Environment Variables

Environment variables configuration source, included in the core package.

Default Level

The default level for this configuration source is CfgSourceLevels.EnvironmentVariables (400).

If you don't specify the level parameter, the default level will be used:

// Uses default level 400
.AddEnvironmentVariables(prefix: "APP_")

// Specify custom level
.AddEnvironmentVariables(prefix: "APP_", level: 450)

Basic Usage

using Apq.Cfg;

var cfg = new CfgBuilder()
    .AddEnvironmentVariables(prefix: "APP_")  // Uses default level 400
    .Build();

Prefix Filtering

Use prefix to filter relevant variables:

# These will be included with prefix "APP_"
APP_NAME=MyApp
APP_PORT=8080
APP_DATABASE__HOST=localhost

# These will be excluded
OTHER_VAR=value

Key Mapping

Environment variables use double underscore for hierarchy:

Environment Variable	Configuration Key
APP_NAME	Name
APP_DATABASE__HOST	Database:Host
APP_DATABASE__PORT	Database:Port

Priority

Environment variables have the highest default priority (level 400) to allow runtime overrides.

Next Steps

• JSON - File-based configuration
• Config Merge - How merging works