advanced-http4s

Code samples of advanced features of Http4s in combination with some features of Fs2 not often seen.

Streaming end to end

• Server: Streaming responses end to end, from the FileService reading all the directories in your $HOME directory to the FileHttpEndpoint.
• StreamClient: Parsing chunks of the response body produced by the server in a streaming fashion way.

You'll need two sbt sessions. Run the server in one and after the client in the other to try it out.

Middleware Composition

• GZip: For compressed responses. Client must set the Accept Encoding header to gzip.
• AutoSlash: To make endpoints work with and without the slash / at the end.

Response compression is verified by HexNameHttpEndpointSpec. You can also try it out on Postman or similar.

• Timeout: Handling response timeouts with the given middleware.

The TimeoutHttpEndpoint generates a response in a random time to demonstrate the use.

• NonStreamResponse: Using the ChunkAggregator middleware to wrap the streaming FileHttpEndpoint and remove the Chunked Transfer Encoding.

The endpoint /v1/nonstream/dirs?depth=3 demonstrates the use case.

Media Type negotiation

• XML and Json: Decoding request body with either of these types for the same endpoint.

The JsonXmlHttpEndpoint demonstrates this use case and it's validated in its spec.

Multipart Form Data

• Server: The MultipartHttpEndpoint is responsible for parsing multipart data with the given multipart decoder.
• MultipartClient: Example uploading both text and an image.

Similar to the streaming example, you'll need to run both Server and MultipartClient to see how it works.

NOTE: Beware of the creation of rick.jpg file in your HOME directory!

Authentication

• Basic Auth: Using the given middleware as demonstrated by the BasicAuthHttpEndpoint.
• OAuth 2: Using GitHub as demonstrated by the GitHubHttpEndpoint.

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fs2 examples

In the fs2 package you'll find some practical examples of the few things it's possible to build with this powerful streaming library. This might serve as a starting point, your creativity will do the rest.

fs2.async package

Apart from the use of the three core types Stream[F, O], Pipe[F, I, O] and Sink[F, I] you'll find examples of use of the following types:

• Topic[F, A]
• Signal[F, A]
• Queue[F, A]
• Ref[F, A]
• Promise[F, A]
• Semaphore[F]

In addition to the use of some other functions useful in Parallel and Concurrent scenarios.