package middleware import ( "fmt" "net/http" "runtime" "github.com/labstack/echo/v4" "github.com/labstack/gommon/log" ) type ( // LogErrorFunc defines a function for custom logging in the middleware. LogErrorFunc func(c echo.Context, err error, stack []byte) error // RecoverConfig defines the config for Recover middleware. RecoverConfig struct { // Skipper defines a function to skip middleware. Skipper Skipper // Size of the stack to be printed. // Optional. Default value 4KB. StackSize int `yaml:"stack_size"` // DisableStackAll disables formatting stack traces of all other goroutines // into buffer after the trace for the current goroutine. // Optional. Default value false. DisableStackAll bool `yaml:"disable_stack_all"` // DisablePrintStack disables printing stack trace. // Optional. Default value as false. DisablePrintStack bool `yaml:"disable_print_stack"` // LogLevel is log level to printing stack trace. // Optional. Default value 0 (Print). LogLevel log.Lvl // LogErrorFunc defines a function for custom logging in the middleware. // If it's set you don't need to provide LogLevel for config. LogErrorFunc LogErrorFunc } ) var ( // DefaultRecoverConfig is the default Recover middleware config. DefaultRecoverConfig = RecoverConfig{ Skipper: DefaultSkipper, StackSize: 4 << 10, // 4 KB DisableStackAll: false, DisablePrintStack: false, LogLevel: 0, LogErrorFunc: nil, } ) // Recover returns a middleware which recovers from panics anywhere in the chain // and handles the control to the centralized HTTPErrorHandler. func Recover() echo.MiddlewareFunc { return RecoverWithConfig(DefaultRecoverConfig) } // RecoverWithConfig returns a Recover middleware with config. // See: `Recover()`. func RecoverWithConfig(config RecoverConfig) echo.MiddlewareFunc { // Defaults if config.Skipper == nil { config.Skipper = DefaultRecoverConfig.Skipper } if config.StackSize == 0 { config.StackSize = DefaultRecoverConfig.StackSize } return func(next echo.HandlerFunc) echo.HandlerFunc { return func(c echo.Context) error { if config.Skipper(c) { return next(c) } defer func() { if r := recover(); r != nil { if r == http.ErrAbortHandler { panic(r) } err, ok := r.(error) if !ok { err = fmt.Errorf("%v", r) } var stack []byte var length int if !config.DisablePrintStack { stack = make([]byte, config.StackSize) length = runtime.Stack(stack, !config.DisableStackAll) stack = stack[:length] } if config.LogErrorFunc != nil { err = config.LogErrorFunc(c, err, stack) } else if !config.DisablePrintStack { msg := fmt.Sprintf("[PANIC RECOVER] %v %s\n", err, stack[:length]) switch config.LogLevel { case log.DEBUG: c.Logger().Debug(msg) case log.INFO: c.Logger().Info(msg) case log.WARN: c.Logger().Warn(msg) case log.ERROR: c.Logger().Error(msg) case log.OFF: // None. default: c.Logger().Print(msg) } } c.Error(err) } }() return next(c) } } }