Play Framework examine HTTP request

Question

I was wondering how to examine an HTTP request in Play Framework 2.1. The only information I can find on the documentation is via the conf/routes mechanism:

GET   /clients/:id          controllers.Clients.show(id: Long)  

but this will only allow us to get the parameter id from the path. How do I access other part of the request, such as header or query params? In other words, what are Play's equivalents of JAX-RS @HeaderParam, @FormParam, @QueryParam and such?

Solution 1

Within an action, you can get the request header using the request() method, for instance, in Java:

public static Result index() {
  // example of a Header
  String userAgent = request().getHeader("User-Agent");

  // example of a query parameter
  String q = request().getQueryString("q");
  ...
}

You can take a look at the API for Java or Scala.

Solution 2

Better use a constant than a hardcoded String, in Scala the code is

import play.mvc.Http

val userAgent: String = request.headers.get(Http.HeaderNames.USER_AGENT).get

Solution 3

This line worked for me:

implicit request => val User-Agent:String = request.headers.get("User-Agent").get

Comments

[ticofab]

Thank you nico_ekito! I'd be also very happy if you could you point me to some more extensive guide: the one on the website seems to only scratch the surface.

[ndeverge]

I do not know any particular guide, instead of the official doc. There are also some books out there bit.ly/playscala and bit.ly/playjava

[supertonsky]

Can you please at least provide where request() came from? For novices' sake please.

[ndeverge]

It is inherited from the Controller class