104 lines
3.2 KiB
Go
104 lines
3.2 KiB
Go
// Copyright The OpenTelemetry Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package global // import "go.opentelemetry.io/otel/internal/global"
|
|
|
|
import (
|
|
"log"
|
|
"os"
|
|
"sync/atomic"
|
|
"unsafe"
|
|
)
|
|
|
|
var (
|
|
// GlobalErrorHandler provides an ErrorHandler that can be used
|
|
// throughout an OpenTelemetry instrumented project. When a user
|
|
// specified ErrorHandler is registered (`SetErrorHandler`) all calls to
|
|
// `Handle` and will be delegated to the registered ErrorHandler.
|
|
GlobalErrorHandler = defaultErrorHandler()
|
|
|
|
// Compile-time check that delegator implements ErrorHandler.
|
|
_ ErrorHandler = (*ErrDelegator)(nil)
|
|
// Compile-time check that errLogger implements ErrorHandler.
|
|
_ ErrorHandler = (*ErrLogger)(nil)
|
|
)
|
|
|
|
// ErrorHandler handles irremediable events.
|
|
type ErrorHandler interface {
|
|
// Handle handles any error deemed irremediable by an OpenTelemetry
|
|
// component.
|
|
Handle(error)
|
|
}
|
|
|
|
type ErrDelegator struct {
|
|
delegate unsafe.Pointer
|
|
}
|
|
|
|
func (d *ErrDelegator) Handle(err error) {
|
|
d.getDelegate().Handle(err)
|
|
}
|
|
|
|
func (d *ErrDelegator) getDelegate() ErrorHandler {
|
|
return *(*ErrorHandler)(atomic.LoadPointer(&d.delegate))
|
|
}
|
|
|
|
// setDelegate sets the ErrorHandler delegate.
|
|
func (d *ErrDelegator) setDelegate(eh ErrorHandler) {
|
|
atomic.StorePointer(&d.delegate, unsafe.Pointer(&eh))
|
|
}
|
|
|
|
func defaultErrorHandler() *ErrDelegator {
|
|
d := &ErrDelegator{}
|
|
d.setDelegate(&ErrLogger{l: log.New(os.Stderr, "", log.LstdFlags)})
|
|
return d
|
|
}
|
|
|
|
// ErrLogger logs errors if no delegate is set, otherwise they are delegated.
|
|
type ErrLogger struct {
|
|
l *log.Logger
|
|
}
|
|
|
|
// Handle logs err if no delegate is set, otherwise it is delegated.
|
|
func (h *ErrLogger) Handle(err error) {
|
|
h.l.Print(err)
|
|
}
|
|
|
|
// GetErrorHandler returns the global ErrorHandler instance.
|
|
//
|
|
// The default ErrorHandler instance returned will log all errors to STDERR
|
|
// until an override ErrorHandler is set with SetErrorHandler. All
|
|
// ErrorHandler returned prior to this will automatically forward errors to
|
|
// the set instance instead of logging.
|
|
//
|
|
// Subsequent calls to SetErrorHandler after the first will not forward errors
|
|
// to the new ErrorHandler for prior returned instances.
|
|
func GetErrorHandler() ErrorHandler {
|
|
return GlobalErrorHandler
|
|
}
|
|
|
|
// SetErrorHandler sets the global ErrorHandler to h.
|
|
//
|
|
// The first time this is called all ErrorHandler previously returned from
|
|
// GetErrorHandler will send errors to h instead of the default logging
|
|
// ErrorHandler. Subsequent calls will set the global ErrorHandler, but not
|
|
// delegate errors to h.
|
|
func SetErrorHandler(h ErrorHandler) {
|
|
GlobalErrorHandler.setDelegate(h)
|
|
}
|
|
|
|
// Handle is a convenience function for ErrorHandler().Handle(err).
|
|
func Handle(err error) {
|
|
GetErrorHandler().Handle(err)
|
|
}
|