Add project scaffolding with fx DI, SQLite migrations, and healthcheck

- go.mod with git.eeqj.de/sneak/chat module
- internal packages: globals, logger, config, db, healthcheck, middleware, handlers, server
- SQLite database with embedded migration system (schema_migrations tracking)
- Migration 001: schema_migrations table
- Migration 002: channels table
- Config with chat-specific vars (MAX_HISTORY, SESSION_TIMEOUT, MAX_MESSAGE_SIZE, MOTD, SERVER_NAME, FEDERATION_KEY)
- Healthcheck endpoint at /.well-known/healthcheck.json
- Makefile, .gitignore
- cmd/chatd/main.go entry point

internal/config/config.go

@@ -0,0 +1,96 @@
+package config
+
+import (
+	"fmt"
+	"log/slog"
+
+	"git.eeqj.de/sneak/chat/internal/globals"
+	"git.eeqj.de/sneak/chat/internal/logger"
+	"github.com/spf13/viper"
+	"go.uber.org/fx"
+
+	_ "github.com/joho/godotenv/autoload"
+)
+
+type ConfigParams struct {
+	fx.In
+	Globals *globals.Globals
+	Logger  *logger.Logger
+}
+
+type Config struct {
+	DBURL           string
+	Debug           bool
+	MaintenanceMode bool
+	MetricsPassword string
+	MetricsUsername  string
+	Port            int
+	SentryDSN       string
+	MaxHistory      int
+	SessionTimeout  int
+	MaxMessageSize  int
+	MOTD            string
+	ServerName      string
+	FederationKey   string
+	params          *ConfigParams
+	log             *slog.Logger
+}
+
+func New(lc fx.Lifecycle, params ConfigParams) (*Config, error) {
+	log := params.Logger.Get()
+	name := params.Globals.Appname
+
+	viper.SetConfigName(name)
+	viper.SetConfigType("yaml")
+	viper.AddConfigPath(fmt.Sprintf("/etc/%s", name))
+	viper.AddConfigPath(fmt.Sprintf("$HOME/.config/%s", name))
+	viper.AutomaticEnv()
+
+	viper.SetDefault("DEBUG", "false")
+	viper.SetDefault("MAINTENANCE_MODE", "false")
+	viper.SetDefault("PORT", "8080")
+	viper.SetDefault("DBURL", "file:./data.db?_journal_mode=WAL")
+	viper.SetDefault("SENTRY_DSN", "")
+	viper.SetDefault("METRICS_USERNAME", "")
+	viper.SetDefault("METRICS_PASSWORD", "")
+	viper.SetDefault("MAX_HISTORY", "10000")
+	viper.SetDefault("SESSION_TIMEOUT", "86400")
+	viper.SetDefault("MAX_MESSAGE_SIZE", "4096")
+	viper.SetDefault("MOTD", "")
+	viper.SetDefault("SERVER_NAME", "")
+	viper.SetDefault("FEDERATION_KEY", "")
+
+	if err := viper.ReadInConfig(); err != nil {
+		if _, ok := err.(viper.ConfigFileNotFoundError); ok {
+			// Config file not found is OK
+		} else {
+			log.Error("config file malformed", "error", err)
+			panic(err)
+		}
+	}
+
+	s := &Config{
+		DBURL:           viper.GetString("DBURL"),
+		Debug:           viper.GetBool("DEBUG"),
+		Port:            viper.GetInt("PORT"),
+		SentryDSN:       viper.GetString("SENTRY_DSN"),
+		MaintenanceMode: viper.GetBool("MAINTENANCE_MODE"),
+		MetricsUsername:  viper.GetString("METRICS_USERNAME"),
+		MetricsPassword: viper.GetString("METRICS_PASSWORD"),
+		MaxHistory:      viper.GetInt("MAX_HISTORY"),
+		SessionTimeout:  viper.GetInt("SESSION_TIMEOUT"),
+		MaxMessageSize:  viper.GetInt("MAX_MESSAGE_SIZE"),
+		MOTD:            viper.GetString("MOTD"),
+		ServerName:      viper.GetString("SERVER_NAME"),
+		FederationKey:   viper.GetString("FEDERATION_KEY"),
+		log:             log,
+		params:          &params,
+	}
+
+	if s.Debug {
+		params.Logger.EnableDebugLogging()
+		s.log = params.Logger.Get()
+	}
+
+	return s, nil
+}