Tester API

Introduction

The Tester Application is one of the key run-time components which comprise the N2SVCD run-time service process. The Tester Application is responsible for executing “Test Runs” on behalf of clients. It is managed via a JSON interface.

Clients (such as the IN Tester GUI) wishing to perform Test Management (e.g. execute/query/cancel test runs) can make their requests over a TCP Remote Procedure Call (RPC) interface. The RPC interface offered by the N2SVCD Tester Application is implemented using the JSON-RPC interface.

By default, the TesterApplication will listen on port 9009 for incoming JSON RPC Test Management requests. This port number may be changed by modifying the relevant configuration parameter as described in the N2SVCD Config - Tester.

The first 4 bytes of any RPC request or response are the message length (in bytes) as an unsigned integer in network byte order. The remainder of the request or response is a JSON structure of exactly the specified number of bytes.

JSON Request - Attributes

The JSON request structure has the following properties:

Note: The general JSON-RPC standard allows for multiple RPC requests on a single TCP connection. However, the JSON-RPC implemented by the N2SVCD Tester Application permits only one JSON Test Management request/response per TCP connection.

JSON Request - Example

An example JSON request could be as follows:

{
   "jsonrpc" : "2.0",
   "id" : 1,
   "method" : "ExecuteTest",
   "params" : {
        "run_id" : "tr_9538",
        "distribution" : {
            "type" : "single"
        },
        "operations" : [
            {
                "type" : "inap.ssp_to_scp.InitialDP",
                "arguments" : {
                    "serviceKey" : 45,
                    "eventTypeBCSM" : 3,
                    "callingPartyNumber_digits" : "414511860"
                }
            },
            {
                "type": "inap.ssp_from_scp.ReleaseCall"
            },
        ],
        "scp" : {
            "dssn" : 106,
            "dpc" : 4114
        }
    }
}

JSON Response - Attributes

The response properties are:

Note: The structure of the params and result objects will vary according to the particular method which is executed. The “result” may be a string, an array, or an object.

The structure of the error object (when present) created by the Tester Application is more consistent. It is always as follows:

JSON Response - Example (Success)

A corresponding success response is:

{
    "jsonrpc" : "2.0",
    "id" : "1",
    "result" : "ok"
}

JSON Response - Example (Error)

A corresponding error response is as follows:

{
    "jsonrpc" : "2.0",
    "id" : "1",
    "error" : {
        "message" : "Unsupported method \"EgsecuteTest\"",
        "code" : 1001
    }
}

Error Codes

The current list of error codes is given here. New error codes may be added at any time without notice.