Xray-core/common/errors/errors.go
2020-12-05 04:39:58 +00:00

204 lines
3.8 KiB
Go

// Package errors is a drop-in replacement for Golang lib 'errors'.
package errors // import "github.com/xtls/xray-core/common/errors"
import (
"os"
"reflect"
"strings"
"github.com/xtls/xray-core/common/log"
"github.com/xtls/xray-core/common/serial"
)
const trim = len("github.com/xtls/xray-core/")
type hasInnerError interface {
// Inner returns the underlying error of this one.
Inner() error
}
type hasSeverity interface {
Severity() log.Severity
}
// Error is an error object with underlying error.
type Error struct {
pathObj interface{}
prefix []interface{}
message []interface{}
inner error
severity log.Severity
}
func (err *Error) WithPathObj(obj interface{}) *Error {
err.pathObj = obj
return err
}
func (err *Error) pkgPath() string {
if err.pathObj == nil {
return ""
}
path := reflect.TypeOf(err.pathObj).PkgPath()
for i := 0; i < len(path); i++ {
if path[i] == '/' {
return path[trim:]
}
}
return path
}
// Error implements error.Error().
func (err *Error) Error() string {
builder := strings.Builder{}
for _, prefix := range err.prefix {
builder.WriteByte('[')
builder.WriteString(serial.ToString(prefix))
builder.WriteString("] ")
}
path := err.pkgPath()
if len(path) > 0 {
builder.WriteString(path)
builder.WriteString(": ")
}
msg := serial.Concat(err.message...)
builder.WriteString(msg)
if err.inner != nil {
builder.WriteString(" > ")
builder.WriteString(err.inner.Error())
}
return builder.String()
}
// Inner implements hasInnerError.Inner()
func (err *Error) Inner() error {
if err.inner == nil {
return nil
}
return err.inner
}
func (err *Error) Base(e error) *Error {
err.inner = e
return err
}
func (err *Error) atSeverity(s log.Severity) *Error {
err.severity = s
return err
}
func (err *Error) Severity() log.Severity {
if err.inner == nil {
return err.severity
}
if s, ok := err.inner.(hasSeverity); ok {
as := s.Severity()
if as < err.severity {
return as
}
}
return err.severity
}
// AtDebug sets the severity to debug.
func (err *Error) AtDebug() *Error {
return err.atSeverity(log.Severity_Debug)
}
// AtInfo sets the severity to info.
func (err *Error) AtInfo() *Error {
return err.atSeverity(log.Severity_Info)
}
// AtWarning sets the severity to warning.
func (err *Error) AtWarning() *Error {
return err.atSeverity(log.Severity_Warning)
}
// AtError sets the severity to error.
func (err *Error) AtError() *Error {
return err.atSeverity(log.Severity_Error)
}
// String returns the string representation of this error.
func (err *Error) String() string {
return err.Error()
}
// WriteToLog writes current error into log.
func (err *Error) WriteToLog(opts ...ExportOption) {
var holder ExportOptionHolder
for _, opt := range opts {
opt(&holder)
}
if holder.SessionID > 0 {
err.prefix = append(err.prefix, holder.SessionID)
}
log.Record(&log.GeneralMessage{
Severity: GetSeverity(err),
Content: err,
})
}
type ExportOptionHolder struct {
SessionID uint32
}
type ExportOption func(*ExportOptionHolder)
// New returns a new error object with message formed from given arguments.
func New(msg ...interface{}) *Error {
return &Error{
message: msg,
severity: log.Severity_Info,
}
}
// Cause returns the root cause of this error.
func Cause(err error) error {
if err == nil {
return nil
}
L:
for {
switch inner := err.(type) {
case hasInnerError:
if inner.Inner() == nil {
break L
}
err = inner.Inner()
case *os.PathError:
if inner.Err == nil {
break L
}
err = inner.Err
case *os.SyscallError:
if inner.Err == nil {
break L
}
err = inner.Err
default:
break L
}
}
return err
}
// GetSeverity returns the actual severity of the error, including inner errors.
func GetSeverity(err error) log.Severity {
if s, ok := err.(hasSeverity); ok {
return s.Severity()
}
return log.Severity_Info
}