webhooker/internal/config/config.go

package config

import (
	"fmt"
	"log/slog"
	"os"

	"go.uber.org/fx"
	"sneak.berlin/go/webhooker/internal/globals"
	"sneak.berlin/go/webhooker/internal/logger"
	pkgconfig "sneak.berlin/go/webhooker/pkg/config"

	// spooky action at a distance!
	// this populates the environment
	// from a ./.env file automatically
	// for development configuration.
	// .env contents should be things like
	// `DBURL=postgres://user:pass@.../`
	// (without the backticks, of course)
	_ "github.com/joho/godotenv/autoload"
)

const (
	// EnvironmentDev represents development environment
	EnvironmentDev = "dev"
	// EnvironmentProd represents production environment
	EnvironmentProd = "prod"
	// DevSessionKey is an insecure default session key for development
	// This is "webhooker-dev-session-key-insecure!" base64 encoded
	DevSessionKey = "d2ViaG9va2VyLWRldi1zZXNzaW9uLWtleS1pbnNlY3VyZSE="
)

// nolint:revive // ConfigParams is a standard fx naming convention
type ConfigParams struct {
	fx.In
	Globals *globals.Globals
	Logger  *logger.Logger
}

type Config struct {
	DBURL            string
	Debug            bool
	MaintenanceMode  bool
	DevelopmentMode  bool
	DevAdminUsername string
	DevAdminPassword string
	Environment      string
	MetricsPassword  string
	MetricsUsername  string
	Port             int
	SentryDSN        string
	SessionKey       string
	params           *ConfigParams
	log              *slog.Logger
}

// IsDev returns true if running in development environment
func (c *Config) IsDev() bool {
	return c.Environment == EnvironmentDev
}

// IsProd returns true if running in production environment
func (c *Config) IsProd() bool {
	return c.Environment == EnvironmentProd
}

// nolint:revive // lc parameter is required by fx even if unused
func New(lc fx.Lifecycle, params ConfigParams) (*Config, error) {
	log := params.Logger.Get()

	// Determine environment from WEBHOOKER_ENVIRONMENT env var, default to dev
	environment := os.Getenv("WEBHOOKER_ENVIRONMENT")
	if environment == "" {
		environment = EnvironmentDev
	}

	// Validate environment
	if environment != EnvironmentDev && environment != EnvironmentProd {
		return nil, fmt.Errorf("WEBHOOKER_ENVIRONMENT must be either '%s' or '%s', got '%s'",
			EnvironmentDev, EnvironmentProd, environment)
	}

	// Set the environment in the config package
	pkgconfig.SetEnvironment(environment)

	// Load configuration values
	s := &Config{
		DBURL:            pkgconfig.GetString("dburl"),
		Debug:            pkgconfig.GetBool("debug"),
		MaintenanceMode:  pkgconfig.GetBool("maintenanceMode"),
		DevelopmentMode:  pkgconfig.GetBool("developmentMode"),
		DevAdminUsername: pkgconfig.GetString("devAdminUsername"),
		DevAdminPassword: pkgconfig.GetString("devAdminPassword"),
		Environment:      pkgconfig.GetString("environment", environment),
		MetricsUsername:  pkgconfig.GetString("metricsUsername"),
		MetricsPassword:  pkgconfig.GetString("metricsPassword"),
		Port:             pkgconfig.GetInt("port", 8080),
		SentryDSN:        pkgconfig.GetSecretString("sentryDSN"),
		SessionKey:       pkgconfig.GetSecretString("sessionKey"),
		log:              log,
		params:           &params,
	}

	// Validate database URL
	if s.DBURL == "" {
		return nil, fmt.Errorf("database URL (dburl) is required")
	}

	// In production, require session key
	if s.IsProd() && s.SessionKey == "" {
		return nil, fmt.Errorf("SESSION_KEY is required in production environment")
	}

	// In development mode, warn if using default session key
	if s.IsDev() && s.SessionKey == DevSessionKey {
		log.Warn("Using insecure default session key for development mode")
	}

	if s.Debug {
		params.Logger.EnableDebugLogging()
		s.log = params.Logger.Get()
		log.Debug("Debug mode enabled")
	}

	// Log configuration summary (without secrets)
	log.Info("Configuration loaded",
		"environment", s.Environment,
		"port", s.Port,
		"debug", s.Debug,
		"maintenanceMode", s.MaintenanceMode,
		"developmentMode", s.DevelopmentMode,
		"hasSessionKey", s.SessionKey != "",
		"hasSentryDSN", s.SentryDSN != "",
		"hasMetricsAuth", s.MetricsUsername != "" && s.MetricsPassword != "",
	)

	return s, nil
}