hughack / json-simple-template

JSON Template Populator Action

A GitHub Action that populates JSON templates with configuration values. Ideal for setting up distinct environments, such as development and production, for cloud-hosted applications.

How It Works

• Define a JSON template with placeholders marked as $variableName for single value replacements, or use backtick strings with ${variableName} for in-string replacements.
• Supply a configuration JSON file containing values for these placeholders.
• The action will output a new JSON file with all placeholders replaced by the corresponding values from the configuration.

Usage

Include the action in your workflow configuration:

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2

    - name: Populate JSON Template
      uses: hughack/json-simple-template@v0.2.0
      with:
        config-file: 'path/to/config.json'
        template-file: 'path/to/template.json'
        output-file: 'path/to/output.json'

Environment-Based Examples

Assuming a web application needs different configurations for its development and production cloud environments.

Template File (template.json):

{
  "databaseEndpoint": $dbEndpoint,
  "assetsDomain": `https://${assetDomain}`,
  "loggingLevel": $logLevel,
  "cache": {
    "type": $cacheType,
    "duration": $cacheDuration
  }
}

Development Config (dev-config.json):

{
  "dbEndpoint": "https://dev-db.mysite.cloud",
  "assetDomain": "dev-assets.mysite.cloud",
  "logLevel": "verbose",
  "cacheType": "memory",
  "cacheDuration": 3600
}

Production Config (prod-config.json):

{
  "dbEndpoint": "https://db.mysite.cloud",
  "assetDomain": "assets.mysite.cloud",
  "logLevel": "error",
  "cacheType": "redis",
  "cacheDuration": 86400
}

Output for Development:

{
  "databaseEndpoint": "https://dev-db.mysite.cloud",
  "assetsDomain": "https://dev-assets.mysite.cloud",
  "loggingLevel": "verbose",
  "cache": {
    "type": "memory",
    "duration": 3600
  }
}

Output for Production:

{
  "databaseEndpoint": "https://db.mysite.cloud",
  "assetsDomain": "https://assets.mysite.cloud",
  "loggingLevel": "error",
  "cache": {
    "type": "redis",
    "duration": 86400
  }
}