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Version: 0.1.0-alpha.3

Environment Variables

Set environment variables directly in your invkfile. These are available to your scripts during execution.

Basic Usage​

{
    name: "build"
    env: {
        vars: {
            NODE_ENV: "production"
            API_URL: "https://api.example.com"
            DEBUG: "false"
        }
    }
    implementations: [{
        script: """
            echo "Building for $NODE_ENV"
            echo "API: $API_URL"
            """
        runtimes: [{name: "native"}]
        platforms: [{name: "linux"}, {name: "macos"}]
    }]
}

Variable Syntax​

Variables are key-value string pairs:

vars: {
    // Simple values
    NAME: "value"
    
    // Numbers (still strings in shell)
    PORT: "3000"
    TIMEOUT: "30"
    
    // Boolean-like (strings "true"/"false")
    DEBUG: "true"
    VERBOSE: "false"
    
    // Paths
    CONFIG_PATH: "/etc/myapp/config.yaml"
    OUTPUT_DIR: "./dist"
    
    // URLs
    API_URL: "https://api.example.com"
}

All values are strings. The shell interprets them as needed.

Referencing Other Variables​

Reference system environment variables:

vars: {
    // Use system variable
    HOME_CONFIG: "${HOME}/.config/myapp"
    
    // With default value
    LOG_LEVEL: "${LOG_LEVEL:-info}"
    
    // Combine variables
    FULL_PATH: "${HOME}/projects/${PROJECT_NAME}"
}

Note: References are expanded at runtime, not definition time.

Scope Levels​

Root Level​

Available to all commands:

env: {
    vars: {
        PROJECT_NAME: "myproject"
        VERSION: "1.0.0"
    }
}

cmds: [
    {
        name: "build"
        // Gets PROJECT_NAME and VERSION
        implementations: [...]
    },
    {
        name: "deploy"
        // Also gets PROJECT_NAME and VERSION
        implementations: [...]
    }
]

Command Level​

Available to specific command:

{
    name: "build"
    env: {
        vars: {
            BUILD_MODE: "release"
        }
    }
    implementations: [...]
}

Implementation Level​

Available to specific implementation:

{
    name: "build"
    implementations: [
        {
            script: "npm run build"
            runtimes: [{name: "native"}]
            platforms: [{name: "linux"}, {name: "macos"}, {name: "windows"}]
            env: {
                vars: {
                    NODE_ENV: "production"
                }
            }
        },
        {
            script: "go build ./..."
            runtimes: [{name: "native"}]
            platforms: [{name: "linux"}, {name: "macos"}, {name: "windows"}]
            env: {
                vars: {
                    CGO_ENABLED: "0"
                }
            }
        }
    ]
}

Platform Level​

Per-platform variables:

// Platform-specific env requires separate implementations
implementations: [
    {
        script: "echo $PLATFORM_CONFIG"
        runtimes: [{name: "native"}]
        platforms: [{name: "linux"}]
        env: {
            vars: {
                PLATFORM_CONFIG: "/etc/myapp"
                PLATFORM_NAME: "Linux"
            }
        }
    },
    {
        script: "echo $PLATFORM_CONFIG"
        runtimes: [{name: "native"}]
        platforms: [{name: "macos"}]
        env: {
            vars: {
                PLATFORM_CONFIG: "/usr/local/etc/myapp"
                PLATFORM_NAME: "macOS"
            }
        }
    },
    {
        script: "echo %PLATFORM_CONFIG%"
        runtimes: [{name: "native"}]
        platforms: [{name: "windows"}]
        env: {
            vars: {
                PLATFORM_CONFIG: "%APPDATA%\\myapp"
                PLATFORM_NAME: "Windows"
            }
        }
    }
]

Combined with Files​

Variables override values from env files:

env: {
    files: [".env"]  // Loaded first
    vars: {
        // These override .env values
        OVERRIDE: "from-invkfile"
    }
}

CLI Override​

Override at runtime:

# Single variable
invowk cmd build --invk-env-var NODE_ENV=development

# Multiple variables
invowk cmd build --invk-env-var NODE_ENV=dev --invk-env-var DEBUG=true --invk-env-var PORT=8080

CLI variables have the highest priority.

Real-World Examples​

Build Configuration​

{
    name: "build"
    env: {
        vars: {
            NODE_ENV: "production"
            BUILD_TARGET: "es2020"
            SOURCEMAP: "false"
        }
    }
    implementations: [{
        script: "npm run build"
        runtimes: [{name: "native"}]
        platforms: [{name: "linux"}, {name: "macos"}, {name: "windows"}]
    }]
}

API Configuration​

{
    name: "start"
    env: {
        vars: {
            API_HOST: "0.0.0.0"
            API_PORT: "3000"
            API_PREFIX: "/api/v1"
            CORS_ORIGIN: "*"
        }
    }
    implementations: [{
        script: "go run ./cmd/server"
        runtimes: [{name: "native"}]
        platforms: [{name: "linux"}, {name: "macos"}, {name: "windows"}]
    }]
}

Dynamic Values​

{
    name: "release"
    env: {
        vars: {
            // Git-based version
            GIT_SHA: "$(git rev-parse --short HEAD)"
            GIT_BRANCH: "$(git branch --show-current)"
            
            // Timestamp
            BUILD_TIME: "$(date -u +%Y-%m-%dT%H:%M:%SZ)"
            
            // Combine values
            BUILD_ID: "${GIT_BRANCH}-${GIT_SHA}"
        }
    }
    implementations: [{
        script: """
            echo "Building $BUILD_ID at $BUILD_TIME"
            go build -ldflags="-X main.version=$BUILD_ID" ./...
            """
        runtimes: [{name: "native"}]
        platforms: [{name: "linux"}, {name: "macos"}]
    }]
}

Database Configuration​

{
    name: "db migrate"
    env: {
        vars: {
            DB_HOST: "${DB_HOST:-localhost}"
            DB_PORT: "${DB_PORT:-5432}"
            DB_NAME: "${DB_NAME:-myapp}"
            DB_USER: "${DB_USER:-postgres}"
            // Construct URL from parts
            DATABASE_URL: "postgres://${DB_USER}@${DB_HOST}:${DB_PORT}/${DB_NAME}"
        }
    }
    implementations: [{
        script: "migrate -database $DATABASE_URL up"
        runtimes: [{name: "native"}]
        platforms: [{name: "linux"}, {name: "macos"}]
    }]
}

Container Environment​

Variables are passed into containers:

{
    name: "build"
    env: {
        vars: {
            GOOS: "linux"
            GOARCH: "amd64"
            CGO_ENABLED: "0"
        }
    }
    implementations: [{
        script: "go build -o /workspace/bin/app ./..."
        runtimes: [{name: "container", image: "golang:1.21"}]
        platforms: [{name: "linux"}]
    }]
}

Best Practices​

  1. Use defaults: ${VAR:-default} for optional config
  2. Keep secrets out: Don't hardcode secrets; use env files or external secrets
  3. Document variables: Add comments explaining each variable
  4. Use consistent naming: UPPER_SNAKE_CASE convention
  5. Scope appropriately: Root for shared, command for specific

Next Steps​