Add Workflow Update Client Command

[mattlord]

Description

This adds a new update action to the Workflow vtctl client command as well as a new Workflow update vtctldclient command. This allows users to easily modify the cells, tablet-types, and on-ddl configuration parameters of a VReplication workflow. There are other parameters — e.g. see the full list of parameters for MoveTables — that we could potentially add in the future, but for now we're starting with the ones that are always safe to set. The others are dependent on the workflow state and other factors so the application of those changes is more complicated and thus they will only be added in the future based on use-case / demand.

This work will allow us to remove the VReplicationExec vtctl client command as updating a workflow was the last remaining use case for it. As an example, using the Workflow update command would then replace the cumbersome VReplicationExec method used to update the cells parameter here: https://vitess.io/docs/16.0/user-guides/migration/troubleshooting/#corrective-action

You can manually test and play around with the command using the local examples:

cd examples/local
./101_initial_cluster.sh; ./201_customer_tablets.sh; ./202_move_tables.sh

command mysql -u root --socket=${VTDATAROOT}/vt_0000000200/mysql.sock --binary-as-hex=false -e "select source,cell,tablet_types from _vt.vreplication where workflow='commerce2customer'\G"

vtctlclient Workflow -- --cells=zone1 --tablet-types="primary" --on-ddl=exec --dry-run customer.commerce2customer update

vtctlclient Workflow -- --cells=zone1 --tablet-types="primary" --on-ddl=exec customer.commerce2customer update

command mysql -u root --socket=${VTDATAROOT}/vt_0000000200/mysql.sock --binary-as-hex=false -e "select source,cell,tablet_types from _vt.vreplication where workflow='commerce2customer'\G"

...

Example vtctldclient command and output:

$ vtctldclient workflow --keyspace=customer update --workflow=commerce2customer --cells="zone1,zone2"
{
  "summary": "Successfully updated the commerce2customer workflow on (1) target primary tablets in the customer keyspace",
  "details": [
    {
      "tablet": "zone1-201 (customer/0)",
      "changed": true
    }
  ]
}

$ vtctldclient workflow --keyspace=customer update --workflow=commerce2customer --cells="zone1,zone2"
{
  "summary": "Successfully updated the commerce2customer workflow on (1) target primary tablets in the customer keyspace",
  "details": [
    {
      "tablet": "zone1-201 (customer/0)",
      "changed": false
    }
  ]
}

$ vtctldclient workflow --keyspace=customer update --workflow=cust2cust --on-ddl=EXEC_IGNORE --cells="zone1,zone2,zone3"
{
  "summary": "Successfully updated the cust2cust workflow on (2) target primary tablets in the customer keyspace",
  "details": [
    {
      "tablet": "zone1-300 (customer/-80)",
      "changed": true
    },
    {
      "tablet": "zone1-400 (customer/80-)",
      "changed": true
    }
  ]
}

Related Issue(s)

• Fixes: Add Edit/Update Action to Workflow Client Command #12303
• Task in: Tracking Issue: Replace VReplicationExec Command + RPC  #12086

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: Document new Workflow update client command website#1409

[vitess-bot]

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[mattlord]

Thank you for the very helpful review @ajm188 ! I believe that I've addressed all of your comments now.

[ajm188]

one question about the any, but i'll approve in case there's no follow-up needed

[ajm188]

just formally 👍-ing again

[rohit-nayak-ps]

lgtm

[ajm188]

added tests lgtm as well

[rohit-nayak-ps]

e2e test changes look good.

[ajm188]

🚢 🚢 🚢