DeepLinkDispatch

DeepLinkDispatch provides a declarative, annotation-based API to define application deep links.

You can register an Activity to handle specific deep links by annotating it with @DeepLink and a URI. DeepLinkDispatch will parse the URI and dispatch the deep link to the appropriate Activity, along with any parameters specified in the URI.

Example

Here's an example where we register SampleActivity to pull out an ID from a deep link like example://example.com/deepLink/123. We annotated with @DeepLink and specify there will be a parameter that we'll identify with id.

@DeepLink("foo://example.com/deepLink/{id}")
public class MainActivity extends Activity {
  @Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Intent intent = getIntent();
    if (intent.getBooleanExtra(DeepLink.IS_DEEP_LINK, false)) {
      Bundle parameters = intent.getExtras();
      String idString = parameters.getString("id");
      // Do something with idString
    }
  }
}

Multiple Deep Links

Sometimes you'll have an Activity that handles several kinds of deep links:

@DeepLink({"foo://example.com/deepLink/{id}", "foo://example.com/anotherDeepLink"})
public class MainActivity extends Activity {
  @Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Intent intent = getIntent();
    if (intent.getBooleanExtra(DeepLink.IS_DEEP_LINK, false)) {
      Bundle parameters = intent.getExtras();
      String idString = parameters.getString("id");
      // Do something with idString
    }
  }
}

Method Annotations

You can also annotate any public static method with @DeepLink. DeepLinkDispatch will call that method to create the Intent and will use it when starting your Activity via that registered deep link:

@DeepLink("foo://example.com/methodDeepLink/{param1}")
public static Intent intentForDeepLinkMethod(Context context) {
  return new Intent(context, MainActivity.class)
      .setAction(ACTION_DEEP_LINK_METHOD);
}

If you need access to the Intent extras, just add a Bundle parameter to your method, for example:

@DeepLink("foo://example.com/methodDeepLink/{param1}")
public static Intent intentForDeepLinkMethod(Context context, Bundle extras) {
  Uri.Builder uri = Uri.parse(extras.getString(DeepLink.URI)).buildUpon();
  return new Intent(context, MainActivity.class)
      .setData(uri.appendQueryParameter("bar", "baz").build())
      .setAction(ACTION_DEEP_LINK_METHOD);
}

If you're using Kotlin, make sure you also annotate your method with @JvmStatic. companion objects will not work, so you can use an object declaration instead:

object DeeplinkIntents {
  @JvmStatic 
  @DeepLink("https://example.com")
  fun defaultIntent(context: Context, extras: Bundle): Intent {
    return Intent(context, MyActivity::class.java)
  }
}

If you need to customize your Activity backstack, you can return a TaskStackBuilder instead of an Intent. DeepLinkDispatch will call that method to create the Intent from the TaskStackBuilder last Intent and use it when starting your Activity via that registered deep link:

@DeepLink("http://example.com/deepLink/{id}/{name}")
public static TaskStackBuilder intentForTaskStackBuilderMethods(Context context) {
  Intent detailsIntent =  new Intent(context, SecondActivity.class).setAction(ACTION_DEEP_LINK_COMPLEX);
  Intent parentIntent =  new Intent(context, MainActivity.class).setAction(ACTION_DEEP_LINK_COMPLEX);
  TaskStackBuilder  taskStackBuilder = TaskStackBuilder.create(context);
  taskStackBuilder.addNextIntent(parentIntent);
  taskStackBuilder.addNextIntent(detailsIntent);
  return taskStackBuilder;
}

Query Parameters

Query parameters are parsed and passed along automatically, and are retrievable like any other parameter. For example, we could retrieve the query parameter passed along in the URI foo://example.com/deepLink?qp=123:

@DeepLink("foo://example.com/deepLink")
public class MainActivity extends Activity {
  @Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Intent intent = getIntent();
    if (intent.getBooleanExtra(DeepLink.IS_DEEP_LINK, false)) {
      Bundle parameters = intent.getExtras();
      if (parameters != null && parameters.getString("qp") != null) {
        String queryParameter = parameters.getString("qp");
        // Do something with the query parameter...
      }
    }
  }
}

Callbacks

You can optionally register a BroadcastReceiver to be called on any incoming deep link into your app. DeepLinkDispatch will use LocalBroadcastManager to broadcast an Intent with any success or failure when deep linking. The intent will be populated with these extras:

DeepLinkHandler.EXTRA_URI: The URI of the deep link.
DeepLinkHandler.EXTRA_SUCCESSFUL: Whether the deep link was fired successfully.
DeepLinkHandler.EXTRA_ERROR_MESSAGE: If there was an error, the appropriate error message.

You can register a receiver to receive this intent. An example of such a use is below:

public class DeepLinkReceiver extends BroadcastReceiver {
  private static final String TAG = "DeepLinkReceiver";

  @Override public void onReceive(Context context, Intent intent) {
    String deepLinkUri = intent.getStringExtra(DeepLinkHandler.EXTRA_URI);
    if (intent.getBooleanExtra(DeepLinkHandler.EXTRA_SUCCESSFUL, false)) {
      Log.i(TAG, "Success deep linking: " + deepLinkUri);
    } else {
      String errorMessage = intent.getStringExtra(DeepLinkHandler.EXTRA_ERROR_MESSAGE);
      Log.e(TAG, "Error deep linking: " + deepLinkUri + " with error message +" + errorMessage);
    }
  }
}

public class YourApplication extends Application {
  @Override public void onCreate() {
    super.onCreate();
    IntentFilter intentFilter = new IntentFilter(DeepLinkHandler.ACTION);
    LocalBroadcastManager.getInstance(this).registerReceiver(new DeepLinkReceiver(), intentFilter);
  }
}

