Related

Product App Platform: Run Docker containers without managing servers Product
How do you deploy a docker file to the App Platform? Question Question
Problems with Image caching Question Question

Question

How to use App Platform's bindable environment variables in Dockerfile

Posted November 4, 2020 474 views
DockerDigitalOcean App Platform

I was following the tutorial on How to Use Environment Variables in App Platform, and I am unable to figure out how to use these convenience variables in my Dockerfile.

I am specifically trying to print the COMMIT_HASH to a file in the container of my web component.

ARG web.COMMIT_HASH=unspecified
RUN echo ${web.COMMIT_HASH} > /www/commithash.txt

I’ve also tried pulling it in using ENV but that fails during build.

ENV GITHASH=${web\.COMMIT_HASH:-unspecified}
RUN echo ${GITHASH} > /www/githash.txt

It errors out at the . dot.

So is there a way to get these convenience environment variables into my Dockerfile?

Any help is greatly appreciated.

Add a comment
echoTHIS
By:
echoTHIS

Related

Product App Platform: Run Docker containers without managing servers Product
How do you deploy a docker file to the App Platform? Question Question
Problems with Image caching Question Question

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

×
1 answer
crashoverride November 4, 2020

👋 @echoTHIS

Great question, bindable variables are a template system for environment variables, not environment variables themselves.

You could create a environment variable called GITHASH with a value of ${web.COMMIT_HASH} in the DO App Platform UI. When we build or deploy your app we will inject an environment variable of $GITHASH with your commit hash.

Reply Report
  • echoTHIS November 4, 2020

    Excellent! That totally worked, thank you.

    In my app specification YAML file:

      envs:
  - key: GITHASH
    value: ${web.COMMIT_HASH}
    type: GENERAL

    And in my Dockerfile:

    ARG GITHASH=unspecified
RUN echo ${GITHASH} > /www/githash.txt

    One doctyl update later and I’m all set.

    Also I can’t believe I got an answer from @crashoverride I must say I’m a HUGE fan! Thank you for your help. Hack the planet!

    Reply Report
Submit an Answer

Related

Looking for something else?

Ask a new question Search for more help