Why can't I access my environment variables at build time when building from a Dockerfile on App Platform?

If you are using a Dockerfile to deploy your app on App Platform, environment variables are only available at build time if you have set them using the --build-arg option in Docker before deploying the app.

For example, to access the variable EXAMPLE=your-value during build time, set it in the image using the docker CLI like this:

docker build --build-arg EXAMPLE=your-value

You cannot use this method to access bindable variables at build time. If you are supplying a Dockerfile, bindable variables are only available at runtime.

Related Topics

Why can't I route traffic to my app's dedicated egress IP address?

Dedicated egress IPs route egress (outbound) traffic from an app. To route ingress (inbound) traffic to an app, use one of App Platform’s public ingress IPs.

Why doesn't my app's wildcard subdomain work?

Add the root domain to the list of domains in the app’s settings along with the wildcard subdomain.

Why is my app not resolving .gov domains?

App Platform apps may be slow or unable to resolve .gov domains because the domain administrators have blocked DigitalOcean’s IP addresses. To fix this, you can contact the domain administrator or use a custom DNS resolver.