What strategy is used to pass env vars during image build?

[Kwadz]

First of all, thank you for this amazing PHP dockerisation! 👏

I noticed that the env vars are used to create ini files from templates. However I didn't see any ARG and ENV values in Dockefile, for example for PHP_XDEBUG_REMOTE_HOST used in docker-php-ext-xdebug.ini.tmpl#L38.

How come you're able to get this env vars available in Dockerfile (when executing docker-entrypoint.sh), without using ARG and ENV?

[Kwadz]

For example, if I add RUN printenv just before ENTRYPOINT ["/docker-entrypoint.sh"] in Dockerfile, I can read all the env vars that are passed via ENV in Dockerfile but I can't see PHP_XDEBUG_REMOTE_HOST while you've been able to use it just after in docker-entrypoint.sh.

How did you make it possible?

[weitzman]

In Drush’s implementation, the env vars are brought into the container via docker-compose.yml

[Kwadz]

Yes, it's exactly what I do and wodby does. The thing is you won't have this vars present during the image creation, as I mentioned:

I can read all the env vars that are passed via ENV in Dockerfile but I can't see PHP_XDEBUG_REMOTE_HOST

I have it visible with printenv only after a first restart of the container.

My docker-compose.yml:

version: "3"

services:
  php:
    build:
      context: .
    environment:
      PHP_SENDMAIL_PATH: /usr/sbin/sendmail -t -i -S mailhog:1025
      DB_HOST: $DB_HOST
      DB_USER: $DB_USER
      DB_PASSWORD: $DB_PASSWORD
      DB_NAME: $DB_NAME
      PHP_FPM_USER: wodby
      PHP_FPM_GROUP: wodby
# Read instructions at https://wodby.com/docs/stacks/php/local/#xdebug
      PHP_XDEBUG: 1
      PHP_XDEBUG_DEFAULT_ENABLE: 1
      PHP_XDEBUG_REMOTE_CONNECT_BACK: 0
      PHP_IDE_CONFIG: serverName=my-ide
      PHP_XDEBUG_IDEKEY: "my-ide"
      PHP_XDEBUG_REMOTE_HOST: 10.254.254.254 # macOS
    volumes:
      - ./:/var/www/html

So, I'm wondering how it is possible that wodby use them during image creation in docker-entrypoint.sh for config files generation from templates.

[andypost]

Looks you're expecting this env vars at image build time but they are for container start only

[Kwadz]

Good catch @andypost! I had in my Dockerfile:

RUN ["/docker-entrypoint.sh"]

while wodby uses:

ENTRYPOINT ["/docker-entrypoint.sh"]

The first is executed during image build while the second at the container start.