Environment variables

Learn how to use environment variables with Serverless and AWS Lambda. These allow you to store things like database connection settings and API keys. Environment variables can be shared across multiple functions or you can limit them to specific functions only.

Global

The first way of defining environment variables is by adding them to the provider section of the serverless.yml config file.

provider:
  name: aws
  runtime: nodejs6.10
  stage: dev
  region: eu-west-1
  profile: savjeebe-demo

  # Available to ALL functions in your service.
  environment:
    GOOGLE_MAPS_API_KEY: key1234

All variabels that are defined here will be available to all the functions in your project (service).

Scoped to function

The second way is by adding them to a specific function:

functions:
  myFunctionName:
    handler: fileName.handler
    events:
      - http:
          path: myfunction
          method: GET
    environment:
      OTHER_API_KEY: key56789

Environment variables defined here will only be available to this function. You can also overwrite global environment variables that you defined in the provider section.

Using them in node.js

After defining the environment variables you can use them in your Lambda functions. Each of your variables is added to the process.env object and can be accessed like this:

module.exports.handler = (event, context, callback) => {

  // It has access to global env variables
  console.log(process.env.GOOGLE_MAPS_API_KEY);

  // And also to local scoped variables
  console.log(process.env.OTHER_API_KEY);

  // Some business logic here
  // & calling the callback function
}

Environment variables

Global

Scoped to function

Using them in node.js

Useful resources