2020-05-29 22:30:11 +02:00
|
|
|
// 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 (
|
|
|
|
"log"
|
|
|
|
"os"
|
|
|
|
"sync"
|
2020-06-01 20:50:35 +02:00
|
|
|
"sync/atomic"
|
2020-05-29 22:30:11 +02:00
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
"go.opentelemetry.io/otel"
|
2020-05-29 22:30:11 +02:00
|
|
|
)
|
|
|
|
|
2020-06-01 19:38:05 +02:00
|
|
|
var (
|
2020-08-05 19:31:42 +02:00
|
|
|
// 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 = &loggingErrorHandler{
|
2020-06-01 19:38:05 +02:00
|
|
|
l: log.New(os.Stderr, "", log.LstdFlags),
|
|
|
|
}
|
2020-05-30 00:34:53 +02:00
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// delegateErrorHandlerOnce ensures that a user provided ErrorHandler is
|
|
|
|
// only ever registered once.
|
|
|
|
delegateErrorHandlerOnce sync.Once
|
2020-06-01 20:50:35 +02:00
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// Comiple time check that loggingErrorHandler implements ErrorHandler.
|
|
|
|
_ otel.ErrorHandler = (*loggingErrorHandler)(nil)
|
2020-06-01 19:38:05 +02:00
|
|
|
)
|
2020-05-29 22:30:11 +02:00
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// loggingErrorHandler logs all errors to STDERR.
|
|
|
|
type loggingErrorHandler struct {
|
2020-06-01 20:50:35 +02:00
|
|
|
delegate atomic.Value
|
2020-05-29 22:30:11 +02:00
|
|
|
|
|
|
|
l *log.Logger
|
|
|
|
}
|
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// setDelegate sets the ErrorHandler delegate if one is not already set.
|
|
|
|
func (h *loggingErrorHandler) setDelegate(d otel.ErrorHandler) {
|
2020-06-01 20:50:35 +02:00
|
|
|
if h.delegate.Load() != nil {
|
|
|
|
// Delegate already registered
|
2020-05-29 22:30:11 +02:00
|
|
|
return
|
|
|
|
}
|
2020-06-01 20:50:35 +02:00
|
|
|
h.delegate.Store(d)
|
2020-05-29 22:30:11 +02:00
|
|
|
}
|
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// Handle implements otel.ErrorHandler.
|
|
|
|
func (h *loggingErrorHandler) Handle(err error) {
|
2020-06-01 20:50:35 +02:00
|
|
|
if d := h.delegate.Load(); d != nil {
|
2020-08-05 19:31:42 +02:00
|
|
|
d.(otel.ErrorHandler).Handle(err)
|
2020-05-29 22:30:11 +02:00
|
|
|
return
|
|
|
|
}
|
|
|
|
h.l.Print(err)
|
|
|
|
}
|
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// ErrorHandler returns the global ErrorHandler instance. If no ErrorHandler
|
|
|
|
// instance has been set (`SetErrorHandler`), the default ErrorHandler which
|
|
|
|
// logs errors to STDERR is returned.
|
|
|
|
func ErrorHandler() otel.ErrorHandler {
|
|
|
|
return globalErrorHandler
|
2020-05-29 22:30:11 +02:00
|
|
|
}
|
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// SetErrorHandler sets the global ErrorHandler to be h.
|
|
|
|
func SetErrorHandler(h otel.ErrorHandler) {
|
|
|
|
delegateErrorHandlerOnce.Do(func() {
|
|
|
|
current := ErrorHandler()
|
2020-06-01 20:50:35 +02:00
|
|
|
if current == h {
|
|
|
|
return
|
|
|
|
}
|
2020-08-05 19:31:42 +02:00
|
|
|
if internalHandler, ok := current.(*loggingErrorHandler); ok {
|
2020-06-01 20:50:35 +02:00
|
|
|
internalHandler.setDelegate(h)
|
|
|
|
}
|
|
|
|
})
|
2020-05-29 22:30:11 +02:00
|
|
|
}
|
2020-05-30 00:34:53 +02:00
|
|
|
|
2020-08-05 19:31:42 +02:00
|
|
|
// Handle is a convience function for ErrorHandler().Handle(err)
|
2020-05-30 00:34:53 +02:00
|
|
|
func Handle(err error) {
|
2020-08-05 19:31:42 +02:00
|
|
|
ErrorHandler().Handle(err)
|
2020-05-30 00:34:53 +02:00
|
|
|
}
|