocates, and we highly recommend minimizing the friction that might prevent them from sharing your application with the other people in their lives. Regardless of what your product is, you are likely to benefit from gently nudging - especially your more active ones.
Firebase Crash Reporting has enjoyed rapid adoption since its beta launch at Google I/O 2016. So far, we helped identify hundreds of millions of errors to help developers provide the best possible experience for users. Firebase Crash Reporting is now fully released, with many new features and enhancements to help you better diagnose and respond to crashes that affect the users of your iOS and Android mobile applications. Read on to discover what's new!
Issue Resolution
One of the most hotly requested features is the ability to mark an error cluster as "closed" in the dashboard, in order to indicate that the issue should be fixed, and that the next release should no longer generate that particular kind of crash. In the event of a regression in a future version, the crash cluster will be automatically reopened for context.
Improved Reporting Latency
The time it takes for a crash to be reported until the moment it appears in your console has been drastically decreased from about twenty minutes to less than a minute. We expect this improvement, in addition to email alerts, will improve your ability to diagnose errors as they happen.
Email Alerts
Anyone who has access to your Firebase project can arrange to receive an email alert if we see brand new clusters of errors, or errors that have regressed after being marked as closed. You can use this to quickly triage and respond to errors, in order to minimize the impact of a defect on your users.
Analytics events in Crash Logs
Firebase Analytics events are now added to your crash logs, which gives you a more complete view of the state of your app leading up to crash. This added context will also help you observe how crashes may be impacting your revenue and critical conversion events.
Mobile-Friendly Console
The Crash Reporting console has been improved for use on mobile devices. Its new responsive design makes it easy to check on the health of your apps when you're away from your desktop computer.
Android SDK Compatibility
The first release of the Android SDK had a limitation that prevented it from working well with some apps that declare an Application class. This limitation has been resolved, and Firebase Crash Reporting should work well with any Android app.
Updated Support for Swift on iOS
The service has been updated to show symbols from apps written in Swift 2 and 3.
We want your feedback!
If you decide to give Firebase Crash Reporting a try, please let us know how it went for you. For any questions about Crash Reporting or any other Firebase feature, please use the firebase-talk forum, or if it's a programming question, you can use the firebase tag on Stack Overflow.
Update: Both DebugView and StreamView are available to all Firebase developers, so you can get access to your data a whole lot faster! Happy Analytics viewing!
This is probably one of the most common questions we get around Firebase Analytics, and we thought it was worth taking some time to delve into this topic a little deeper. So buckle in, kids! We've got some learning ahead of us...
To understand latency with Firebase Analytics, there are two potential delays you need to be aware of:
Let's go over these one at a time.
Firebase Analytics doesn't constantly stream down data from the client device. That would be a serious battery drain, and we want to be respectful of your users' battery life. Instead, analytics data is batched up and sent down when the client library sees that there's any local data that's an hour old.
On iOS devices (and Android devices without Google Play Services), this one hour timer is per app. But on Android devices with Play Services, this one hour timer is across all apps using Firebase Analytics.
In addition, Firebase Analytics will send down all of its data from the client if your user triggers a conversion event (like making an in-app purchase). And on iOS devices, Firebase Analytics will also send down its data whenever your app goes into the background.
Not to worry. On most Android devices, it's Google Play Services that manages sending down this data. Which means that even if your user deletes your app after an hour, that data will still get sent down because Google Play Services still has it.
On iOS devices, Firebase will also send down data when your app moves into the background. So if a user tries your app for 20 minutes and then uninstalls it, that session data will still be received, because your app will have sent down the data the moment the user moved your app to the background. The one corner case where analytics data would actually get lost on iOS would be if your app crashed and then your user immediately uninstalled it.
Now, moving on to the second case, there's also the frequency at which Firebase Analytics grabs the latest batch of data it's received from your client and uses that data to update the reports and graphs you see in the Firebase Console. This process typically runs every few hours. So that's the kind of delay you should expect after your client data is sent down to the server.
If you're looking for your most recent data in these reports, keep in mind that the default "Last 30 days" report doesn't include any data from the current day -- this is because the data for the current day is incomplete, and it would be misleading (not to mention a bummer) to see every graph end with a giant downturn in usage. So if you want to see the current day's data, you'll want to select "Today" from the drop down menu in the Firebase Console.
On the other hand, if you've set up your app to export all of its Firebase analytics data to BigQuery, this data is available for you to look at right away. There are no batch reports that need to be run, so you can immediately view all of the day's data by looking at the app_events_intraday table that's automatically created for you in BigQuery. For more about this feature, be sure to check out our earlier blog post.
app_events_intraday
But outside of BigQuery, it generally takes a few hours for you to see any data you've recorded in Firebase Analytics.
As you may have heard at our Firebase Dev Summit, we've working on two enhancements to Firebase Analytics -- DebugView and StreamView -- which will give you more up-to-date insight into your analytics data during both development and production.
Neither of these are yet available to the general public, but as your reward for making it this far into the blog post, here's a link to sign up for the DebugView closed beta. See? Reading has its advantages!
There are many developers out there who want to be notified as soon as they see something unusual in their stats -- whether that's a sudden drop in in-app purchases, people failing to make it through the tutorial, or what-have-you.
And while you can't quite accomplish this with the free Firebase Analytics reports that you see in the console, you could accomplish this sort of thing by combining BigQuery with another tool such as Google Data Studio, a third-party visualization tool like Tableau, or even writing your own Google Apps Script monitoring script. All of which allow you to run some pretty sophisticated custom reports, but frankly, that's a whole other blog post.
Do keep in mind, however, that you're still subject to BigQuery usage charges when you query your data though these tools if you go beyond the 1TB/month free tier, so be mindful of how much (and how frequently) you decide to process your data.
Hopefully, this gives you a better understanding of how long it takes for you to see analytics data and what you can expect when you're developing your app. Now go forth and start recording those events!
