Correct .env file with serverless-dotenv-plugin

Question

I'm using the following as a custom serverless-dotenv-plugin plugin configuration:

custom: dotenv: path: .env-${opt:stage, 'local'}

But what I'm really trying to get is that the environment be loaded from .env file when I give no arguments and .env.staging file when I use staging as a CLI argument.

I don't know how this can be reflected in path above. Any help please?

Answer 1

I got your use case to work by just using the normal dotenv plugin.

In my serverless.yaml, I specify environment variables to be loaded from a file based on the stage parameter (dev is default):

provider: 
  stage: ${opt:stage, 'dev'}
  environment:
    FOO: ${file(./config.${self:provider.stage}.js):getEnvVars.FOO}
    BAR: ${file(./config.${self:provider.stage}.js):getEnvVars.BAR}

---

Then one file per stage that loads the environment variables from the right .env file:

config.dev.js:

require('dotenv').config({path: __dirname + '/dev.env'});
const config = require('./environmentVariables.js');
module.exports.getEnvVars = config.getEnvVars;

config.production.js:

require('dotenv').config({path: __dirname + '/production.env'});
const config = require('./environmentVariables.js');
module.exports.getEnvVars = config.getEnvVars;

---

Instead of exporting every environment variables in each of the above config files, I created a helper file for this (environmentVariables.js):

module.exports.getEnvVars = () => ({
    FOO: process.env.FOO,
    BAR: process.env.BAR
});

---

Last but not least the .env files containing the actual variables. I named the files dev.env and production.env.

FOO=foo
BAR=bar

---

It works like a charm, the only downside being that you have to edit several different files whenever you want to add a new environment variable.