GoSnappi: existing node of input json is updated by FromJSON with defaults

[rudranil-das]

Observation from Snappi version: 0.6.5

Let me illustrate this with an example of - rate node of input json being updated by FromJSON (of gosnappi.Config) with defaults [i.e. "choice":1,"pps":1000].

Input json to (gosnappi.Config->)FromJSON

flows": [
    {
      "duration": {
        "choice": "fixed_packets",
        "fixed_packets": {
          "gap": 12,
          "packets": 50000
        }
      },
      "name": "flw",
      "packet": [
        {
          "choice": "ethernet",
          "ethernet": {}
        },
        {
          "choice": "ipv4",
          "ipv4": {}
        },
        {
          "choice": "tcp",
          "tcp": {
            "dst_port": {
              "choice": "values",
              "values": [
                3000,
                3010,
                3030
              ]
            },
            "src_port": {
              "choice": "increment",
              "increment": {
                "count": 501,
                "start": 5000,
                "step": 2
              }
            }
          }
        }
      ],
      "rate": {
        "choice": "percentage",
        "percentage": 10
      },
      "size": {
        "choice": "fixed",
        "fixed": 1518
      },
      "tx_rx": {
        "choice": "port",
        "port": {
          "tx_name": "tx"
        }
      }
    }
  ],
  "layer1": [
    {
      "auto_negotiate": true,
      "ieee_media_defaults": true,
      "mtu": 1600,
      "name": "l1",
      "port_names": [
        "tx"
      ],
      "promiscuous": true,
      "speed": "speed_1_gbps"
    }
  ],
  "ports": [
    {
      "location": "10.39.32.156:5555",
      "name": "tx"
    }
  ]
}   

Output object dump from (gosnappi.Config->)FromJSON is

{
   "ports":[
      {
         "location":"10.39.32.156:5555",
         "name":"tx"
      }
   ],
   "layer1":[
      {
         "port_names":[
            "tx"
         ],
         "speed":5,
         "promiscuous":true,
         "mtu":1600,
         "ieee_media_defaults":true,
         "auto_negotiate":true,
         "name":"l1"
      }
   ],
   "flows":[
      {
         "tx_rx":{
            "choice":1,
            "port":{
               "tx_name":"tx"
            }
         },
         "packet":[
            {
               "choice":2,
               "ethernet":{

               }
            },
            {
               "choice":5,
               "ipv4":{

               }
            },
            {
               "choice":9,
               "tcp":{
                  "src_port":{
                     "choice":3,
                     "value":0,
                     "increment":{
                        "start":5000,
                        "step":2,
                        "count":501
                     }
                  },
                  "dst_port":{
                     "choice":1,
                     "value":0,
                     "values":[
                        3000,
                        3010,
                        3030
                     ]
                  }
               }
            }
         ],
         "size":{
            "choice":1,
            "fixed":1518
         },
         "rate":{
            "choice":1,
            "pps":1000,
            "percentage":10
         },
         "duration":{
            "choice":1,
            "fixed_packets":{
               "packets":50000,
               "gap":12
            }
         },
         "name":"flw"
      }
   ]
}

If you look at the "rate" block, "choice" is reset to "1" [which is PPS] and "pps" = 1000 attribute is added.

I think setdefaults in workflow of FromJSON is causing this (but you can validate the same)

Similar issue is observed for FromJSON in following cases:

1. protocol header fields: "values" cases where choice is unmarshalled as "value", and default value of "value" field is assigned.

2. Other constructs like FlowDelay, FlowDurationInterBurstGap (could be in other places as well)

3. Constructs (like mentioned above) for other gosnappi APIs like FlowsUpdate

[rudranil-das]

This is a high priority issue for gosnappi integration in ixia-c as it is blocking 40+ E2E sanity-cases. @arkajyoti-cloud

[ashutshkumr]

@Rangababu-R I see multiple problems with JSON deserialization here. Let's break it up into multiple issues if needed.

[Rangababu-R]

looks like there is an issue with setDefaults. will fix and get back on this