feat(config): support env var config via dotenv

Allow Form to be configured using a .env file, read by dotenv and
populated into `process.env`.

- `npm install dotenv`
- pick up the `.env` config using dotenv just before we invoke
  the application
- remove `.env` entry from `.dockerignore`

.dockerignore

@@ -5,7 +5,6 @@
 **/.elasticbeanstalk
 **/node_modules
 **/public/lib
-**/.env
 .eslintrc.json
 .prettierrc.json
 .travis.yml

README.md

@@ -91,9 +91,6 @@ FormSG requires some environment variables in order to function.
 More information about the required environment variables can be seen in
 [DEPLOYMENT_SETUP.md](/docs/DEPLOYMENT_SETUP.md).
 
-The docker-compose file declares some blank environment variables that are secret and cannot be committed into
-the repository. See below instructions to get them injected into the container.
-
 We provide a [`.template-env`](./.template-env) file with the secrets blanked out. You can copy and
 paste the variables described into a self-created `.env` file, replacing the
 required values with your own.

package.json

@@ -24,9 +24,9 @@
     "build-frontend": "webpack --config webpack.prod.js",
     "build-frontend-dev": "webpack --config webpack.dev.js",
     "build-frontend-dev:watch": "webpack --config webpack.dev.js --watch",
-    "start": "node dist/backend/app/server.js",
+    "start": "node -r dotenv/config dist/backend/app/server.js",
     "dev": "docker-compose up --build",
-    "docker-dev": "npm run build-frontend-dev:watch & ts-node-dev --respawn --transpile-only --inspect=0.0.0.0 --exit-child -- src/app/server.ts",
+    "docker-dev": "npm run build-frontend-dev:watch & ts-node-dev --respawn --transpile-only --inspect=0.0.0.0 --exit-child -r dotenv/config -- src/app/server.ts",
     "test": "npm run test-backend && npm run test-frontend",
     "download-binary": "node tests/end-to-end/helpers/get-mongo-binary.js",
     "test-e2e": "npm run test-e2e-build && npm run test-e2e-ci",
@@ -99,6 +99,7 @@
     "csv-string": "^4.0.1",
     "date-fns": "^2.22.1",
     "dedent-js": "~1.0.1",
+    "dotenv": "^10.0.0",
     "ejs": "^3.1.6",
     "express": "^4.16.4",
     "express-device": "~0.4.2",
@@ -253,4 +254,4 @@
     "webpack-merge": "^4.1.3",
     "worker-loader": "^2.0.0"
   }
-}
+}