feat(config): 配置加载与 schema 校验（.env/env 注入 + 反射解码 + 校验）

internal/config/config.go

@@ -0,0 +1,137 @@
+// Package config loads, defaults, and validates the Cyrene v2 configuration
+// from environment variables and an optional .env file (development only).
+//
+// Every setting is sourced from an environment variable (no hard-coded values
+// in code). Nested groups map to struct fields tagged with `env:"NAME"`.
+// Missing required values cause Load/MustLoad to return an error so startup
+// can fail fast.
+package config
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// Config is the root configuration tree.
+type Config struct {
+	Env             string   `env:"ENV" default:"development"`
+	LogLevel        string   `env:"LOG_LEVEL" default:"debug"`
+	Timezone        string   `env:"TZ" default:"Asia/Shanghai"`
+	DataDir         string   `env:"DATA_DIR" default:"./data"`
+	AllowedOrigins  []string `env:"ALLOWED_ORIGINS" default:"http://localhost:5173,http://localhost:3000"`
+
+	Server    ServerConfig
+	Auth      AuthConfig
+	DB        DBConfig
+	LLM       LLMConfig
+	Embedding EmbeddingConfig
+	IoT       IoTConfig
+	Voice     VoiceConfig
+	Background BackgroundConfig
+	WSHub     WSHubConfig
+}
+
+// ServerConfig holds the single gateway listener settings.
+type ServerConfig struct {
+	Host string `env:"HOST" default:"0.0.0.0"`
+	Port int    `env:"PORT" default:"8080"`
+}
+
+// AuthConfig holds authentication and admin credential settings.
+type AuthConfig struct {
+	JWTSecret           string `env:"JWT_SECRET" validate:"required,min=32"`
+	AdminUser           string `env:"ADMIN_USERNAME" default:"admin"`
+	AdminPass           string `env:"ADMIN_PASSWORD" default:"admin12345"`
+	RegistrationEnabled bool   `env:"REGISTRATION_ENABLED" default:"true"`
+}
+
+// DBConfig holds database connection settings. SQLite is the default; PGURL is
+// the optional PostgreSQL+pgvector enhancement.
+type DBConfig struct {
+	SQLitePath string `env:"DB_SQLITE_PATH" default:"./data/cyrene.db"`
+	PGURL      string `env:"DB_PG_URL"`
+}
+
+// LLMConfig holds the multi-supplier LLM adapter settings.
+type LLMConfig struct {
+	BaseURL  string `env:"LLM_BASE_URL"`
+	APIKey   string `env:"LLM_API_KEY"`
+	Model    string `env:"LLM_MODEL"`
+	Fallback string `env:"LLM_FALLBACK_MODEL"`
+}
+
+// EmbeddingConfig holds the optional semantic embedding API settings. When
+// unset, the runtime falls back to built-in n-gram/FTS vectors.
+type EmbeddingConfig struct {
+	APIURL string `env:"EMBEDDING_API_URL"`
+	APIKey string `env:"EMBEDDING_API_KEY"`
+	Model  string `env:"EMBEDDING_MODEL"`
+}
+
+// IoTConfig selects the IoT device provider.
+type IoTConfig struct {
+	Provider string `env:"IOT_PROVIDER" default:"mock"`
+}
+
+// VoiceConfig holds TTS/STT provider settings.
+type VoiceConfig struct {
+	TTSProvider      string `env:"TTS_PROVIDER" default:"edge-tts"`
+	STTProvider      string `env:"STT_PROVIDER" default:"dashscope"`
+	DashscopeAPIKey  string `env:"DASHSCOPE_API_KEY"`
+}
+
+// BackgroundConfig holds the autonomous thinking settings.
+type BackgroundConfig struct {
+	Enabled         bool `env:"ENABLE_BACKGROUND_THINKING" default:"true"`
+	IntervalSec     int  `env:"THINK_INTERVAL_SEC" default:"300"`
+	SilenceTimeout  int  `env:"THINK_SILENCE_TIMEOUT_SEC" default:"120"`
+}
+
+// WSHubConfig holds the WebSocket hub limits.
+type WSHubConfig struct {
+	MaxConnections     int `env:"WS_MAX_CONNECTIONS" default:"1000"`
+	SessionIdleTimeout int `env:"SESSION_IDLE_TIMEOUT_MIN" default:"30"`
+}
+
+// Load reads configuration, merging an optional .env file (development only)
+// with process environment variables. Process environment variables always take
+// precedence over .env values, which take precedence over code defaults.
+//
+// Passing an empty envPath skips .env entirely. A missing .env file is not an
+// error; only missing required values are.
+func Load(envPath string) (*Config, error) {
+	fromEnv := map[string]string{}
+	if envPath != "" {
+		m, err := parseDotEnv(envPath)
+		if err != nil {
+			return nil, fmt.Errorf("config: read %s: %w", envPath, err)
+		}
+		fromEnv = m
+	}
+
+	cfg := &Config{}
+	if err := decodeValue(reflect.ValueOf(cfg), fromEnv); err != nil {
+		return nil, err
+	}
+
+	if errs := validateStruct(reflect.ValueOf(cfg).Elem()); len(errs) > 0 {
+		parts := make([]string, 0, len(errs))
+		for _, e := range errs {
+			parts = append(parts, e.Error())
+		}
+		return nil, fmt.Errorf("config: validation failed: %s", strings.Join(parts, "; "))
+	}
+
+	return cfg, nil
+}
+
+// MustLoad is Load that panics on error. It is intended for startup, matching
+// the "schema validation fails at boot" rule.
+func MustLoad(envPath string) *Config {
+	cfg, err := Load(envPath)
+	if err != nil {
+		panic(err)
+	}
+	return cfg
+}