Serverless Parent Plugin

Share common configuration between services

Requirements:

• Serverless v1.12.x or higher.
• AWS provider

How it works

Serverless Plugin that allows you to keep common configuration in a parent serverless.yml

Setup

Install via npm in the root of your Serverless service:

npm install serverless-plugin-parent --save-dev

• Add the plugin to the plugins array in your Serverless serverless.yml:

plugins:
  - serverless-plugin-parent

Default Usage - Discover Serverless.yml

The plugin will recursively search all parent directories for a serverless.yml file until it reaches the user's home direcory or has gone x number of directories up. The default value is 3 but this can be configured using

custom:
  parent:
    maxLevels: 2     # Optional (Default 3)

Per default the parent file will overwrite settings in the service files. If you want the service file to have a higher priority you can change that using

custom:
  parent:
    overwriteServiceConfig: false     # Optional (Default true)

Project Structure

<project_root>
- service1
  - hello.js
  - serverless.yml
- service2
  - goodbye.js
  - serverless.yml
- serverless.yml

serverless.yml

provider:
  name: aws
  stage: ${opt:stage, "Test"}
  runtime: nodejs8.10
  role: DefaultRole

resources:
  Resources:
    DefaultRole:
      Type: AWS::IAM::Role
      Properties:
        Path: /
        RoleName: ${self:service}-${self:provider.stage}
        AssumeRolePolicyDocument:
          Version: "2012-10-17"
          Statement:
            - Effect: Allow
              Principal:
                Service:
                  - lambda.amazonaws.com
              Action: sts:AssumeRole
        Policies:
          - PolicyName: ${self:service}-${self:provider.stage}
            PolicyDocument:
              Version: "2012-10-17"
              Statement:
                - Effect: Allow
                  Action:
                    - logs:CreateLogGroup
                    - logs:CreateLogStream
                    - logs:PutLogEvents
                  Resource: arn:aws:logs:${self:provider.region}:*:log-group:/aws/lambda/*:*:*

service1/serverless.yml

service: Service1

plugins:
  - serverless-plugin-parent

provider:
  environment:
    HELLO_MESSAGE: Mholo

functions:
  Hello:
    handler: hello.handle
    events:
      - http:
          path: hello
          method: get
          cors: true

Effective serverless.yml

service: Service1

provider:
  name: aws
  stage: ${opt:stage, "Test"}
  runtime: nodejs8.10
  role: DefaultRole

plugins:
  - serverless-plugin-parent

provider:
  environment:
    HELLO_MESSAGE: Mholo

functions:
  Hello:
    handler: hello.handle
    events:
      - http:
          path: hello
          method: get
          cors: true

resources:
  Resources:
    DefaultRole:
      Type: AWS::IAM::Role
      Properties:
        Path: /
        RoleName: ${self:service}-${self:provider.stage}
        AssumeRolePolicyDocument:
          Version: "2012-10-17"
          Statement:
            - Effect: Allow
              Principal:
                Service:
                  - lambda.amazonaws.com
              Action: sts:AssumeRole
        Policies:
          - PolicyName: ${self:service}-${self:provider.stage}
            PolicyDocument:
              Version: "2012-10-17"
              Statement:
                - Effect: Allow
                  Action:
                    - logs:CreateLogGroup
                    - logs:CreateLogStream
                    - logs:PutLogEvents
                  Resource: arn:aws:logs:${self:provider.region}:*:log-group:/aws/lambda/*:*:*

Alternate Usage - Defined parent configuration path

Project Structure

<project_root>
- parent
  - serverless.yml
- service1
  - hello.js
  - serverless.yml
- service2
  - goodbye.js
  - serverless.yml

service1/serverless.yml

custom:
  parent:
    path: ../parent
    # or 
    path: ../parent/serverless.yml

Contribute

Help us making this plugin better and future proof.

• Clone the code
• Install the dependencies with npm install
• Create a feature branch git checkout -b new_feature
• Lint with standard npm run lint

License

This software is released under the MIT license. See the license file for more details.