[vtadmin-api] Add HTTP endpoints for /api/srvvschemas and /api/srvvschema/{cluster}/{cell}

[doeg]

Signed-off-by: Sara Bee 855595+doeg@users.noreply.github.com

Description

This adds two new endpoints to vtadmin-api:

• /api/srvvschemas[?cluster=...&cell=...], which returns the SrvVSchema for all clusters and all cells, optionally filtered by a subset of clusters/cells
• /api/srvvschema/{cluster}/{cell}, which returns the SrvVSchema for a particular cell.

curl -s "http://localhost:14200/api/srvvschemas" | jq .

{
  "result": {
    "srv_v_schemas": [
      {
        "cell": "zone1",
        "cluster": {
          "id": "local",
          "name": "local"
        },
        "srv_v_schema": {
          "keyspaces": {
            "commerce": {
              "tables": {
                "customer_seq": {
                  "type": "sequence"
                },
                "order_seq": {
                  "type": "sequence"
                },
                "product": {}
              }
            },
            "customer": {
              "sharded": true,
              "vindexes": {
                "hash": {
                  "type": "hash"
                }
              },
              "tables": {
                "corder": {
                  "column_vindexes": [
                    {
                      "column": "customer_id",
                      "name": "hash"
                    }
                  ],
                  "auto_increment": {
                    "column": "order_id",
                    "sequence": "order_seq"
                  }
                },
                "customer": {
                  "column_vindexes": [
                    {
                      "column": "customer_id",
                      "name": "hash"
                    }
                  ],
                  "auto_increment": {
                    "column": "customer_id",
                    "sequence": "customer_seq"
                  }
                }
              }
            }
          },
          "routing_rules": {}
        }
      }
    ]
  },
  "ok": true
}

curl -s "http://localhost:14200/api/srvvschemas?cluster=nope" | jq .

{
  "result": {},
  "ok": true
}

curl -s "http://localhost:14200/api/srvvschemas?cell=nope" | jq .

{
  "result": {},
  "ok": true
}

curl -s "http://localhost:14200/api/srvvschema/local/zone1" | jq .

{
  "result": {
    "cell": "zone1",
    "cluster": {
      "id": "local",
      "name": "local"
    },
    "srv_v_schema": {
      "keyspaces": {
        "commerce": {
          "tables": {
            "customer_seq": {
              "type": "sequence"
            },
            "order_seq": {
              "type": "sequence"
            },
            "product": {}
          }
        },
        "customer": {
          "sharded": true,
          "vindexes": {
            "hash": {
              "type": "hash"
            }
          },
          "tables": {
            "corder": {
              "column_vindexes": [
                {
                  "column": "customer_id",
                  "name": "hash"
                }
              ],
              "auto_increment": {
                "column": "order_id",
                "sequence": "order_seq"
              }
            },
            "customer": {
              "column_vindexes": [
                {
                  "column": "customer_id",
                  "name": "hash"
                }
              ],
              "auto_increment": {
                "column": "customer_id",
                "sequence": "customer_seq"
              }
            }
          }
        }
      },
      "routing_rules": {}
    }
  },
  "ok": true
}

curl -s "http://localhost:14200/api/srvvschema/no/nope" | jq .

{
  "error": {
    "message": "unsupported cluster(s): no",
    "code": "unknown"
  },
  "ok": false
}

curl -s "http://localhost:14200/api/srvvschema/local/nope" | jq .

{
  "error": {
    "message": "rpc error: code = Unknown desc = node doesn't exist: /vitess/global/cells/nope/CellInfo",
    "code": "unknown"
  },
  "ok": false
}

Related Issue(s)

This is second half of #8221. 🐈

Checklist

• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

N/A

[ajm188]

lgtm