Message queues

General description

It is possible to connect to message queues for:

1. receiving responses for asynchronous tasks;

2. receiving events from agents located in restaurants (agent events).

Connection procedure

Connection to the queue is performed using the long polling method. The aggregator needs to perform a Post request to the address:

POST https://{{serverName}}/wsserverlp/api/v2/aggregators/ListenQueue

If there is a message, you will receive an answer immediately. If there is no message, Whiteserver will hold the connection until a message is received or 20 seconds have passed. Then the aggregator must re-establish the connection.

The request body must specify the queue type.

Request format:

{
  "queueType": "enum string"
}

Response parsing sequence

1. Check for the presence of an 'error' branch. If it is not there, proceed with parsing successfully. If it exists, parse the error.

2. Check for the presence of a 'responseCommon' branch. If it exists, everything is fine, continue parsing. If it does not exist, then there's an error.

3. In the 'responseCommon' branch, check for the presence of 'asyncCode': 'NoOperations'. If it exists, it means there are no new tasks/events. If it doesn't exist, it means there is a response. Parse further.

4. In the "responseCommon" branch parse "taskType".

4.1. If "taskType" = "Event", then parse the "eventResponse" branch and use the restaurant identifier objectId.

4.2. Otherwise, "taskType" = one of the commands. i.e. parse the "taskResponse" branch.

Response — If there is no data

{
  "responseCommon": {
    "asyncCode": "NoOperations"
  }
}

Response - If a response has been received for a task

Successful response to the task

{
  "taskResponse": {
  ----------task response json---------
  },
  "responseCommon": {
    "taskGuid": "guid string",
    "taskType": "enum string",
    "objectId": int
  }
}

Response to the task with an error

{
   "responseCommon": {
      "taskGuid": "guid string",
      "taskType": "enum string",
      "objectId": int
   },
   "error": {
         ----------error response json---------
   }
}

Description of parameters

Response - Agent event

{
  "eventResponse": {
  ----------agent event response json---------
  },
  "responseCommon": {
    "taskType": "Event",
    "objectId": int
  },
  "error": {
      ----------error response json---------
  }
}

Description of parameters

Response with error

Example: If there is no authorization, the following will be returned:

{
  "error": {
    "wsError": {
      "code": "error code string"
    }
  }
}

Description of parameters