# Which Problems Are Solved
When running a long-running Zitadel Setup, Kubernetes might decide to
move a pod to a new node automatically. Currently, this puts any
migrations into a broken state that an operator needs to manually run
the "cleanup" command on - assuming they catch the error.
The only super long running commands are typically projection pre-fill
operations, which depending on the size of the event table for that
projection, can take many hours - plenty of time for Kubernetes to make
unexpected decisions, especially in a busy cluster.
# How the Problems Are Solved
This change listens on `os.Interrupt` and `syscall.SIGTERM`, cancels the
current Setup context, and runs the `Cleanup` command. The logs then
look something like this:
```shell
...
INFO[0000] verify migration caller="/Users/zach/src/zitadel/internal/migration/migration.go:43" name=repeatable_delete_stale_org_fields
INFO[0000] starting migration caller="/Users/zach/src/zitadel/internal/migration/migration.go:66" name=repeatable_delete_stale_org_fields
INFO[0000] execute delete query caller="/Users/zach/src/zitadel/cmd/setup/39.go:37" instance_id=281297936179003398 migration=repeatable_delete_stale_org_fields progress=1/1
INFO[0000] verify migration caller="/Users/zach/src/zitadel/internal/migration/migration.go:43" name=repeatable_fill_fields_for_instance_domains
INFO[0000] starting migration caller="/Users/zach/src/zitadel/internal/migration/migration.go:66" name=repeatable_fill_fields_for_instance_domains
----- SIGTERM signal issued -----
INFO[0000] received interrupt signal, shutting down: interrupt caller="/Users/zach/src/zitadel/cmd/setup/setup.go:121"
INFO[0000] query failed caller="/Users/zach/src/zitadel/internal/eventstore/repository/sql/query.go:135" error="timeout: context already done: context canceled"
DEBU[0000] filter eventstore failed caller="/Users/zach/src/zitadel/internal/eventstore/handler/v2/field_handler.go:155" error="ID=SQL-KyeAx Message=unable to filter events Parent=(timeout: context already done: context canceled)" projection=instance_domain_fields
DEBU[0000] unable to rollback tx caller="/Users/zach/src/zitadel/internal/eventstore/handler/v2/field_handler.go:110" error="sql: transaction has already been committed or rolled back" projection=instance_domain_fields
INFO[0000] process events failed caller="/Users/zach/src/zitadel/internal/eventstore/handler/v2/field_handler.go:72" error="ID=SQL-KyeAx Message=unable to filter events Parent=(timeout: context already done: context canceled)" projection=instance_domain_fields
DEBU[0000] trigger iteration caller="/Users/zach/src/zitadel/internal/eventstore/handler/v2/field_handler.go:73" iteration=0 projection=instance_domain_fields
ERRO[0000] migration failed caller="/Users/zach/src/zitadel/internal/migration/migration.go:68" error="ID=SQL-KyeAx Message=unable to filter events Parent=(timeout: context already done: context canceled)" name=repeatable_fill_fields_for_instance_domains
ERRO[0000] migration finish failed caller="/Users/zach/src/zitadel/internal/migration/migration.go:71" error="context canceled" name=repeatable_fill_fields_for_instance_domains
----- Cleanup before exiting -----
INFO[0000] cleanup started caller="/Users/zach/src/zitadel/cmd/setup/cleanup.go:30"
INFO[0000] cleanup migration caller="/Users/zach/src/zitadel/cmd/setup/cleanup.go:47" name=repeatable_fill_fields_for_instance_domains
```
# Additional Changes
* `mustExecuteMigration` -> `executeMigration`: **must**Execute logged a
Fatal error previously which calls os.Exit so no cleanup was possible.
Instead, this PR returns an error and assigns it to a shared error in
the Setup closure that defer can check.
* `initProjections` now returns an error instead of exiting
# Additional Context
This behavior might be unwelcome or at least unexpected in some cases.
Putting it behind a feature flag or config setting is likely a good
followup.
---------
Co-authored-by: Silvan <[email protected]>
# Which Problems Are Solved
- `pgxpool -> pgx` dependency throws "MaxSize must be >= 1" on init if
`postgres.MaxOpenConns` isn't set in the ZItadel config
# How the Problems Are Solved
Only override the `MaxConns` with the Zitadel configured `MaxOpenConns`
if greater than 0 (default value). The default `MaxConns` [is derived by
`pgxpool`](https://github.com/jackc/pgx/blob/ea9610f6722e0c6c6073660f14ded3c9683a593e/pgxpool/pool.go#L309-L324)
itself in a sensible way, but somewhat undocumented: checks for explicit
config in connection url or config and falls back on max(num_cpus, 4).
# Additional Changes
Applied same check in cockroach config
# Additional Context
This is likely a regression from the changes in
https://github.com/zitadel/zitadel/pull/8325
