expo: expo SDK 49 does not load custom env file

Minimal reproducible example

https://github.com/dooboolab-community/expo-router-starter/pull/5

Summary

In expo SDK 48, it was possible to load custom .env file with dotenv -e .env.prod -- expo start. However, from SDK 49, it does not work.

You may try working example in https://github.com/dooboolab-community/expo-router-starter main branch and not working example in https://github.com/dooboolab-community/expo-router-starter/pull/5.

I setup .env and .env.prod with below variables. For .env,

ROOT_URL=localhost:3000

For .env.prod

ROOT_URL=localhost:5050

SDK 48 results

yarn start
yarn start:prod

SDK 49 results

yarn start
yarn start:prod

Environment

expo-env-info 1.0.5 environment info:
  System:
    OS: macOS 13.4.1
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 18.15.0 - ~/.nvm/versions/node/v18.15.0/bin/node
    Yarn: 3.6.0 - ~/.nvm/versions/node/v18.15.0/bin/yarn
    npm: 9.7.2 - ~/.nvm/versions/node/v18.15.0/bin/npm
    Watchman: 2023.07.10.00 - /opt/homebrew/bin/watchman
  Managers:
    CocoaPods: 1.12.1 - /opt/homebrew/bin/pod
  SDKs:
    iOS SDK:
      Platforms: DriverKit 22.4, iOS 16.4, macOS 13.3, tvOS 16.4, watchOS 9.4
  IDEs:
    Android Studio: 2021.2 AI-212.5712.43.2112.8815526
    Xcode: 14.3.1/14E300c - /usr/bin/xcodebuild
  npmPackages:
    @expo/webpack-config: ^18.1.2 => 18.1.2 
    expo: ^49.0.5 => 49.0.5 
    react: 18.2.0 => 18.2.0 
    react-dom: 18.2.0 => 18.2.0 
    react-native: 0.72.3 => 0.72.3 
    react-native-web: ~0.19.7 => 0.19.7 
  npmGlobalPackages:
    eas-cli: 3.16.0
  Expo Workflow: managed

About this issue

Original URL
State: open
Created a year ago
Reactions: 1
Comments: 20 (7 by maintainers)

Commits related to this issue

chore: resolve custom .env in expo 49 https://github.com/expo/expo/issues/23727\#issuecomment-1651609858 — committed to dooboolab-community/expo-router-starter by hyochan a year ago
chore: resolve custom .env in expo 49 https://github.com/expo/expo/issues/23727\#issuecomment-1651609858 — committed to dooboolab-community/expo-router-starter by hyochan a year ago
chore: resolve custom .env in expo 49 https://github.com/expo/expo/issues/23727\#issuecomment-1651609858 — committed to dooboolab-community/expo-router-starter by hyochan a year ago

Most upvoted comments

Would be very practical to allow for custom env files if possible. In our case, we have a staging environment for which we’d like to have a .env.staging but make it behave as if the NODE_ENV was production and also a qa environment with .env.qa. In our previous app, we had to use a hacky setup like proposed above but I’d much rather have something working out of the box for supporting custom environments other than development, test and production. Definitely a very nice step in the good direction for the environment variables with SDK 49 though.

DavidAmyot on Sep 29, 2023

I get a weird result as well the env vars work on ios / android but on web they are undefined 🤔 is there a solution for this ?

nicolae536 on Jul 26, 2023

maybe totally unrelated but when I build expo run:ios --configuration Release it says the .env is loaded when first running command but they are undefined at run time. exact same command without --configuration Release works

edit:

After messing with .env some more it seems like it’s wayyy more trouble than it’s worth and I’m not convinced it’s actually stable. Seems to not work in some cases, makes things less type safe, behavior with eas update seems inconsistent. Also, when using CI it’s required to generate a .env file during the action which is a pain.

Maybe I’m just dumb, but all these problems can be easily solved by just hardcoding the environment variable values and switching based in the eas.json updates channel.

iway1 on Sep 13, 2023

If you call the files .env.development and .env.production it works out of the box now in SDK 49.

Expo will load the production one automatically when you set NODE_ENV=production before you start the server. If you still need to load custom ENV files (even in EAS), with custom naming, hit me up. It’s possible but some changes are needed.

hirbod on Jul 26, 2023