ScalaXmlRequests

Handling and serving Xml requests

Handling an Xml request

An Xml request is an HTTP request using a valid Xml payload as request body. It must specify the text/xml mime type in its Content-Type header.

By default an Action uses a any content body parser. Then you can ask to retrieve the body as Xml (actually as a NodeSeq):

def sayHello = Action { request =>
  request.body.asXml.map { xml =>
    (xml \\ "name" headOption).map(_.text).map { name =>
      Ok("Hello " + name)
    }.getOrElse {
      BadRequest("Missing parameter [name]")
    }
  }.getOrElse {
    BadRequest("Expecting Xml data")
  }
}

Of course it's way better (and simpler) to specify our own BodyParser to ask Play to parser the content body directly as Xml:

def sayHello = Action(parse.xml) { request =>
  (request.body \\ "name" headOption).map(_.text).map { name =>
    Ok("Hello " + name)
  }.getOrElse {
    BadRequest("Missing parameter [name]")
  }
}

Note: When using a xml body parser, the request.body value is directly a valid NodeSeq.

You can test it with cUrl from a command line:

curl 
  --header "Content-type: text/xml" 
  --request POST 
  --data '<name>Guillaume</name>' 
  http://localhost:9000/sayHello

It replies with:

HTTP/1.1 200 OK
Content-Type: text/plain; charset=utf-8
Content-Length: 15

Hello Guillaume

Serving an Xml response

In our previous example we handle an Xml request, but we reply with a text/plain response. Let'as change that to send back a valid Xml HTTP response:

def sayHello = Action(parse.xml) { request =>
  (request.body \\ "name" headOption).map(_.text).map { name =>
    Ok(<message status="OK">Hello {name}</message>)
  }.getOrElse {
    BadRequest(<message status="KO">Missing parameter [name]</message>)
  }
}

Now it replies with:

HTTP/1.1 200 OK
Content-Type: text/xml; charset=utf-8
Content-Length: 46

<message status="OK">Hello Guillaume</message>

Next: Handling file upload