VReplication: Add traffic state to vtctldclient workflow status output

[mattlord]

Description

This offers an equivalent to the undocumented vtctlclient <workflow type> GetState command for VReplication workflows in vtctldclient.

Example output:

❯ vtctlclient MoveTables getstate customer.commerce2customer
Reads partially switched. Replica not switched. All Rdonly Reads Switched. Writes Not Switched


❯ vtctldclient MoveTables --workflow commerce2customer --target-keyspace customer status
The following vreplication streams exist for workflow customer.commerce2customer:

id=1 on customer/zone1-200: Status: Running. VStream Lag: 0s.

Traffic State: Reads partially switched. Replica not switched. All Rdonly Reads Switched. Writes Not Switched


❯ vtctldclient MoveTables --workflow commerce2customer --target-keyspace customer status --format=json
{
  "table_copy_state": {},
  "shard_streams": {
    "customer/0": {
      "streams": [
        {
          "id": 1,
          "tablet": {
            "cell": "zone1",
            "uid": 200
          },
          "source_shard": "commerce/0",
          "position": "2e6fcd02-6ab0-11ee-bf4a-de2a399f725d:1-59",
          "status": "Running",
          "info": "VStream Lag: 0s"
        }
      ]
    }
  },
  "traffic_state": "Reads partially switched. Replica not switched. All Rdonly Reads Switched. Writes Not Switched"
}

❯ vtctldclient MoveTables --workflow commerce2customer --target-keyspace customer status --format=json --compact
{
  "shard_streams": {
    "customer/0": {
      "streams": [
        {
          "id": 1,
          "tablet": {
            "cell": "zone1",
            "uid": 200
          },
          "source_shard": "commerce/0",
          "position": "ed7d86b6-6af2-11ee-830a-d1f96a268113:1-59",
          "status": "Running",
          "info": "VStream Lag: 0s"
        }
      ]
    }
  },
  "traffic_state": "Reads partially switched. Replica not switched. All Rdonly Reads Switched. Writes Not Switched"
}

Related Issue(s)

• Fixes: Feature Request: Add MoveTables GetState functionality to v19 vtctldclient #14279

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on the CI
• Documentation: Replace all vtctlclient usage for vreplication commands website#1619

[vitess-bot]

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