Modern Perl Catalyst: Docker Setup - Update

Based on feedback from one of my previous blogs and updates to community project I made a few changes.

First Sqitch released an update that supported Perl 5.38 so I updated the application container to use that. I also had a discussion with the author and he suggested using default environment variables rather than building the sqitch configuration file over and over. So I updated that config file to look like:

[core]
    engine = pg
    top_dir = sql
    target = main
[target "main"]
    uri = db:pg:

and changed the Makefile to map the incoming environment variables that define how to access the database to use the sqitch defaults for Postgresql:

update_db:
        @echo "Running database migrations"
        @env PGHOST=$(DB_HOST) PGPORT=$(DB_PORT) PGPASSWORD=$(POSTGRES_PASSWORD) \
         PGUSER=$(POSTGRES_USER) PGDATABASE=$(POSTGRES_DB) sqitch deploy

Why not use the defaults in the docker compose file? Because I'm trying to think ahead and make sure my setup is future proof should I need to add more database models.

I was very pleased with this change since I always found the task of rebuilding the configuration file every time to have the properly environment variables to be an ugly hack.

I also cleaned up the Dockerfile for the application service:

FROM perl:5.38.0
WORKDIR /app

# Core OS setup
RUN apt-get update
RUN apt-get install -y postgresql-client git vim

# Clean up
RUN apt-get clean
RUN rm -rf /var/lib/apt/lists/*

# Copy only the files needed for installing dependencies
COPY cpanfile* .
RUN cpanm --notest --installdeps .

# Copy the rest of the application source code
COPY . .

# Run the Catalyst application
CMD make server 

I made similar changes to the Postgresql dockerfile. And I fixes a few minor bugs that popped up in testing. One was due to over enthusiastic copy pasta and I actually found a bug in the Valiant validations system which required a patch; that found it way to CPAN last night.

Thanks for the feedback everyone!