AWSMobilePushNotification

Serverless Mobile-Push-Notification server-side client and database abstraction/management for sending mobile push notifications to APNS and GCM utilizing Amazon DynamoDB and Amazon SimpleNotificationService implemented with .NET (Standards 1.6).

It maps your 'server-side defined User concept TO push notification sendable devices/platforms/endpoints and handles the management. Which gives you the ability to create a Mobile Push Notification service at your server-side only working and dealing with the Users of your application.

Designed initially for integrating Mobile Push Notification with scalable, serverless and stateless environments, like AWS Lambda

Key Features and Functionality

• Provides a UserId and Token level abstraction for your server-side application enabling you to only work with 'server-side defined User concept' and lifting the burden of token management/storage/validation.

• NoSQL DynamoDB provides limitless auto scaling and incredible speed for your application's need.

• Tagging enables sending batch notifications to multiple Users assigned to tags.

• Handles unavailable devices after a publish or optionally sets TimeToLive to clean-up later.

• Optionally writes logs of sent notifications to DynamoDB for querying later.

Overview

Check the WIKI page for API Reference and detailed explanations

Simplified visual summary

Coding Workflow

All the functions follows the same pattern, like AWSSDK.

Create Request -> Send Request -> Retrieve Response

1. Create a request to make. (Requires providing IAmazonDynamoDB and IAmazonSimpleNotificationService clients that the library will work on)
2. Modify the properties of the request
3. Send the request async
4. Evaluate the response

Glossary and Understanding the working logic

Library uses DynamoDB as the database and its incredibly fast. It creates and handles tables for certain functions, but the tables are available to you for adding extra functionalities or queries that are up to you.

Library provides an abstraction to your back-end's Users and internally stores / matches them as notification-sendable devices, letting you to work with only back-end specific identifiers which is called User in this library. A User can have multiple Subscribers, meaning mutliple devices that is available for sending a notification. For instance, a user logged in to multiple devices with the same account. In the absence of User, (Userless back-end logic) 'Device Identifier' of the mobile device can be used as an user identifier.

User is a collection of Subscribers. Its only represented by UserID

Subscriber is a tuple of UserId and NotificationToken. This represents a single notification-sendable endpoint for a User. Its the primary key and has to be unique. Without the UserId it should be the tuple of DeviceId and NotificationToken. Still unique.

So, to register a notification-sendable endpoint to your system you must specify both UserId and NotificationToken. In other words, a Subscriber can only be registered, not an User. However, when publishing a notification you can publish both to an User or to a Subscriber. User notifications will be sent to all of its registered endpoints(Subscribers), since its a collection of endpoints, which is mostly the desired functionality.

AppIdentfier property is used for DynamoDB table prefixes so that each of the back-end application is working with seperate tables with selected provisioned throughputs.

Getting Started

Installation

PM> Install-Package AWSMobilePushNotificationService

or

$ dotnet add package AWSMobilePushNotificationService

Requirements: .NET Standards 1.6 and Amazon SNS , Amazon DynamoDB

1. Obtain Platform Application ARN from AWS SNS using either your APNS Certificate or GCM API Keys
2. Create DynamoDB Tables at the first run (See example code below)
3. Its ready to operate...

Example Code

Check the WIKI page for detailed explanation

Implement the abstract class required for the any request to the library (for accessing AWS resources and configuration)

public abstract class DefaultAWSMobilePushNotificationConfigProvider : IAWSMobilePushNotificationConfigProvider
{

    public abstract IAmazonDynamoDB DynamoDBClient { get; } //DynamoDB client

    public abstract IAmazonSimpleNotificationService SNSClient { get; } //SNS client

    public abstract string AppIdentifier { get; } //DynamoDB table and SNS topic prefixes

    public abstract TimeSpan? SubscriberTimeToLive { get; } // TTL for a subscriber

    public abstract TimeSpan? IterativeTagTimeToLive { get; } // TTL for a tag

    // Default context. Make sure you set prefixes if you directly implement the interface but not the abstract class
    public DynamoDBContextConfig DynamoDBCcontextConfig
    {
        get
        {
            return new DynamoDBContextConfig
            {
                TableNamePrefix = AppIdentifier,
                ConsistentRead = false,
                SkipVersionCheck = true
            };
        }
    }
    
    public abstract bool CatchAllExceptions { get; } // Catch every exception and put it in the response

