Postgres 18

[s01ipsist]

Adds support for Postgres 18 by adding conditional logic to set the data volume path differently for before/after v 18, as guided by https://hub.docker.com/_/postgres

The defined VOLUME was changed in 18 and above to /var/lib/postgresql. Mounts and volumes should be targeted at the updated location

Important Note: (for PostgreSQL 17 and below) Mount the data volume at /var/lib/postgresql/data and not at /var/lib/postgresql because mounts at the latter path WILL NOT PERSIST database data when the container is re-created

Fixes #364
Replaces #358 / #367

Not sure if this needs to be fixed or not, but there's a subtle functional change in the result with this code as is.

• v17 service stays running after creation
• v18 service stops after creation, and requires a separate call to dokku postgres:start to re-start service
  This appears to be because of the logic in
  https://github.com/docker-library/postgres/blob/master/docker-entrypoint.sh#L360
  v17 triggers the path with message output

PostgreSQL Database directory appears to contain a database; Skipping initialization

v18 triggers the path with message output

PostgreSQL init process complete; ready for start up.

and stops the container.

[josegonzalez]

Whats the entire output of an initial dokku postgres:create with v18 today?

[s01ipsist]

Whats the entire output of an initial dokku postgres:create with v18 today?

ubuntu@multidokku25:~$ dokku plugin:list | grep postgres
  postgres             1.45.0 enabled    dokku postgres service plugin
ubuntu@multidokku25:~$ dokku postgres:create pg18test --image-version 18.1
18.1: Pulling from library/postgres
b89cf3ec7a3e: Pull complete
3d40ad1ee517: Pull complete
5e86690e08b4: Pull complete
36aea44977d6: Pull complete
af5b2941599b: Pull complete
e808f1e529cf: Pull complete
07c5a27f4144: Pull complete
d84932fbe51d: Pull complete
87e5f1d7b994: Pull complete
477d35ab7c57: Pull complete
c598951473cf: Pull complete
55bb4e0a9b60: Pull complete
4aee7b1337ee: Pull complete
Digest: sha256:5ec39c188013123927f30a006987c6b0e20f3ef2b54b140dfa96dac6844d883f
Status: Downloaded newer image for postgres:18.1
docker.io/library/postgres:18.1
       Waiting for container to be ready
       Creating container database
       Securing connection to database
ubuntu@multidokku25:~$ dokku postgres:info pg18test
=====> pg18test postgres service information
       Config dir:          /var/lib/dokku/services/postgres/pg18test/data
       Config options:
       Data dir:            /var/lib/dokku/services/postgres/pg18test/data
       Dsn:                 postgres://postgres:2f6f0c006b10032d2279fa0314fccb51@dokku-postgres-pg18test:5432/pg18test
       Exposed ports:       -
       Id:                  fe1988ffa73c5e1b33e477ba5303ac60bede64f53aa246ad64fc8943b3c4f43e
       Internal ip:
       Initial network:
       Links:               -
       Post create network:
       Post start network:
       Service root:        /var/lib/dokku/services/postgres/pg18test
       Status:              exited
       Version:             postgres:18.1

[josegonzalez]

Atm it looks like all tests fail because the :create command fails. That needs to work and create a running container. What changes would be necessary to do that?

[s01ipsist]

Atm it looks like all tests fail because the :create command fails. That needs to work and create a running container. What changes would be necessary to do that?

Have added a change that tries to ensure the container is running after create

[josegonzalez]

Yeah create still exits 0. I'll have to take a look at this tomorrow and see whats going on locally.

[s01ipsist]

I see now that it's the call in scripts/enable_ssl.sh which errors (silently)

bash: line 5: cd: /var/lib/postgresql/data: No such file or directory

so the following call in functions to
suppress_output "$DOCKER_BIN" container start "$(cat "$SERVICE_ROOT/ID")"
never gets called.

This "Securing connection to database" section needs a matching fix 🤔

[s01ipsist]

We can use the PGDATA env var set in the upstream image.
https://github.com/docker-library/postgres/blob/9c515320bc6aa1243585763eb1696118969ffef0/Dockerfile-alpine.template#L221
This works for 18 and <18.

$ dokku postgres:create postgres18_test --image-version 18.0
       Waiting for container to be ready
       Creating container database
       Securing connection to database
=====> Postgres container created: postgres18_test
=====> postgres18_test postgres service information
       Config dir:          /var/lib/dokku/services/postgres/postgres18_test/data
       Config options:
       Data dir:            /var/lib/dokku/services/postgres/postgres18_test/data
       Dsn:                 postgres://postgres:7b5e5f8b9ce4bc429a36a984051f13f3@dokku-postgres-postgres18-test:5432/postgres18_test
       Exposed ports:       -
       Id:                  fb594e1636fec8de24f39a1328a08f9359affd54b0ee8c502ea188b6ff901ac0
       Internal ip:         172.17.0.7
       Initial network:
       Links:               -
       Post create network:
       Post start network:
       Service root:        /var/lib/dokku/services/postgres/postgres18_test
       Status:              running
       Version:             postgres:18.0
$ dokku postgres:connect postgres18_test
psql (18.0 (Debian 18.0-1.pgdg13+3))
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, compression: off, ALPN: postgresql)
Type "help" for help.

postgres18_test=# \q

[josegonzalez]

Thanks for the pull request!