Bug: PostgreSQL Docker Compose template passes invalid DB value to Temporal server

[incidunt]

Description

When generating a project with PostgreSQL enabled and running:

docker compose up

Temporal fails to start with:

Unsupported driver specified: 'DB=postgresql'.
Valid drivers are: mysql8, postgres12, postgres12_pgx, cassandra

Location

Template file:

template/docker-compose.yml.jinja

Around line 91:

DB: postgresql

(or equivalent generated environment variable)

Source:

django-keel/template/docker-compose.yml.jinja

Line 91 in 1afe441

- DB=postgresql

Root Cause

The Temporal auto-setup image does not accept postgresql as a valid database driver value.

Supported values are:

• postgres12
• postgres12_pgx
• mysql8
• cassandra

As documented in the official Temporal Docker Compose example:

https://github.com/temporalio/samples-server/blob/ca1106b647c34323876bd6f221f4310271096dd8/compose/docker-compose-postgres.yml#L49

which uses:

DB: postgres12

Steps to Reproduce

1. Generate a new Django Keel project with PostgreSQL enabled.
2. Run:

docker compose up

3. Observe Temporal startup failure:

Unsupported driver specified: 'DB=postgresql'
Valid drivers are: mysql8, postgres12, postgres12_pgx, cassandra

Expected Behavior

Temporal should start successfully using PostgreSQL.

Suggested Fix

Replace:

DB: postgresql

with:

DB: postgres12

(or postgres12_pgx if pgx is preferred)

to match Temporal's supported driver names.

Additional Context

The generated Django configuration correctly uses postgresql, but Temporal's Docker image expects a different identifier for the database backend. This causes the generated Docker Compose stack to fail immediately on first startup.