add runtime env for production enironment

package-lock.json

@@ -1225,6 +1225,11 @@
         "@types/yargs": "^13.0.0"
       }
     },
+    "@mars/heroku-js-runtime-env": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/@mars/heroku-js-runtime-env/-/heroku-js-runtime-env-3.0.2.tgz",
+      "integrity": "sha1-5bhIDtgrVARkdKCKE5uNlWCvOig="
+    },
     "@mrmlnc/readdir-enhanced": {
       "version": "2.2.1",
       "resolved": "https://registry.npmjs.org/@mrmlnc/readdir-enhanced/-/readdir-enhanced-2.2.1.tgz",

package.json

@@ -3,6 +3,7 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
+    "@mars/heroku-js-runtime-env": "^3.0.2",
     "@testing-library/user-event": "^7.1.2",
     "flow-bin": "^0.114.0",
     "node-sass": "^4.13.0",
@@ -18,10 +19,8 @@
     "test": "react-scripts test",
     "eject": "react-scripts eject",
     "flow": "./node_modules/.bin/flow flow",
-
     "predeploy": "REACT_APP_ENVIRONMENT=production npm run build",
     "postinstall": "react-scripts build"
-
   },
   "eslintConfig": {
     "extends": "react-app"

src/config.js

@@ -1,3 +1,6 @@
+import runtimeEnv from '@mars/heroku-js-runtime-env';
+const env = runtimeEnv();
+
 const production = {
   apiAddress: 'https://node-go-api.herokuapp.com',
   endpoint: 'https://play-node-go.herokuapp.com'
@@ -8,7 +11,7 @@ const development = {
   endpoint: 'http://localhost:3000'
 }
 
-const config = process.env.REACT_APP_ENVIRONMENT === 'production' 
+const config = env.REACT_APP_ENVIRONMENT === 'production' 
   ? production
   : development