Provide a way to send a JSON object with `WebClient`

[ikhoon]

JSON is the dominant exchange format for REST API. However, Armeria's WebClient does not provide any JSON-specific APIs. I believe it should be useful additions if we provide:

WebClient client = WebClient.of();
// Send a serialized JSON object with "applicaiton/json"
HttpResponse response = client.postJson("/items", new MyItem()); 
HttpResponse response = client.putJson("/items", new MyItem());
HttpResponse response = client.patchJson("/items", new MyItem());

HttpResponse response = client.prepare()
                              .post("/items")
                              .contentJson(new MyItem())
                              .execute();

[0x1306e6d]

Additionally, how do you think similar feature, HttpRequest.ofJson? Additionally, how about adding HttpRequest.ofJson also?

[trustin]

+1 to having HttpRequest.ofJson() as well.

[ikhoon]

It would also be nice to have APIs that automatically convert a response into an object.

• Content-Type
  • We can support well-known media types such as:
  • "application/json"
  • "application/protobuf" (We can add this later cause Protobuf is not a popular format for REST.)
  • An UnsupportedMediaTypeException could complete the returned future for unknown media types.
  • An JsonProcessingException could complete the returned future when failing to decode a JSON in response body into an object.
• Status
  • The default expected HTTP response is 200 OK. If another status is received;
  • UnexpectedHttpStatusException could complete the returned future.
  • Alternatively, an additional API that can specify an expected HTTP status.

interface HttpResponse {
  <T> CompletableFuture<T> aggregateAs(Class<? extends T> clazz);
  <T> CompletableFuture<T> aggregateAs(HttpStatus expectedStatus, Class<? extends T> clazz);
  <T> CompletableFuture<T> aggregateAs(HttpStatus expectedStatus, Class<? extends T> clazz, EventExecutor executor);
}

[karellen-kim]

I'm interested in this!

[ikhoon]

Thanks! It's all yours.