135 lines
4.0 KiB
Go
135 lines
4.0 KiB
Go
// Copyright 2024, Google Inc.
|
|
// All rights reserved.
|
|
//
|
|
// Redistribution and use in source and binary forms, with or without
|
|
// modification, are permitted provided that the following conditions are
|
|
// met:
|
|
//
|
|
// * Redistributions of source code must retain the above copyright
|
|
// notice, this list of conditions and the following disclaimer.
|
|
// * Redistributions in binary form must reproduce the above
|
|
// copyright notice, this list of conditions and the following disclaimer
|
|
// in the documentation and/or other materials provided with the
|
|
// distribution.
|
|
// * Neither the name of Google Inc. nor the names of its
|
|
// contributors may be used to endorse or promote products derived from
|
|
// this software without specific prior written permission.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
// Package internal provides some common logic and types to other logging
|
|
// sub-packages.
|
|
package internal
|
|
|
|
import (
|
|
"context"
|
|
"io"
|
|
"log/slog"
|
|
"os"
|
|
"strings"
|
|
"time"
|
|
)
|
|
|
|
const (
|
|
// LoggingLevelEnvVar is the environment variable used to enable logging
|
|
// at a particular level.
|
|
LoggingLevelEnvVar = "GOOGLE_SDK_GO_LOGGING_LEVEL"
|
|
|
|
googLvlKey = "severity"
|
|
googMsgKey = "message"
|
|
googSourceKey = "sourceLocation"
|
|
googTimeKey = "timestamp"
|
|
)
|
|
|
|
// NewLoggerWithWriter is exposed for testing.
|
|
func NewLoggerWithWriter(w io.Writer) *slog.Logger {
|
|
lvl, loggingEnabled := checkLoggingLevel()
|
|
if !loggingEnabled {
|
|
return slog.New(noOpHandler{})
|
|
}
|
|
return slog.New(newGCPSlogHandler(lvl, w))
|
|
}
|
|
|
|
// checkLoggingLevel returned the configured logging level and whether or not
|
|
// logging is enabled.
|
|
func checkLoggingLevel() (slog.Leveler, bool) {
|
|
sLevel := strings.ToLower(os.Getenv(LoggingLevelEnvVar))
|
|
var level slog.Level
|
|
switch sLevel {
|
|
case "debug":
|
|
level = slog.LevelDebug
|
|
case "info":
|
|
level = slog.LevelInfo
|
|
case "warn":
|
|
level = slog.LevelWarn
|
|
case "error":
|
|
level = slog.LevelError
|
|
default:
|
|
return nil, false
|
|
}
|
|
return level, true
|
|
}
|
|
|
|
// newGCPSlogHandler returns a Handler that is configured to output in a JSON
|
|
// format with well-known keys. For more information on this format see
|
|
// https://cloud.google.com/logging/docs/agent/logging/configuration#special-fields.
|
|
func newGCPSlogHandler(lvl slog.Leveler, w io.Writer) slog.Handler {
|
|
return slog.NewJSONHandler(w, &slog.HandlerOptions{
|
|
Level: lvl,
|
|
ReplaceAttr: replaceAttr,
|
|
})
|
|
}
|
|
|
|
// replaceAttr remaps default Go logging keys to match what is expected in
|
|
// cloud logging.
|
|
func replaceAttr(groups []string, a slog.Attr) slog.Attr {
|
|
if groups == nil {
|
|
if a.Key == slog.LevelKey {
|
|
a.Key = googLvlKey
|
|
return a
|
|
} else if a.Key == slog.MessageKey {
|
|
a.Key = googMsgKey
|
|
return a
|
|
} else if a.Key == slog.SourceKey {
|
|
a.Key = googSourceKey
|
|
return a
|
|
} else if a.Key == slog.TimeKey {
|
|
a.Key = googTimeKey
|
|
if a.Value.Kind() == slog.KindTime {
|
|
a.Value = slog.StringValue(a.Value.Time().Format(time.RFC3339))
|
|
}
|
|
return a
|
|
}
|
|
}
|
|
return a
|
|
}
|
|
|
|
// The handler returned if logging is not enabled.
|
|
type noOpHandler struct{}
|
|
|
|
func (h noOpHandler) Enabled(_ context.Context, _ slog.Level) bool {
|
|
return false
|
|
}
|
|
|
|
func (h noOpHandler) Handle(_ context.Context, _ slog.Record) error {
|
|
return nil
|
|
}
|
|
|
|
func (h noOpHandler) WithAttrs(_ []slog.Attr) slog.Handler {
|
|
return h
|
|
}
|
|
|
|
func (h noOpHandler) WithGroup(_ string) slog.Handler {
|
|
return h
|
|
}
|