POSTGRES_DB environment variable not honored during initialization

[adityathebe]

Problem

The flanksource/postgres:17 image does not create the database specified in the POSTGRES_DB environment variable during initialization, unlike standard PostgreSQL images (including supabase/postgres).

Expected Behavior

When POSTGRES_DB is set to a value other than "postgres", that database should exist after the container starts for the first time.

Current Behavior

Only the default databases are created:

• postgres
• template0
• template1

The custom database specified in POSTGRES_DB is not created.

Reproduction

# docker-compose.yaml
services:
  postgres:
    image: ghcr.io/flanksource/postgres:17
    environment:
      POSTGRES_DB: mission_control
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: testpassword
    ports:
      - "5432:5432"

Running docker-compose up and then checking with psql -U postgres -c "\l" shows that mission_control database does not exist.

Impact

This breaks migration from supabase/postgres to flanksource/postgres when using helm charts that rely on POSTGRES_DB to automatically create the application database.

[adityathebe]

#31