Postrgresql need to be started first while using externalDatabase

[Skallwar]

I found that if Postgresql is not running before the nextcloud docker image is launched, I get some weird issues:

Initializing nextcloud 19.0.3.1 ...
Initializing finished
New nextcloud instance
Installing with PostgreSQL database
starting nextcloud installation
PostgreSQL username and/or password not valid
 -> You need to enter details of an existing account.
retrying install...
An unhandled exception has been thrown:
OC\DatabaseException: An exception occurred while executing 'SHOW SERVER_VERSION':
Failed to connect to the database: An exception occurred in driver: SQLSTATE[08006] [7] could not connect to server: Connection refused
	Is the server running on host "nextcloud-postgresql.nextcloud" (10.43.125.77) and accepting
	TCP/IP connections on port 5432? in /var/www/html/lib/private/legacy/OC_DB.php:73
Stack trace:
#0 /var/www/html/lib/private/legacy/OC_DB.php(139): OC_DB::prepare('SHOW SERVER_VER...', NULL, NULL)
#1 /var/www/html/lib/private/legacy/OC_Util.php(971): OC_DB::executeAudited(Array)
#2 /var/www/html/lib/private/legacy/OC_Util.php(951): OC_Util::checkDatabaseVersion()
#3 /var/www/html/lib/private/Console/Application.php(161): OC_Util::checkServer(Object(OC\SystemConfig))
#4 /var/www/html/console.php(99): OC\Console\Application->loadCommands(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#5 /var/www/html/occ(11): require_once('/var/www/html/c...')
#6 {main}retrying install...
An unhandled exception has been thrown:
OC\DatabaseException: An exception occurred while executing 'SHOW SERVER_VERSION':
Failed to connect to the database: An exception occurred in driver: SQLSTATE[08006] [7] could not connect to server: Connection refused
	Is the server running on host "nextcloud-postgresql.nextcloud" (10.43.125.77) and accepting
	TCP/IP connections on port 5432? in /var/www/html/lib/private/legacy/OC_DB.php:73
Stack trace:
#0 /var/www/html/lib/private/legacy/OC_DB.php(139): OC_DB::prepare('SHOW SERVER_VER...', NULL, NULL)
#1 /var/www/html/lib/private/legacy/OC_Util.php(971): OC_DB::executeAudited(Array)
#2 /var/www/html/lib/private/legacy/OC_Util.php(951): OC_Util::checkDatabaseVersion()
#3 /var/www/html/lib/private/Console/Application.php(161): OC_Util::checkServer(Object(OC\SystemConfig))
#4 /var/www/html/console.php(99): OC\Console\Application->loadCommands(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#5 /var/www/html/occ(11): require_once('/var/www/html/c...')
#6 {main}retrying install...

nextcloud-values.yml:

...
externalDatabase:
  enabled: true
  type: postgresql
  host: nextcloud-postgresql.nextcloud:5432
  user: CHANGEME
  password: CHANGEME
  database: nextcloud


postgresql:
  enabled: true
  image:
    registry: docker.io
    repository: postgres
    tag: 13.1
    debug: true
  ...
...

Sometimes I get the setup screen of nextcloud (asking to create a new admin account), sometimes I just get an error code 503 indefinitely.

If I take the same value and I deploy the bitnami postgresql chart manualy (using the same config) and then I deploy nextcloud (with postgresql.enable = false this time) everything works great.
Currently, I have a script which does 2 deployments with a sleep in between to resolve this issue

helm install postgresql bitnami/postgresql --values ./postgresql-values.yml -n nextcloud
sleep 60
helm install nextcloud nextcloud/nextcloud --values ./nextcloud-values.yml -n nextcloud

[lukasmrtvy]

I can confirm, nextcloud installation is broken if external postgresql deployed with this chart is used.
Probably migration script will fail if postgresql is not ready, that will cause problems ^. Something like initContainer with psql and mariadb client that will wait for DB readiness would do the trick, a lot of charts are using this ..

@billimek ping