Fix several test flakes:
- test_sharding_service_smoke had log failures on "Dropped LSN updates"
- test_emergency_mode had log failures on a deletion queue shutdown
check, where the check was incorrect because it was expecting channel
receiver to stay alive after cancellation token was fired.
- test_secondary_mode_eviction had racing heatmap uploads because the
test was using a live migration hook to set up locations, where that
migration was itself uploading heatmaps and generally making the
situation more complex than it needed to be.
These are the failure modes that I saw when spot checking the last few
failures of each test.
This will mostly/completely address #6511, but I'll leave that ticket
open for a couple days and then check if either of the tests named in
that ticket are flaky.
Related #6511
Cleanups from https://github.com/neondatabase/neon/pull/6394
- There was a rogue `*` breaking the `GET /tenant/:tenant_id`, which
passes through to shard zero
- There was a duplicate migrate endpoint
- There are un-prefixed API endpoints that were only needed for compat
tests and can now be removed.
## Problem
When we change which physical pageservers a tenant is attached to, we
must update the control plane so that it can update computes. This will
be done via an HTTP hook, as described in
https://www.notion.so/neondatabase/Sharding-Service-Control-Plane-interface-6de56dd310a043bfa5c2f5564fa98365#1fe185a35d6d41f0a54279ac1a41bc94
## Summary of changes
- Optional CLI args `--control-plane-jwt-token` and `-compute-hook-url`
are added. If these are set, then we will use this HTTP endpoint,
instead of trying to use neon_local LocalEnv to update compute
configuration.
- Implement an HTTP-driven version of ComputeHook that calls into the
configured URL
- Notify for all tenants on startup, to ensure that we don't miss
notifications if we crash partway through a change, and carry a
`pending_compute_notification` flag at runtime to allow notifications to
fail without risking never sending the update.
- Add a test for all this
One might wonder: why not do a "forever" retry for compute hook
notifications, rather than carrying a flag on the shard to call
reconcile() again later. The reason is that we will later limit
concurreny of reconciles, when dealing with larger numbers of shards,
and if reconcile is stuck waiting for the control plane to accept a
notification request, it could jam up the whole system and prevent us
making other changes. Anyway: from the perspective of the outside world,
we _do_ retry forever, but we don't retry forever within a given
Reconciler lifetime.
The `pending_compute_notification` logic is predicated on later adding a
background task that just calls `Service::reconcile_all` on a schedule
to make sure that anything+everything that can fail a
Reconciler::reconcile call will eventually be retried.
Depends on: https://github.com/neondatabase/neon/pull/6468
## Problem
The sharding service will be used as a "virtual pageserver" by the
control plane -- so it needs the set of pageserver APIs that the control
plane uses, and to present them under identical URLs, including prefix
(/v1).
## Summary of changes
- Add missing APIs:
- Tenant deletion
- Timeline deletion
- Node list (used in test now, later in tools)
- `/location_config` API (for migrating tenants into the sharding
service)
- Rework attachment service URLs:
- `/v1` prefix is used for pageserver-compatible APIs
- `/upcall/v1` prefix is used for APIs that are called by the pageserver
(re-attach and validate)
- `/debug/v1` prefix is used for endpoints that are for testing
- `/control/v1` prefix is used for new sharding service APIs that do not
mimic a pageserver API, such as registering and configuring nodes.
- Add test_sharding_service. The sharding service already had some
collateral coverage from its use in general tests, but this is the first
dedicated testing for it.