Custom Annotations

You can reduce the repetition in your deep links by creating custom annotations that provide common prefixes that are automatically applied to every class or method annotated with your custom annotation. A popular use case for this is with web versus app deep links:

// Prefix all app deep link URIs with "app://airbnb"
@DeepLinkSpec(prefix = { "app://airbnb" })
public @interface AppDeepLink {
  String[] value();
}

// Prefix all web deep links with "http://airbnb.com" and "https://airbnb.com"
@DeepLinkSpec(prefix = { "http://airbnb.com", "https://airbnb.com" })
public @interface WebDeepLink {
  String[] value();
}

// This activity is gonna hanndle the following deep links:
// "app://airbnb/view_users"
// "http://airbnb.com/users"
// "http://airbnb.com/user/{id}"
// "https://airbnb.com/users"
// "https://airbnb.com/user/{id}"
@AppDeepLink({ "/view_users" })
@WebDeepLink({ "/users", "/user/{id}" })
public class CustomPrefixesActivity extends AppCompatActivity {
    //...
}

Usage

Add to your project build.gradle file:

dependencies {
  compile 'com.airbnb:deeplinkdispatch:3.1.1'
  annotationProcessor 'com.airbnb:deeplinkdispatch-processor:3.1.1'
}

Create your deep link module(s) (new on DeepLinkDispatch v3). For every class you annotate with @DeepLinkModule, DeepLinkDispatch will generate a "Loader" class, which contains a registry of all your @DeepLink annotations.

/** This will generate a AppDeepLinkModuleLoader class */
@DeepLinkModule
public class AppDeepLinkModule {
}

Optional: If your Android application contains multiple modules (eg. separated Android library projects), you'll want to add one @DeepLinkModule class for every module in your application, so that DeepLinkDispatch can collect all your annotations in one "loader" class per module:

/** This will generate a LibraryDeepLinkModuleLoader class */
@DeepLinkModule
public class LibraryDeepLinkModule {
}

Create any Activity (eg. DeepLinkActivity) with the scheme you'd like to handle in your AndroidManifest.xml file (using foo as an example):

<activity
    android:name="com.example.DeepLinkActivity"
    android:theme="@android:style/Theme.NoDisplay">
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />
        <data android:scheme="foo" />
    </intent-filter>
</activity>

Annotate your DeepLinkActivity with @DeepLinkHandler and provide it a list of @DeepLinkModule annotated class(es):

@DeepLinkHandler({ AppDeepLinkModule.class, LibraryDeepLinkModule.class })
public class DeepLinkActivity extends Activity {
  @Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // DeepLinkDelegate, LibraryDeepLinkModuleLoader and AppDeepLinkModuleLoader
    // are generated at compile-time.
    DeepLinkDelegate deepLinkDelegate = 
        new DeepLinkDelegate(new AppDeepLinkModuleLoader(), new LibraryDeepLinkModuleLoader());
    // Delegate the deep link handling to DeepLinkDispatch. 
    // It will start the correct Activity based on the incoming Intent URI
    deepLinkDelegate.dispatchFrom(this);
    // Finish this Activity since the correct one has been just started
    finish();
  }
}

Notes

Starting with DeepLinkDispatch v3, you have to always provide your own Activity class and annotate it with @DeepLinkHandler. It's no longer automatically generated by the annotation processor.
Intent filters may only contain a single data element for a URI pattern. Create separate intent filters to capture additional URI patterns.
Please refer to the sample app for an example of how to use the library.

Snapshots of the development version are available in Sonatype's snapshots repository.

Generated deep links Documentation

You can tell DeepLinkDispatch to generate text a document with all your deep link annotations, which you can use for further processing and/or reference. In order to do that, add to your build.gradle file:

tasks.withType(JavaCompile) {
  options.compilerArgs << "-AdeepLinkDoc.output=${buildDir}/doc/deeplinks.txt"
}

The documentation will be generated in the following format:

* {DeepLink1}\n|#|\n[Description part of javadoc]\n|#|\n{ClassName}#[MethodName]\n|##|\n
* {DeepLink2}\n|#|\n[Description part of javadoc]\n|#|\n{ClassName}#[MethodName]\n|##|\n

Proguard Rules

-keep class com.airbnb.deeplinkdispatch.** { *; }
-keepclasseswithmembers class * {
     @com.airbnb.deeplinkdispatch.DeepLink <methods>;
}

Note: remember to include Proguard rules to keep Custom annotations you have used, for example by package:

-keep @interface your.package.path.deeplink.** { *; }
-keepclasseswithmembers class * {
    @your.package.path.deeplink.* <methods>;
}

Testing the sample app

Use adb to launch deep links (in the terminal type: adb shell).

This fires a standard deep link. Source annotation @DeepLink("dld://example.com/deepLink")

am start -W -a android.intent.action.VIEW -d "dld://example.com/deepLink" com.airbnb.deeplinkdispatch.sample

This fires a deep link associated with a method, and also passes along a path parameter. Source annotation @DeepLink("dld://methodDeepLink/{param1}")

am start -W -a android.intent.action.VIEW -d "dld://methodDeepLink/abc123" com.airbnb.deeplinkdispatch.sample

You can include multiple path parameters (also you don't have to include the sample app's package name). Source annotation @DeepLink("http://example.com/deepLink/{id}/{name}")

am start -W -a android.intent.action.VIEW -d "http://example.com/deepLink/123abc/myname"

Note it is possible to call directly adb shell am ... however this seems to miss the URI sometimes so better to call from within shell.

License

Copyright 2015 Airbnb, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

ArslanKathia/DeepLinkDispatch