Vtgateproxy rework register flags

[demmer]

Description

As part of reducing the touch points for vtgateproxy inside the main vitess codebase, change the way that the binary registers the various command line flags so that it explicitly calls the various register functions rather than relying on having the binary name in the internal list.

IMHO this would be a better way for all the vitess binaries to manage registering their flags, as I feel like the hard-coded list of strings feels somewhat odd, but that's a question for the maintainers upstream and doesn't really affect us here.

Testing

Confirmed that the output of vtgateproxy --help is the same before and after the change so this registers all the same flags

Benefits

With this patch in place, the proxy-specific diffs on this branch include:

[mdemmer-ltmzvnq] -> git diff --stat vtgateproxy-v19-base
 go.mod                                           |   8 +-
 go.sum                                           |   9 ++
 go/cmd/vtgateproxy/.gitignore                    |   1 +
 go/cmd/vtgateproxy/vtgateproxy                   | Bin 32493648 -> 0 bytes
 go/cmd/vtgateproxy/vtgateproxy.go                |  68 ++++++++++++++
 go/mysql/conn.go                                 |   5 ++
 go/mysql/constants.go                            |   4 +
 go/mysql/server.go                               |  46 +++++-----
 go/test/endtoend/vtgateproxy/failure_test.go     | 219 ++++++++++++++++++++++++++++++++++++++++++++
 go/test/endtoend/vtgateproxy/main_test.go        | 480 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 go/test/endtoend/vtgateproxy/rebalance_test.go   | 171 +++++++++++++++++++++++++++++++++++
 go/test/endtoend/vtgateproxy/scale_test.go       | 190 +++++++++++++++++++++++++++++++++++++++
 go/test/endtoend/vtgateproxy/vtgateproxy_test.go | 118 ++++++++++++++++++++++++
 go/vt/vtgate/grpcvtgateconn/conn.go              |  18 ++--
 go/vt/vtgate/vtgateconn/vtgateconn.go            |   7 +-
 go/vt/vtgateproxy/discovery.go                   | 519 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 go/vt/vtgateproxy/firstready_balancer.go         | 103 +++++++++++++++++++++
 go/vt/vtgateproxy/mysql_server.go                | 659 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 go/vt/vtgateproxy/sim/go.mod                     |   5 ++
 go/vt/vtgateproxy/sim/go.sum                     |   2 +
 go/vt/vtgateproxy/sim/vtgateproxysim.go          | 101 +++++++++++++++++++++
 go/vt/vtgateproxy/sticky_random_balancer.go      | 110 +++++++++++++++++++++++
 go/vt/vtgateproxy/vtgateproxy.go                 | 246 ++++++++++++++++++++++++++++++++++++++++++++++++++
 test/config.json                                 |   9 ++

With this diff in place, the only upstream changes are those in go/mysql and go/vt/vtgate for which I opened upstream PRs here:

vitessio#18548
vitessio#18551

So between those two changes and the patches in this branch, we should be better positioned to maintain the proxy outside of the main repo.

[jscheinblum]

does this need to be made public? I maybe misunderstand how this works

[jscheinblum]

never mind - ignore me

[demmer]

Ya - This is part of the upstream PR vitessio#18551 and is consistent with a bunch of the other submodules.

That way the vtgateproxy binary can bind the flags in init like it does for the other dependencies it wants to pull in.

[github-actions]

This PR is being marked as stale because it has been open for 30 days with no activity. To rectify, you may do any of the following:

• Push additional commits to the associated branch.
• Remove the stale label.
• Add a comment indicating why it is not stale.

If no action is taken within 7 days, this PR will be closed.

[github-actions]

This PR was closed because it has been stale for 7 days with no activity.