#+TITLE: Web Server Configuration Example #+PROPERTY: TAGS example webserver go-cfg #+AUTHOR: go-cfg Project #+OPTIONS: toc:2 num:t

• Overview

This example demonstrates configuring a basic HTTP web server using go-cfg. It showcases:

• Network configuration (host, port)
• TLS/HTTPS settings
• Timeout configuration
• Feature flags
• Configuration file loading
• Environment-specific settings

• Configuration Options

** Network Settings

• =host= - Server bind address (default: localhost)
• =port= - Server port (default: 8080)

** TLS Configuration

• =enable_tls= - Enable HTTPS (default: false)
• =tls_cert_file= - Path to TLS certificate file
• =tls_key_file= - Path to TLS private key file

** Timeouts

• =read_timeout= - HTTP read timeout (default: 30s)
• =write_timeout= - HTTP write timeout (default: 30s)
• =idle_timeout= - HTTP idle timeout (default: 120s)

** Feature Flags

• =enable_metrics= - Enable /metrics endpoint (default: true)
• =enable_logging= - Enable request logging (default: true)
• =enable_cors= - Enable CORS headers (default: false)

** Operational

• =environment= - Environment name (default: development)
• =debug= - Debug mode (default: false)
• =log_level= - Logging level (default: info)

• Running the Example

** Basic Usage

#+BEGIN_SRC bash

Run with defaults

go run main.go

View help and all options

go run main.go --help

Custom host and port

go run main.go --host=0.0.0.0 --port=9000 #+END_SRC

** Environment Variables

#+BEGIN_SRC bash

Set configuration via environment variables

export HOST=127.0.0.1 export PORT=8080 export ENVIRONMENT=production export DEBUG=false go run main.go #+END_SRC

** Configuration File

#+BEGIN_SRC bash

Use provided YAML configuration

go run main.go --config-file=server.yaml

Create custom configuration

go run main.go --config-file=my-config.json #+END_SRC

** TLS/HTTPS Mode

#+BEGIN_SRC bash

Enable TLS (requires certificate files)

go run main.go --enable-tls --tls-cert-file=cert.pem --tls-key-file=key.pem #+END_SRC

• Testing the Server

Once running, test the server endpoints:

#+BEGIN_SRC bash

Health check

curl http://localhost:8080/health

Main page

curl http://localhost:8080/

Metrics (if enabled)

curl http://localhost:8080/metrics #+END_SRC

• Configuration Priority

Configuration sources are applied in this order (later overrides earlier):

1. Default values (in struct tags)
2. Configuration file (if --config-file specified)
3. Environment variables (HOST, PORT, etc.)
4. Command-line flags (--host, --port, etc.)

• Example Configurations

** Development #+BEGIN_SRC yaml host: "localhost" port: 8080 environment: "development" debug: true enable_metrics: true enable_logging: true #+END_SRC

** Production #+BEGIN_SRC yaml host: "0.0.0.0" port: 443 environment: "production" debug: false enable_tls: true tls_cert_file: "/etc/ssl/certs/server.crt" tls_key_file: "/etc/ssl/private/server.key" read_timeout: "10s" write_timeout: "10s" #+END_SRC