}

Create required DynamoDB tables at the first run (you can adjust provisioned throughput at anytime)

CreateApplicationTablesRequest request = new CreateApplicationTablesRequest(MY_IMPLEMENTATION_OF_INTERFACE);
request.SubscribersTable = new CreateApplicationTablesRequest.TableProperty { ReadCapacity = 1, WriteCapacity = 1, TTLEnabled = false };

//Rest is optional if you want to enable Tagging
request.TagsTable = new CreateApplicationTablesRequest.TableProperty { ReadCapacity = 1, WriteCapacity = 1, TTLEnabled = false };
request.IterativeTagsTable = new CreateApplicationTablesRequest.TableProperty { ReadCapacity = 1, WriteCapacity = 1, TTLEnabled = false };
request.SNSTopicTagsTable = new CreateApplicationTablesRequest.TableProperty { ReadCapacity = 1, WriteCapacity = 1 };

//Optional Log table to write sending logs
request.LogTable = new CreateApplicationTablesRequest.TableProperty { ReadCapacity = 1, WriteCapacity = 1 };

var result = await request.SendAsync();
            

Register the User first, after retrieving its token from the device

RegisterSubscriberRequest request = new RegisterSubscriberRequest(MY_IMPLEMENTATION_OF_INTERFACE);
request.DeviceId = "DeviceId_from_mobile_device"; //Stored in DynamoDB 
request.UserId = "Identifier_of_this_user_for_my_back-end"; // Use DeviceId if UserID isnt available
request.NotificationToken = "Token_from_mobile_devices";
request.Platform = 1; // 1 for APNS, 2 for GCM

// Put your own ApplicationPlatformARNs
if (request.Platform == Platform.APNS)
{
    request.ApplicationPlatformArn = appSettings.APNSApplicationPlatformARN;
}
else
{
    request.ApplicationPlatformArn = appSettings.GCMApplicationPlatformARN;
}

// For example assign this subscriber to a tag directly at registration
// Check wiki for tagging details and types
var tags = new List<PNAttributedTag>();
tags.Add(new PNAttributedTag{Tag = "AllSubscribers", TagMethod = PNTagType.SNSTopic});
request.Tags = tags;

RegisterResult result = await request.SendAsync();

Send a notification to a User (meaning to all of its Subscribers, devices - endpoints )

PublishToUserRequest request = new PublishToUserRequest(MY_IMPLEMENTATION_OF_INTERFACE);

APNSNotificationPayload apnsPayload = new APNSNotificationPayload();
apnsPayload.Body = "MessageBody";
apnsPayload.Title = "Title";
apnsPayload.Content_Available = 1;
apnsPayload.Add("CustomKey", "CustomValue");


GCMNotificationPayload gcmPayload = new GCMNotificationPayload(apnsPayload);
gcmPayload.Body = "MessageBody";
gcmPayload.Title = "Title";
gcmPayload.Add("CustomKey1", "CustomValue1");

request.SetPayload(apnsPayload, gcmPayload);

// Or instead of seperate payloads use mutual payload
/*
NotificationPayload mutualPayload = new NotificationPayload();
mutualPayload.Add("CustomKey2", "CustomValue2");
mutualPayload.Body = "MessageBody";
mutualPayload.Title = "Title";
request.SetPayload(mutualPayload);
    */

request.UserId = "Identifier_of_this_user_for_my_back-end";
request.SnsDefaultMessage = "DefaultSNSMessage";
request.TimeToLive = "TTL_in_Seconds";

// Its published to a User. So, there can be list of results return from publishing multiple subscribers
List<PublishToSNSResult> results = await request.SendAsync();

Check the WIKI page for API Reference and detailed explanations

License

MIT