Unable to build PHP containers since the introduction of MSMTP in #19

[Molkobain]

Symptom

When trying to build PHP containers I get the following error:

 => ERROR [stage-0  9/10] COPY ../conf/msmtprc/msmtprc /var/www/.msmtprc         0.0s 
------                                                                                
 > [stage-0  9/10] COPY ../conf/msmtprc/msmtprc /var/www/.msmtprc:
------
php:33

--------------------

  31 |         && rm -rf /var/lib/apt/lists/*

  32 |     

  33 | >>> COPY ../conf/msmtprc/msmtprc /var/www/.msmtprc

  34 |     RUN chown www-data:www-data /var/www/.msmtprc \

  35 |     && chmod 600 /var/www/.msmtprc

--------------------

failed to solve: failed to compute cache key: failed to calculate checksum of ref wpjix3ouilcrtk5nlc0bs3gz7::aq9d2423g532j79o9s5df5lcg: "/conf/msmtprc/msmtprc": not found

Reproduction

• Get latest available version
• Force rebuild of PHP containers (e.g. docker-composer down php84 && docker-compose --env-file .env.local build php84 && docker-compose --env-file .env.local up -d php84)
• See the error occuring

Cause

In the docker compose file, PHP containers are build with a specific build context:

x-php-build: &default-php-build
  dockerfile: php
  context: ./build
  args:
    <<: *default-php-build-args

But the php DockerFile tries to copy a file from outside the build context which is forbidden:

COPY ../conf/msmtprc/msmtprc /var/www/.msmtprc

Note: Mind that Docker reworks the path to be absolute within the build context: "/conf/msmtprc/msmtprc": not found

So this can't work.

Proposed solutions

Quick fix

Replace the MSMTP configuration file in the php DockerFile so it points to the build/default_configuration folder. It would allow people to update their environment as it is presently broken.

The obvious drawback of this solution, is that the configuration won't be overridable by the user.

Replace

COPY ../conf/msmtprc/msmtprc /var/www/.msmtprc

With

COPY default_configuration/msmtprc/msmtprc /var/www/.msmtprc

Prettier solutions?

From what I understand, we don't use the root folder as the build context to avoid passing the whole ./html folder to the Docker builder daemon, which makes sense.

Maybe we should consider moving the conf within the /build folder alongside /build/default_configuration and rename it to something like /build/user_configuration?

Or maybe we should set it through a volume like we do for PHP *.ini files?

  volumes:
    - ${CONF_FOLDER}/php/php.ini:/usr/local/etc/php/conf.d/php.ini
    - ${CONF_FOLDER}/php/xdebug.ini:/usr/local/etc/php/conf.d/xdebug.ini
    ...

[Molkobain]

On second thoughts, I tried the approach that seems to both pretty and fixing the issue, so I made the PR #21 .
But it doesn't mean that we have to include it, if it's not the best solution.

[steffunky]

Good catch, I wasn't familiar with docker specific build context.
There's an issue as msmtprc still need a 600 file permissions and I'm not sure git can carry these permissions.

It works for now so I'll merge your PR but I'd rather have the conf folder available at build level, but that would require a substantial amount of change for a small fix

[Molkobain]

Discussed with @bdalsass and @steffunky , we leave the issue open even though #21 has been merged as the ideal solution might be to change where the user configuration is located so we can use them within the build context.