React Native - Build config access from JS (android only for now)

Module to expose build config variables set in Gradle to your javascript code in React Native.

Inspired from deprecated luggit/react-native-build-config.

Install

npm i ismaeldcom/react-native-build-config

RN > 0.47 use 0.11 or higher

Automatically link

With React Native 0.27+

react-native link react-native-build-config

With older versions of React Native

You need rnpm (npm install -g rnpm)

rnpm link react-native-device-info

Manually link

1. Include this module in android/settings.gradle:

include ':react-native-build-config'
include ':app'

project(':react-native-build-config').projectDir = new File(rootProject.projectDir,
  '../node_modules/react-native-build-config/android')

2. Add a dependency to your app build in android/app/build.gradle:

dependencies {
    ...
    compile project(':react-native-build-config')
}

3. Change your main activity to add a new package, in android/app/src/main/.../MainActivity.java:

import com.ismaeld.RNBuildConfig.RNBuildConfigPackage; // add import

public class MainApplication extends Application implements ReactApplication {

  private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {

      /* ... */

      @Override
      protected List<ReactPackage> getPackages() {
          return Arrays.<ReactPackage>asList(
                  new MainReactPackage(),
                  new RNBuildConfigPackage(BuildConfig.class), // add the package here
          );
      }
  };

Usage

Declare config variables in Gradle, under android/app/build.gradle:

android {
    defaultConfig {
        buildConfigField "String",  "API_URL",     '"https://myapi.com"'
        buildConfigField "Boolean", "SHOW_ERRORS", "true"
        ...

Then access those from javascript:

const BuildConfig = require('react-native-build-config');

BuildConfig.API_URL     // "https://myapi.com"
BuildConfig.SHOW_ERRORS // true

Gradle sets some variables by default:

• VERSION_NAME and VERSION_CODE, both coming from the build settings. Keep in mind the code is a number
• APPLICATION_ID: Your package name, eg: com.Example
• DEBUG: set to true when running the app locally
• BUILD_TYPE and FLAVOR: more build settings