Setup appsettings template for different environments in repository

[zhifenglee-aelf]

User Story
As a developer, I want to set up environment-specific appsettings templates in our repository so that configuration can be easily managed and maintained across Development, Staging, and Production environments.

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Details & Requirements

1. Template Structure

   • Base Configuration:
     • Create a base appsettings.json that contains common configuration settings applicable to all environments.
   • Environment-Specific Overrides:
     • Create additional configuration files for each environment (e.g., appsettings.Development.json, appsettings.Staging.json, appsettings.Production.json).
     • Ensure that environment-specific files override the base configuration as needed.
   • Sensitive Data Handling:
     • Use placeholders or external secrets management for sensitive settings like API keys and connection strings.

2. Configuration Loading

   • Configure the application to load appsettings.json first and then override settings with the environment-specific file based on the current environment variable (e.g., ASPNETCORE_ENVIRONMENT).
   • Validate that the configuration system properly merges the files.

3. Version Control & Documentation

   • Include all appsettings templates in the repository to provide a starting point for all developers.
   • Document the purpose of each configuration file and how to modify them for local development or deployment.
   • Provide instructions on how to integrate with a secrets manager if applicable.

4. Testing & Validation

   • Write tests or include manual test procedures to confirm that the correct settings are loaded for each environment.
   • Validate that changes in environment-specific files properly override base settings.

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Acceptance Criteria

• The repository includes a appsettings.json and separate environment-specific files such as appsettings.Development.json, appsettings.Staging.json, and appsettings.Production.json.
• The application correctly loads and merges configuration settings based on the ASPNETCORE_ENVIRONMENT variable.
• Documentation is available, detailing how to use and customize the configuration templates.
• Sensitive data is managed securely, using placeholders or integrated secrets management.

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Implementation Notes / Tasks

• File Creation:
  • Add a base appsettings.json to the repository with default values.
  • Create additional files for each environment:
    • appsettings.Development.json
    • appsettings.Staging.json
    • appsettings.Production.json
• Configuration Setup:
  • Update the application's startup configuration (e.g., in .NET, modify the CreateDefaultBuilder in Program.cs) to load the environment-specific configuration files.
• Documentation:
  • Update the repository README or create a dedicated CONFIGURATION.md file to explain the configuration files and environment override process.
• Testing:
  • Manually verify configuration loading by switching the environment variable.
  • Optionally, implement unit tests to assert that key configuration values are correctly applied for each environment.

By following these steps, the repository will have a robust and flexible configuration management setup that supports different environments effectively.