How to override proxy settings via command line with Create React App?

Question

I set up a React project using Create React App. The development server is configured to proxy API requests via the proxy setting in my package.json:

...
  "proxy": "https://dev-backend.example.com"
...

Is there any possibility to override this settings via command line, environment variable or anything similar? I want to be able to change the proxy address in local development without editing the package.json, because that often leads to accidentally checking in the wrong proxy address into SCM.

What I want to do is something like this to start a development server that proxies to another backend:

$ PROXY=http://localhost:8080 npm start

This GitHub issue is about the same topic, but doesn't propose an easy solution to achieve the desired functionality.

user_5079741 · Answer

I searched for an answer to this question as well and found a solution that worked for me.

In short, I used the approach proposed in the official docs: https://create-react-app.dev/docs/proxying-api-requests-in-development/#configuring-the-proxy-manually

Since I also wanted to set it via an environment variable but didn't find this exact solution anywhere, I posted my own answer here: set proxy in package.json to env variable

How to override proxy settings via command line with Create React App?

1 Answers