Add Meta on ConsulTerminatingConfigEntry

[Sol-Stiep]

Description

Changes

• Added support for ConsulTerminatingConfigEntry meta configuration:
  • Added Meta field to ConsulTerminatingConfigEntry struct and updated its receiver functions.
• Updated jobspec/parse_service.go
• Update related tests
• Update Nomad Documentation for ConsulTerminatingConfigEntry struct.

Testing Changes

To test these changes you need to build a Nomad binary and deploy a cluster with both Nomad and Consul agents and clients.
When you have your cluster running you can run the following job-spec:

job "countdash-terminating" {

  datacenters = ["dc1"]

  group "api" {
    network {
      mode = "host"
      port "port" {
        static = "9001"
      }
    }
    
    service {
      name = "count-api"
      port = "port"
    }

    task "api" {
      driver = "docker"

      config {
        image        = "hashicorpdev/counter-api:v3"
        network_mode = "host"
      }
    }
  }

  group "gateway" {
    network {
      mode = "bridge"
    }

    service {
      name = "api-gateway"

      connect {
        gateway {          
          proxy {}     
         
          terminating {          
            service {
              name = "count-api"
            }
            
            # New Fields:
            meta {
              test-key = "test-value"
              test-key1 = "test-value1"
              test-key2 = "test-value2"
            }
          }
        }
      }
    }
  }
  group "dashboard" {
    network {
      mode = "bridge"

      port "http" {
        static = 9002
        to     = 9002
      }
    }

    service {
      name = "count-dashboard"
      port = "9002"

      connect {
        sidecar_service {
          proxy {
            upstreams {              
              destination_name = "count-api"
              local_bind_port  = 8080
            }
          }
        }
      }
    }

    task "dashboard" {
      driver = "docker"

      env {
        COUNTING_SERVICE_URL = "http://${NOMAD_UPSTREAM_ADDR_count_api}"
      }

      config {
        image = "hashicorpdev/counter-dashboard:v3"
      }
    }
  }
}

Once the job is running and healthy, use Consul's API to get the terminating gateway's configuration:

curl --request GET http://127.0.0.1:8500/v1/config/terminating-gateway | json_pp

You will get the following JSON output:

[
   {
      "Meta" : {
         "test-key" : "test-value",
         "test-key1" : "test-value1",
         "test-key2" : "test-value2"
      },
      "Name" : "api-gateway",
      "Services" : [
         {
            "Name" : "count-api"
         }
      ],
      "CreateIndex" : 155,
      "Kind" : "terminating-gateway",
      "ModifyIndex" : 155
   }
]

Demo Video

ConsulTerminatingGatewayConfigEntry.mp4

[tgross]

We didn't land this work when we did our big Consul refresh as it wasn't at the top of priority queue and was going to need rework to merge anyways. Given the current roadmap it doesn't make sense to try to ship these changes unless its in response to a specific request, so I'm going to close this out (and the other 2 similar PRs).