How to set custom environment variable on client building with docker

[marcosgcd]

Trying to add a custom environment variable in the Frontend that renders the build date REACT_APP_DATE (example).

I am using DOCKER_BUILDKIT=1 docker build -f deploy/docker/Dockerfile -t lowcoderorg/lowcoder-ce . to build.

I tried everything I could think of.

• created .env file in client/packages/lowcoder/.env
• added "build": "REACT_APP_DATE=2023-07-10 vite build && cp ../../VERSION ./build/VERSION" to client/packages/lowcoder/package.json
• Also Add REACT_APP_DATE to docker-compose.yaml and docker-compose-multi.yaml
• or ARG REACT_APP_DATE="2023-07-10" before build in Dockerfile

After build I still get undefined when trying to read it process.env.REACT_APP_DATE.
What am I doing wrong?

[FalkWolsky]

The disappointing answer is, that this is in general not possible this way.
Reason is, that Lowcoder Frontend is an app, that get's packed (build) before we dockerize it.
As such, only if you would change the source code and then build your own docker, you could make use of an ENV - but also only static. Unfortunately ENVs are not the way to inject dynamic values in the Frontend.