Slinger - deep linking library for Android

Slinger is a small Android library for handling custom Uri which uses regular expression to catch and route URLs which won’t be handled by normal intent-filter mechanism.

With slinger it’s possible to provide deep links for quite complicated URLs.

How do I use it?

Declare Activity in your manifest with your own IntentResolver that will handle links within particular domain.

<activity
  android:name="pl.allegro.android.slinger.SlingerActivity"
  android:excludeFromRecents="true"
  android:noHistory="true"
  android:theme="@style/android:Theme.NoDisplay">
  <meta-data
    android:name="IntentResolver"
    android:value="com.my.appp.ExampleIntentResolver"/>
    <intent-filter android:label="@string/app_name">
      <action android:name="android.intent.action.VIEW"/>
      <category android:name="android.intent.category.DEFAULT"/>
      <category android:name="android.intent.category.BROWSABLE"/>
      <data
        android:host="example.com"
        android:pathPattern="/.*"
        android:scheme="http"/>
    </intent-filter>
</activity>

IntentResolver is a class that redirects URLs to concrete Activities based on regular expressions.

@Keep
public class ExampleIntentResolver extends IntentResolver {

  private List<RedirectRule> rules;

  public ExampleIntentResolver(Activity activity) {
    super(activity);
    rules = asList(getRedirectRuleForAboutActivity(activity));
  }

  private RedirectRule getRedirectRuleForAboutActivity(Activity activity) {
    return RedirectRule.builder()
                       .intent(new Intent(activity, MyConcreteActivityA.class))
                       .pattern("http://example.com/abc\\\\.html\\\\?query=a.*")
                       .build();
  }

  @NonNull @Override public Iterable<RedirectRule> getRules() {
    return rules;
  }
}

In case when no redirect rule is matched IntentResolver will fallback to default Intent - Uri with ACTION_VIEW.

Customizing

Matching Activities

In order to provide other mechanism than regular expression matching you can override resolveIntentToSling in IntentResolver

Enriching Slinged Intents with Referrer and input URL

Slinger enriches Intents with URL and referrer by default. This can be changed by overriding enrichIntent in IntentResolver

@Keep
public class ExampleIntentResolver extends IntentResolver {

  @NonNull
  @Override
  public Intent resolveIntentToSling(@NonNull Uri originatingUri) {
    // implement own intent resolving strategy here
    return super.resolveIntentToSling(originatingUri);
  }
  
  @Override
  public Intent enrichIntent(Activity parentActivity, Intent resolvedIntent, Uri originatingUri) {
    // enrich resolved intent with custom data
    return super.enrichIntent(parentActivity, resolvedIntent, originatingUri).putExtra("foo","bar");
  }
}

Security considerations

Slinger does not sanitize input in any way. So providing security for application is your responsibility.

License

slinger is published under Apache License 2.0.

allegro / slinger