Serverless YAML extension parser

This tiny library will parse YAML extensions used in serverless framework.

Usage

npm install sls-yaml

import yaml from "sls-yaml";
const compiledYamlAsJsonObject = yaml(YAML_FILE_PATH_OR_BUFFER);

Supported sls extensions

• Include external file ${file(path/to/file.yml)}
• Inject environment variable ${env:NODE_ENV}
• Inject global variables ${global:path.to.variable}
• Inject local variables ${self:path.to.variable}

New extensions*

• Inject current git branch ${git:branch}
• Inject last git commit hash ${git:sha1}
• String replace ${replace(str, searchPattern, replaceValue )}

* - New extension not present in serverless yaml

Custom extensions

const context = {
  custom: ([arg]: string[]) => {
    return `${arg}-beta`;
  }
};
const result = yaml(content, null, context);

name: service
version: v1.0.2
subset: service@${custom(${self:version})}

• output

name: service
version: v1.0.2
subset: [email protected]

Include external file

This extension will include content of external yaml files.

• config.yml

version: 1
env: dev
config: ${file(./common.yml)}

• common.yml

endpoint: http://service-url

• Generated final yaml

version: 1
env: dev
config:
  endpoint: http://service-url

Inject environment variable

This extension will inject envronment values

• config.yml export NODE_ENV = development

version: 1
env: ${env:NODE_ENV}

• Generated final yaml

version: 1
env: development

Inject global variables

This extension will inject variable from global scope.

• config.yml

version: 1
env: stage
config: ${file(./common.yml)}

• common.yml

endpoint: http://service-${global:env}

• Generated final yaml

version: 1
env: stage
config:
  endpoint: http://service-stage

Inject local variables

This extension will inject variable from local scope.

• config.yml

version: 1
env: stage
config: ${file(./common.yml)}

• common.yml

port: 8080
endpoint: http://service:${self:port}

• Generated final yaml

version: 1
env: stage
config:
  port: 8080
  endpoint: http://service:8080

Inject current git branch

This extension will inject current git branch name

• config.yml

branch: ${git:branch}

Inject last git commit hash

This extension will inject last git commit hash

• config.yml

image.tag: ${git:sha1}

String replace

replace(str:string, searchPattern:RegExp|string, replaceValue:string )

This extension will returns a new string with some or all matches of a pattern replaced by a replacement. The pattern can be a string or a RegExp, and the replacement can be a string or a function to be called for each match. If pattern is a string, only the first occurrence will be replaced.

• config.yml

version: v1.0.0
name: ServiceName@${replace(${ self : version }, /\\./gi, - )}

• output

version: v1.0.0
name: ServiceName@v1-0-0