anchor.diff:  + Body (application/json)
   
           {
  -          "jsonrpc":"2.0",
  -          "id":5,
  -          "result": {
  -            "sessionId":"c93e5bf0-4fd0-4888-9411-765ff5d89b93"
  -          }
  +            "id": 38,
  +            "result": {
  +                "sessionId": "bd4d6227-0463-4d52-b1c3-c71f0be68466"
  +            },
  +            "jsonrpc": "2.0"
           }
   
   ## Group OnEvent
   
  -When a client is `subscribed` to a type of events in an object, the server sends an onEvent request each time an event of that type is fired in the object. This is possible because the Stream Oriented open API is implemented with websockets and there is a full duplex channel between client and server. The request that server send to client has all the information about the event:
  -
  -* `data`: Information about this specific of this type of event.
  -* `source`: the object source of the event.
  -* `type`: The type of the event.
  -* `subscription`: subscription id for which the event is fired.
  +When a client is `subscribed` to a type of events in an object, the server sends an onEvent request each time an event of that type is fired in the object. This is possible because the Stream Oriented open API is implemented with WebSockets and there is a full duplex channel between client and server.
   
   ### Request
   
  
positive.code: 
  ### Request
  
  A `subscribe` reqest contains the following parameters:
  
  * `method` (required, string). Value is `subscribe`.
  * `params` (required, object). Parameters for the invocation of the create message, containing these members:
      * `constructorParams` (required, object). Additional parameters. As minimum, the identifier of the media pipeline should be included here.
          * `type` (required, string). Media event to be subscribed. Allowed Values:
              * `CodeFound Event`: raised by a ZBarFilter when a code is found in the data being streamed.
              * `ConnectionStateChanged`: Indicates that the state of the connection has changed.
              * `ElementConnected`: Indicates that an element has been connected to other.
              * `ElementDisconnected`: Indicates that an element has been disconnected.
              * `EndOfStream`: Event raised when the stream that the element sends out is finished.
              * `Error`: An error related to the MediaObject has occurred.
              * `MediaSessionStarted`: Event raised when a session starts. This event has no data.
              * `MediaSessionTerminated`: Event raised when a session is terminated. This event has no data.
              * `MediaStateChanged`: Indicates that the state of the media has changed.
              * `ObjectCreated`: Indicates that an object has been created on the mediaserver.
              * `ObjectDestroyed`: Indicates that an object has been destroyed on the mediaserver.
              * `OnIceCandidate`: Notify of a new gathered local candidate.
              * `OnIceComponentStateChanged`: Notify about the change of an ICE component state.
              * `OnIceGatheringDone`: Notify that all candidates have been gathered.
      * `sessionId` (required, string). Session identifier.
  
  The following example shows a request message requesting the subscription of the event type `EndOfStream` on the object `311861480`. The `sessionId` is also included:
  
  + Body (application/json)
  
          {
            "jsonrpc":"2.0",
            "id":4,
            "method":"subscribe",
            "params":{
              "object":"311861480",
              "type":"EndOfStream",
              "sessionId":"c93e5bf0-4fd0-4888-9411-765ff5d89b93"
            }
          }
  
  ### Response
  
negative.code: 
  * `result` (required, object)
      * `sessionId` (required, string). Session identifier.
      * `value` (optional, object). Additional object which describes the result of the `Invoke` operation. For example, in a `WebRtcEndpoint` this field is the SDP response (WebRTC SDP negotiation).
  
  The following example shows a typical response while invoking the operation connect:
  
  + Body (application/json)
  
          {
              "id": 5,
              "result": {
                  "sessionId": "bd4d6227-0463-4d52-b1c3-c71f0be68466"
              },
              "jsonrpc": "2.0"
          }
  
  ## Group Release
  