pubnub.async

An async/await, testable, extensible, fluent api, easy-to-use, cross-platform PubNub client.

Branch	Nuget	Build	Test Coverage	Static Analysis
master
development

Disclaimer

❗ This is an unofficial .net client for the cloud messaging service PubNub. If you like to keep things official, I'd suggest heading over to their repository.

Intoducing...

Still with me? I'm on a mission to improve upon the stock offering of the PubNub service client. Here are my goals:

1. Async/Await: The stock PubNub client forces you into callback hell, with separate success/error/etc callbacks based on the response scenario. I think the client should be responsible for abstracting this for the developer by returning a consistent response model that describes success, failure, or otherwise.
2. Dependency Injection: PubNub's client is implemented largely in one code file containing several classes and utility functions. pubnub.async employs development best practices like separation of concerns. I've provided a nuget package to get you up and running with Autofac as my container of choice. If you'd like to see other containers supported, please open an issue or submit a pull request.
3. Testability: the stock client's high amount of coupling without the use of interfaces makes it very difficult to mock during testing. Hand in hand with goal #2 above, we all know IoC helps out a lot with testability. I am also working on a test framework to make testing with the client even easier in your own application tests.
4. Fluent API: It seems, these days, you've gotta have a fluent API! More details on this later.
5. Extensibility: Through a nifty application of extension methods, it's easy to bolt on additional features with additional nuget packages. My first planned candidate for this is mobile push notifications as I see this feature living outside the client's "core" feature set.
6. Easy to Use: This client will do as much of the work for you as possible.

• It'll batch history requests into groups of 200 messages (PubNub's max) for you and aggregate the results.
• If a channel is secured with PubNub Access Manager, pubnub.async will request and manage all grants for you if you've provided your secret key.
• Application-level delegates for lifecyle events like message recieved on any channel, success, or error.

Fluenticity

Yes, that's a made up word. Below are some examples of what it means.

// Everything revolves around a channel
var history = await "channelA".History<ApplicationSpecificMessageModel>();
var ancientHistory = await new Channel("channelB").History<ApplicationSpecificMessageModel>();

// you can specifically configure a single shot channel...
var response = await "particular-config-channel"
	.SecuredWith(AuthKey) //enables & handles PAM
	.EncryptedWith(CipherKey) //enables & handles encryption
	.Publish(HelloWorld); // publish a message

// or configure a reusable client
var client = "multi-use"
	.SecuredWith(AuthKey)
	.EncryptedWith(CipherKey);
var response = await client.Publish(YourMessageModel);
var history = await client.History<YourMessageModel>();

// you may, additionally, configure an application-level configuration, ideally at application startup...
PubNub.Configure(c =>
{
	c.SessionUuid = "system";
	c.PublishKey = Settings.Default.PublishKey;
	c.SubscribeKey = Settings.Default.SubscribeKey;
	c.SecretKey = Settings.Default.SecretKey;
	c.CipherKey = "42";
});

// yet still override the global config as needed
var specialClient = "special-channel"
	.ConfigurePubNub(c =>
	{
		c.SessionUuid = "userId";
		c.CipherKey = "special";
		c.MinutesToTimeout = 20;
	});

Testability

I'm a fan of Moq, and I hope you are too. This is still a work in progress, but the groundwork for a basic testing framework is in place. The end result should look something like this:

using(var pubNubTest = new PubNubTest())
{
  pubNubTest.MockAccess
    .Setup(x => x.Establish(AccessType.ReadWrite))
    .Returns(expectedGrantResponse);
  
  var result = await "test-channel"
    .Secured()
    .Grant(AccessType.ReadWrite);
  
  Assert.Equal(expectedGrantResponse, result);
}