wooodhead/serverless-dotenv-plugin

Preload Environment Variables with Dotenv into Serverless

serverless-dotenv-plugin

Preload environment variables into serverless. Use this plugin if you have variables stored in a .env file that you want loaded into your serverless yaml config. This will allow you to reference them as ${env:VAR_NAME} inside your config and it will load them into your lambdas.

Install and Setup

First, install the plugin:

> npm i -D serverless-dotenv-plugin

Next, add the plugin to your serverless config file:

service: myService
plugins:
  - serverless-dotenv-plugin
...

Now, just like you would using dotenv in any other JS application, create your .env file in the root of your app:

DYNAMODB_TABLE=myTable
AWS_REGION=us-west-1
AUTH0_CLIENT_ID=abc12345
AUTH0_CLIENT_SECRET=12345xyz

Automatic ENV File Resolution (as of verson 3.0+ Thanks to @danilofuchs!)

By default, the plugin looks for the file: .env. In most use cases this is all that is needed. However, there are times where you want different env files based on environment. For instance:

.env.development
.env.production

When you deploy with NODE_ENV set: NODE_ENV=production sls deploy the plugin will look for files named .env, .env.production, .env.production.local. If for some reason you can't set NODE_ENV, you could always just pass it in as an option: sls deploy --env production or sls deploy --stage production. If NODE_ENV, --env or --stage is not set, it will default to development.

The precedence between the options is the following: NODE_ENV > --env > --stage

The env resolution pattern follows the one used by Rail's dotenv and create-react-app

Valid .env file names	Description
.env	Default file, always included
.env.local	Included in all environments except test
.env.development	If NODE_ENV or --env or --stage is not set, will try to load .env.development.
.env.{ENV}	If NODE_ENV or --env or --stage is set, will try to load .env.{env}.
.env.{ENV}.local	Every env set up in .env.{ENV}.local will override other envs

Note: .env, .env.development, and .env.production files should be included in your repository as they define defaults. .env*.local should be added to .gitignore, as those files are intended to be ignored. .env.local is where secrets can be stored.

Plugin options

path: path/to/my/.env

The plugin will look for your .env file in the same folder where you run the command using the file resolution rules as described above, but these rules can be overridden by setting the path option. This will disable automatic env file resolution

basePath: path/to/my/

The problem with setting the path option is that you lose environment resolution on the file names. If you don't need environment resolution, the path option is just fine. If you do, then use the basePath option.

include: ...

All env vars found in your file will be injected into your lambda functions. If you do not want all of them to be injected into your lambda functions, you can whitelist them with the include option.

exclude: ...

(Added Feb 2, 2020 by @smcelhinney)

If you do not want all of them to be injected into your lambda functions, you can blacklist the unnecessary ones with the exclude option. Note, this is only available if the include option has not been set.

Example:

custom:
  dotenv:
    exclude:
      - NODE_ENV # E.g for Google Cloud Functions, you cannot pass this env variable.

logging: true|false (default true)

(Added Feb 2, 2020 by @kristopherchun)

By default, there's quite a bit that this plugin logs to the console. You can now quiet this with the new logging option. (This defaults to true since this was the original behavior)

Complete example:

custom:
  dotenv:
    path: path/to/my/.env (default ./.env)
    basePath: path/to/ (default ./)
    logging: false
    include:
      - AUTH0_CLIENT_ID
      - AUTH0_CLIENT_SECRET

required.file: true|false (default false)

By default, this plugin will exit gracefully and allow Serverless to continue even if it couldn't find a .env file to use. Set this to true to cause Serverless to halt if it could not find a .env file to use.

Complete example:

custom:
  dotenv:
    required:
      file: true

Usage

Once loaded, you can now access the vars using the standard method for accessing ENV vars in serverless:

...
provider:
  name: aws
  runtime: nodejs6.10
  stage: ${env:STAGE}
  region: ${env:AWS_REGION}
...

Lambda Environment Variables

Again, remember that when you deploy your service, the plugin will inject these environment vars into any lambda functions you have and will therefore allow you to reference them as process.env.AUTH0_CLIENT_ID (Nodejs example).

Examples

You can find example usage in the examples folder.

Changelog

https://colyn.dev/serverless-dotenv-plugin-changelog/

Contributing

Because of the highly dependent nature of this plugin (i.e. thousands of developers depend on this to deploy their apps to production) I cannot introduce changes that are backwards incompatible. Any feature requests must first consider this as a blocker. If submitting a PR ensure that the change is developer opt-in only meaning it must guarantee that it will not affect existing workflows, it's only available with an opt-in setting. I appreciate your patience on this. Thanks.

Contributors

This project exists thanks to all the people who contribute.