Two changes to deploy/entrypoint.sh, both needed before the app can run
under Docker Swarm without re-triggering known incidents:
One-shot migrate mode: `entrypoint.sh migrate` (or THERMOGRAPH_MIGRATE_ONLY=1)
runs the Alembic migration and exits, for a Swarm one-shot task that brings
the schema to head once rather than racing it across every web replica's
boot. RUN_MIGRATIONS=0 skips the inline migrate for a deploy that runs the
one-shot task separately. Default (unset) keeps today's behavior unchanged:
every boot migrates itself before serving.
Secrets shim: the app reads config from os.environ everywhere (an unset
THERMOGRAPH_AUTH_SECRET falls back to a random per-process value; an unset
VAPID key pair is freshly minted) - Swarm `secrets:` mount each secret as a
FILE under /run/secrets/ instead, which the app would never see. Before
alembic/uvicorn, mechanically export each /run/secrets/<name> whose
uppercased name is a THERMOGRAPH_* var, unless already set in the process
env; THERMOGRAPH_DATABASE_URL is built from a postgres_password secret the
same way compose's own interpolation builds it today.
Verified against fake alembic/uvicorn binaries in a throwaway container:
default boot, migrate-only mode (both trigger forms), RUN_MIGRATIONS=0,
secrets populating unset vars, an existing env var beating its secret file,
and no /run/secrets present at all (today's plain compose path, unaffected).
shellcheck clean.
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