Android-DDP

This library implements the Distributed Data Protocol (DDP) from Meteor for clients on Android.

Connect your native Android apps, written in Java, to apps built with the Meteor framework and build real-time features.

Motivation

• Have you built a web application with Meteor?
  • Using this library, you can build native Android apps that can talk to your Meteor server and web application.
• Are you primarily an Android developer (who has never heard of Meteor)?
  • With "Android-DDP", you can use a Meteor server as your backend for real-time applications on Android.
• Doesn't Meteor provide built-in features for Android app development already?
  • With Meteor's built-in features, your Android app will be written in HTML, CSS and JavaScript, wrapped in a WebView. It will not be a native app.
  • By using this library, however, you can write native Android apps in Java while still using Meteor as your real-time backend.

Installation

• Add this library to your project

  • Include one of the JARs in your libs folder
  • or
  • Copy the Java package to your project's source folder
  • or
  • Create a new library project from this repository and reference it in your project

• Add the Internet permission to your app's AndroidManifest.xml:

  <uses-permission android:name="android.permission.INTERNET" />

Usage

• Creating a new instance of the DDP client

  public class MyActivity extends Activity implements MeteorCallback {
  
      private Meteor mMeteor;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
  
   	   // ...
  
   	   mMeteor = new Meteor(this, "ws://example.meteor.com/websocket");
   	   mMeteor.setCallback(this);
      }
  
      public void onConnect(boolean signedInAutomatically) { }
  
      public void onDisconnect(int code, String reason) { }
  
      public void onDataAdded(String collectionName, String documentID, String newValuesJson) { }
  
      public void onDataChanged(String collectionName, String documentID, String updatedValuesJson, String removedValuesJson) { }
  
      public void onDataRemoved(String collectionName, String documentID) { }
  
      public void onException(Exception e) { }
  
  }
  

• Singleton access

  • Creating an instance at the beginning

    MeteorSingleton.createInstance(this, "ws://example.meteor.com/websocket")
    // instead of
    // new Meteor(this, "ws://example.meteor.com/websocket")
    

  • Accessing the instance afterwards (across Activity instances)

    MeteorSingleton.getInstance()
    // instead of
    // mMeteor
    

  • Registering a callback

    MeteorSingleton.getInstance().setCallback(this);
    // instead of
    // mMeteor.setCallback(this);
    

  • Unregistering a callback

    MeteorSingleton.getInstance().unsetCallback(this);

  • All other API methods can be called on MeteorSingleton.getInstance() just as you would do on any other Meteor instance, as documented here with mMeteor

• Inserting data into a collection

  Map<String, Object> values = new HashMap<String, Object>();
  values.put("_id", "my-id");
  values.put("some-key", "some-value");
  
  mMeteor.insert("my-collection", values);
  // or
  // mMeteor.insert("my-collection", values, new ResultListener() { });
  

• Updating data in a collection

  Map<String, Object> query = new HashMap<String, Object>();
  query.put("_id", "my-id");
  
  Map<String, Object> values = new HashMap<String, Object>();
  values.put("some-key", "some-value");
  
  mMeteor.update("my-collection", query, values);
  // or
  // mMeteor.update("my-collection", query, values, options);
  // or
  // mMeteor.update("my-collection", query, values, options, new ResultListener() { });
  

• Deleting data from a collection

  mMeteor.remove("my-collection", "my-id");
  // or
  // mMeteor.remove("my-collection", "my-id", new ResultListener() { });
  

• Subscribing to data from the server

  String subscriptionId = mMeteor.subscribe("my-subscription");
  // or
  // String subscriptionId = mMeteor.subscribe("my-subscription", new Object[] { arg1, arg2 });
  // or
  // String subscriptionId = mMeteor.subscribe("my-subscription", new Object[] { arg1, arg2 }, new SubscribeListener() { });
  

• Unsubscribing from a previously established subscription

  mMeteor.unsubscribe(subscriptionId);
  // or
  // mMeteor.unsubscribe(subscriptionId, new UnsubscribeListener() { });
  

• Calling a custom method defined on the server

  mMeteor.call("myMethod");
  // or
  // mMeteor.call("myMethod", new Object[] { arg1, arg2 });
  // or
  // mMeteor.call("myMethod", new ResultListener() { });
  // or
  // mMeteor.call("myMethod", new Object[] { arg1, arg2 }, new ResultListener() { });
  

• Disconnect from the server

  mMeteor.disconnect()

• Creating a new account (requires accounts-password package)

  mMeteor.registerAndLogin("john", "john.doe@example.com", "password", new ResultListener() { });
  // or
  // mMeteor.registerAndLogin("john", "john.doe@example.com", "password", profile, new ResultListener() { });
  

• Signing in with an existing username (requires accounts-password package)

  mMeteor.loginWithUsername("john", "password", new ResultListener() { });

• Signing in with an existing email address (requires accounts-password package)

  mMeteor.loginWithEmail("john.doe@example.com", "password", new ResultListener() { });

• Check if the client is currently logged in (requires accounts-password package)

  mMeteor.isLoggedIn()

• Get the client's user ID (if currently logged in) (requires accounts-password package)

  mMeteor.getUserId()

• Logging out (requires accounts-password package)

  mMeteor.logout();
  // or
  // mMeteor.logout(new ResultListener() { });
  

• Checking whether the client is connected

  mMeteor.isConnected()

• Manually attempt to re-connect (if necessary)

  mMeteor.reconnect()

Contributing

All contributions are welcome! If you wish to contribute, please create an issue first so that your feature, problem or question can be discussed.

Dependencies

• Autobahn|Android — Tavendo — Apache License 2.0
• Jackson Core — FasterXML — Apache License 2.0
• Jackson ObjectMapper — FasterXML — Apache License 2.0

Further reading

• DDP — Specification
• Jackson — Documentation
• Autobahn|Android — API documentation

Disclaimer

This project is neither affiliated with nor endorsed by Meteor or Firebase.

License

Copyright 2014 www.delight.im <info@delight.im>

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.