feat: multiple machines support

[daltonbr]

Multi-device support with YAML configuration

Closes #1

Breaking Changes:

• Replaced environment variable configuration with YAML-based config
• /wake endpoint now requires either device or mac+ip parameters (no default device)

Features:

• Support multiple devices via YAML configuration (env var or file)
• Two configuration methods: WOL_CONFIG env var (Docker) or ~/.config/wol-server/config.yaml (bare metal)
• Two wake modes: configured device lookup (?device=name) or direct parameters (?mac=...&ip=...)
• Removed unnecessary broadcast parameter (determined by IP address)

Implementation:

• Extracted buildMagicPacket() as testable pure function
• Added several validation around inputs
• Added comprehensive test suite (tests covering config, handlers, and WOL logic)
• Multi-arch Docker support (linux/amd64, linux/arm64)

Dependencies:

• Added: gopkg.in/yaml.v3
• Removed: github.com/joho/godotenv

Documentation:

• Refactored documentation: user-focused README.md + separate DEVELOPMENT.md
• Streamlined README for end users
• Added macOS Docker networking notes

[Copilot]

Pull request overview

This PR refactors the WOL server from environment variable-based configuration to YAML-based configuration, adding support for managing multiple devices. The refactor introduces a cleaner API that allows both named device lookups and direct parameter-based wake requests.

Key Changes

• Replaced environment variable configuration with YAML-based config supporting multiple named devices
• Added dual API modes: device lookup by name or direct parameters (MAC, IP, port, broadcast)
• Extracted buildMagicPacket function for better testability and code organization

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
go.mod	Updated dependencies from godotenv to yaml.v3 for YAML parsing
config.go	Complete rewrite implementing YAML-based configuration with device lookup and default handling
config_test.go	New comprehensive test suite for configuration loading from env and file sources
main.go	Refactored handler to support both device-based and direct parameter-based wake requests
wol.go	Extracted buildMagicPacket function for improved testability
wol_test.go	New test suite for magic packet construction and validation
handlers_test.go	New HTTP handler tests covering various parameter combinations and error cases
config.example.yaml	New example configuration file demonstrating multi-device setup
README.md	Updated documentation with new API examples and configuration instructions
docs/DEVELOPMENT.md	New development guide with build, test, and deployment instructions
dockerfile	Removed hardcoded environment variables now handled via config
.gitignore	Added wol-server binary to ignored files
.cspell.json	Removed obsolete godotenv-related words from spell check dictionary

Comments suppressed due to low confidence (2)

main.go:83

• The handler does not validate the HTTP method. While the documentation shows GET requests, the handler will accept POST, PUT, DELETE, etc. without any validation. Consider adding an HTTP method check at the beginning of the handler to only allow GET requests and return 405 Method Not Allowed for other methods, following REST best practices.

func handler(w http.ResponseWriter, r *http.Request) {
	query := r.URL.Query()

	var config WOLConfig
	var err error

	// Check if device parameter is provided (lookup in config)
	if deviceName := query.Get("device"); deviceName != "" {
		config, err = getDeviceConfig(deviceName)
		if err != nil {
			log.Printf("Error getting device config: %v", err)
			http.Error(w, fmt.Sprintf("Device not found: %s", deviceName), http.StatusNotFound)
			return
		}
	} else if mac := query.Get("mac"); mac != "" {
		// Direct parameters provided
		ip := query.Get("ip")
		if ip == "" {
			http.Error(w, "Missing required parameter: ip", http.StatusBadRequest)
			return
		}

		port := 9 // default
		if portStr := query.Get("port"); portStr != "" {
			if p, err := strconv.Atoi(portStr); err == nil {
				port = p
			}
		}

		broadcast := true // default
		if broadcastStr := query.Get("broadcast"); broadcastStr != "" {
			broadcast = broadcastStr == "true"
		}

		// Validate MAC address format
		if _, err := net.ParseMAC(mac); err != nil {
			http.Error(w, fmt.Sprintf("Invalid MAC address: %s", mac), http.StatusBadRequest)
			return
		}

		config = WOLConfig{
			MACAddress: mac,
			IPAddress:  ip,
			Port:       port,
			Broadcast:  broadcast,
		}
	} else {
		http.Error(w, "Missing required parameter: either 'device' or 'mac' and 'ip' must be provided", http.StatusBadRequest)
		return
	}

	err = sendMagicPacket(config)

	if err != nil {
		log.Printf("Error sending magic packet: %v", err)
		http.Error(w, "Failed to send magic packet", http.StatusInternalServerError)
		return
	}

	fmt.Fprintf(w, "Magic packet sent to %s", config.MACAddress)
}

wol.go:60

• The Broadcast field from the WOLConfig is not being used when sending the magic packet. The field is accepted in the configuration and API parameters, but the actual UDP socket doesn't have broadcast mode enabled based on this field. This means the broadcast parameter has no effect. Consider using syscall.SetsockoptInt to enable SO_BROADCAST on the connection when config.Broadcast is true, or remove the unused field from the configuration.

func sendMagicPacket(config WOLConfig) error {
	packet, err := buildMagicPacket(config.MACAddress)
	if err != nil {
		return err
	}

	// Set destination
	addr := net.UDPAddr{
		IP:   net.ParseIP(config.IPAddress),
		Port: config.Port,
	}

	log.Printf("Sending magic packet to %s via %s:%d",
		config.MACAddress, config.IPAddress, config.Port)

	conn, err := net.DialUDP("udp", nil, &addr)
	if err != nil {
		return fmt.Errorf("could not dial UDP: %w", err)
	}
	defer conn.Close()

	// Enable broadcast (important!)
	if err := conn.SetWriteBuffer(len(packet)); err != nil {
		return fmt.Errorf("set write buffer failed: %w", err)
	}

	if _, err := conn.Write(packet); err != nil {
		return fmt.Errorf("write to UDP failed: %w", err)
	}

	return nil
}

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[Copilot]

Pull request overview

Copilot reviewed 12 out of 13 changed files in this pull request and generated 3 comments.

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