feat: add trusted proxy identity and overload stats

config/config.go

@@ -4,6 +4,7 @@ import (
 	"strings"
 	"time"
 
+	"git.yuntuo.hk/k2safe/go-omni/httpx"
 	"git.yuntuo.hk/k2safe/go-omni/logx"
 )
 
@@ -14,6 +15,7 @@ type Config struct {
 	Address         string
 	RequestIDHeader string
 	EnableLogger    bool
+	TrustedProxies  []string
 	ShutdownTimeout time.Duration
 	Log             logx.Config
 }
@@ -38,6 +40,9 @@ func (c Config) Validate() error {
 	if c.ShutdownTimeout <= 0 {
 		return &ConfigError{Field: "shutdown_timeout", Message: "must be positive"}
 	}
+	if _, err := httpx.NewClientIPResolver(c.TrustedProxies...); err != nil {
+		return &ConfigError{Field: "trusted_proxies", Message: err.Error()}
+	}
 	return nil
 }
 
@@ -66,10 +71,22 @@ func WithLogger(enabled bool) Option {
 	return func(cfg *Config) { cfg.EnableLogger = enabled }
 }
 
+// WithTrustedProxies allows only these IPs/CIDRs to supply X-Forwarded-For.
+// An empty list disables forwarding-header trust. Invalid entries are rejected
+// by Config.Validate and panic when passed directly to App.New.
+func WithTrustedProxies(proxies ...string) Option {
+	proxies = append([]string(nil), proxies...)
+	return func(cfg *Config) { cfg.TrustedProxies = append([]string(nil), proxies...) }
+}
+
 // WithConfig applies a complete configuration loaded from a file or
 // environment. Later options can still override individual fields.
 func WithConfig(settings Config) Option {
-	return func(cfg *Config) { *cfg = settings }
+	settings.TrustedProxies = append([]string(nil), settings.TrustedProxies...)
+	return func(cfg *Config) {
+		*cfg = settings
+		cfg.TrustedProxies = append([]string(nil), settings.TrustedProxies...)
+	}
 }
 
 // WithLogConfig configures the logger used by the application runtime.

config/config_test.go

@@ -9,6 +9,7 @@ import (
 func TestLoadFromEnvUsesDefaults(t *testing.T) {
 	for _, key := range []string{
 		"GO_OMNI_HTTP_ADDR", "GO_OMNI_REQUEST_ID_HEADER", "GO_OMNI_ENABLE_LOGGER",
+		"GO_OMNI_TRUSTED_PROXIES",
 		"GO_OMNI_LOG_LEVEL", "GO_OMNI_LOG_FORMAT", "GO_OMNI_LOG_OUTPUT",
 		"GO_OMNI_LOG_FILE", "GO_OMNI_SERVICE", "GO_OMNI_ENVIRONMENT",
 		"GO_OMNI_LOG_ADD_SOURCE", "GO_OMNI_SHUTDOWN_TIMEOUT",
@@ -31,6 +32,7 @@ func TestLoadFromEnvUsesDefaults(t *testing.T) {
 func TestLoadFromEnvOverridesSettings(t *testing.T) {
 	t.Setenv("GO_OMNI_HTTP_ADDR", "127.0.0.1:9090")
 	t.Setenv("GO_OMNI_REQUEST_ID_HEADER", "X-Correlation-ID")
+	t.Setenv("GO_OMNI_TRUSTED_PROXIES", "127.0.0.1, 10.0.0.0/8")
 	t.Setenv("GO_OMNI_ENABLE_LOGGER", "true")
 	t.Setenv("GO_OMNI_LOG_LEVEL", "debug")
 	t.Setenv("GO_OMNI_LOG_FORMAT", "text")
@@ -44,7 +46,7 @@ func TestLoadFromEnvOverridesSettings(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if cfg.Address != "127.0.0.1:9090" || cfg.RequestIDHeader != "X-Correlation-ID" || !cfg.EnableLogger {
+	if cfg.Address != "127.0.0.1:9090" || cfg.RequestIDHeader != "X-Correlation-ID" || !cfg.EnableLogger || len(cfg.TrustedProxies) != 2 || cfg.TrustedProxies[1] != "10.0.0.0/8" {
 		t.Fatalf("unexpected application settings: %+v", cfg)
 	}
 	if cfg.ShutdownTimeout != 3*time.Second || cfg.Log.Level != "debug" || cfg.Log.Format != "text" || cfg.Log.Output != "stdout" || cfg.Log.Service != "billing" || cfg.Log.Environment != "test" || !cfg.Log.AddSource {
@@ -65,6 +67,11 @@ func TestLoadFromEnvRejectsInvalidValues(t *testing.T) {
 	}
 
 	t.Setenv("GO_OMNI_SHUTDOWN_TIMEOUT", "1s")
+	t.Setenv("GO_OMNI_TRUSTED_PROXIES", "proxy.example.com")
+	if _, err := LoadFromEnv(""); err == nil || !strings.Contains(err.Error(), "trusted_proxies") {
+		t.Fatalf("expected invalid trusted proxy error, got %v", err)
+	}
+	t.Setenv("GO_OMNI_TRUSTED_PROXIES", "")
 	cfg := Default()
 	cfg.Address = ""
 	if err := cfg.Validate(); err == nil || !strings.Contains(err.Error(), "address") {
@@ -80,11 +87,16 @@ func TestLoadFromEnvRejectsInvalidValues(t *testing.T) {
 func TestWithConfigAndWithLogConfig(t *testing.T) {
 	settings := Default()
 	settings.Log.Service = "orders"
+	settings.TrustedProxies = []string{"127.0.0.1"}
 	cfg := Default()
 	WithConfig(settings)(&cfg)
-	if cfg.Log.Service != "orders" {
+	if cfg.Log.Service != "orders" || len(cfg.TrustedProxies) != 1 {
 		t.Fatalf("complete config was not applied: %+v", cfg)
 	}
+	settings.TrustedProxies[0] = "10.0.0.0/8"
+	if cfg.TrustedProxies[0] != "127.0.0.1" {
+		t.Fatal("WithConfig should copy trusted proxy settings")
+	}
 
 	WithLogConfig(Default().Log)(&cfg)
 	if cfg.Log.Service != "" {

config/env.go

@@ -20,6 +20,12 @@ func LoadFromEnv(prefix string) (Config, error) {
 	cfg := Default()
 	cfg.Address = envString(prefix+"HTTP_ADDR", cfg.Address)
 	cfg.RequestIDHeader = envString(prefix+"REQUEST_ID_HEADER", cfg.RequestIDHeader)
+	if value := strings.TrimSpace(os.Getenv(prefix + "TRUSTED_PROXIES")); value != "" {
+		cfg.TrustedProxies = strings.Split(value, ",")
+		for i := range cfg.TrustedProxies {
+			cfg.TrustedProxies[i] = strings.TrimSpace(cfg.TrustedProxies[i])
+		}
+	}
 	cfg.Log.Level = envString(prefix+"LOG_LEVEL", cfg.Log.Level)
 	cfg.Log.Format = envString(prefix+"LOG_FORMAT", cfg.Log.Format)
 	cfg.Log.Output = envString(prefix+"LOG_OUTPUT", cfg.Log.Output)