Getting Started

This example describes how PushServer is configured in an ASP.NET Web Application using EntityFrameworkCore to persist push subscriptions.

Installation

The following packages need to be added to the project:

Install-Package PushServer
Install-Package PushServer.PushConfiguration.EntityFramework
Install-Package PushServer.WebPush

Configuration

ConfigurationStore

In Startup.cs configure the PushServer framework.

services.AddPushServer();

In this example, EntityFrameworkCore is used to persist subscriptions. The store is configured using the DbContextOptionsBuilder, e.g.

services.AddPushServer()
  .AddConfigurationStore(builder =>
    builder.UseSqlServer(connectionString)))

I tend to use SqlLite

var connectionString = $"Data Source={HostingEnvironment.WebRootPath}\\App_Data\\pushservice.db";
var migrationsAssembly = typeof(Startup).GetTypeInfo().Assembly.GetName().Name;
services.AddPushServer()
  .AddConfigurationStore(builder =>
    builder.UseSqlite(connectionString, sql => sql.MigrationsAssembly(migrationsAssembly)))

Push provider(s)

Now the push providers required for this project are configured. This example describes the configuration of a web push (Web Push Protocol) provider.

services.AddPushServer()
  .AddConfigurationStore(...)
  .AddWebPush(v =>
    {
      v.PrivateKey = "VapidPrivateKey";
      v.PublicKey = "VapidPublicKey";
      v.Subject = "mailto:yoursubject.com";
    });

For details on VAPID and the Web Push Protocol I recommend this introduction. The keys can be generated using the nodejs webpush cli

npm install web-push -g
web-push generate-vapid-keys --json

Storing a subscription

When you send the push subscription details from your client application to your web app, they can be stored by using IPushConfigurationManager. To identify the subscriptions owner, a string userId must be provided.

[Route("api/[controller]")]
  public class PushSubscriptionController : ControllerBase
  {
     private readonly IPushConfigurationManager pushConfigurationManager;
     public PushSubscriptionController (IPushConfigurationManager pushConfigurationManager)
     {
       this.pushConfigurationManager = pushConfigurationManager;
     }
     [HttpPost()]
     [Authorize]
     public async Task<IActionResult> Register([FromBody]WebPushChannelRegistration registration)
     {
       ...
       await pushConfigurationManager.RegisterAsync(userId, registration);
       ...
     }

To be able to identify a subscription later on, the pushChannelOptions, key value pairs can be supplied, e.g.

registration.Options = new Dictionary<string,string>() { { "device", "usersmartphone" } };

Finding subscriptions

All stored subscriptions of a user can be accessed using IPushConfigurationManager.GetAllAsync

await pushConfigurationManager.GetAllAsync(userId)

Requesting notification delivery

Now that a subscription is stored, you can request notification delivery using IPushService.Push. There are two possibilites to identify push subscriptions a notification should be sent to:

1. subscription id, which is generated by the pushConfigurationManager on RegisterAsync
2. userId and key value pairs of attributes accessed with subscriptions.

await pushService.Push("configurationId", "push notification payload", null);

await pushService.Push("userId",
  new Dictionary<string,string>() { { "device", "usersmartphone" } },
 "push notification payload", null);