Files
go-omni/logx/rotation.go

95 lines
2.4 KiB
Go

package logx
import (
"fmt"
"io"
"os"
"path/filepath"
"sync"
"gopkg.in/natefinch/lumberjack.v2"
"git.yuntuo.hk/k2safe/go-omni/internal/configdiag"
)
// RotationConfig opts a file logger into size-based rotation. Zero limits use
// 100 MiB, 10 backups and 7 days. Each file must have a single process owner.
type RotationConfig struct {
Enabled bool `json:"enabled"`
MaxSizeMB int `json:"maxSizeMb"`
MaxBackups int `json:"maxBackups"`
MaxAgeDays int `json:"maxAgeDays"`
Compress bool `json:"compress"`
}
func (r RotationConfig) validate(cfg Config) error {
for _, f := range []struct {
name string
value, max int
}{{"maxSizeMb", r.MaxSizeMB, 1024 * 1024}, {"maxBackups", r.MaxBackups, 10000}, {"maxAgeDays", r.MaxAgeDays, 36500}} {
if f.value < 0 || f.value > f.max {
return configdiag.New("rotation."+f.name, fmt.Sprintf("must be between 0 and %d", f.max))
}
}
if r.Enabled && cfg.File == "" {
return configdiag.New("file", "is required when rotation is enabled")
}
if r.Enabled && cfg.Writer != nil {
return configdiag.New("rotation.enabled", "cannot be enabled with a custom writer")
}
return nil
}
func rotatingWriter(cfg Config) (io.Writer, func() error, error) {
r := cfg.Rotation
if r.MaxSizeMB == 0 {
r.MaxSizeMB = 100
}
if r.MaxBackups == 0 {
r.MaxBackups = 10
}
if r.MaxAgeDays == 0 {
r.MaxAgeDays = 7
}
if err := os.MkdirAll(filepath.Dir(cfg.File), 0700); err != nil {
return nil, nil, err
}
// Fail at setup, rather than silently dropping the first log record.
f, err := os.OpenFile(cfg.File, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600)
if err != nil {
return nil, nil, err
}
if err = f.Close(); err != nil {
return nil, nil, err
}
w := &rotationWriter{writer: &lumberjack.Logger{Filename: cfg.File, MaxSize: r.MaxSizeMB, MaxBackups: r.MaxBackups, MaxAge: r.MaxAgeDays, Compress: r.Compress}}
return w, w.Close, nil
}
// Lumberjack can reopen after Close; prevent children of a closed logger from
// resurrecting its file. The lock also serializes shutdown with pending writes.
type rotationWriter struct {
mu sync.Mutex
writer *lumberjack.Logger
closed bool
}
func (w *rotationWriter) Write(p []byte) (int, error) {
w.mu.Lock()
defer w.mu.Unlock()
if w.closed {
return 0, io.ErrClosedPipe
}
return w.writer.Write(p)
}
func (w *rotationWriter) Close() error {
w.mu.Lock()
defer w.mu.Unlock()
if w.closed {
return nil
}
w.closed = true
return w.writer.Close()
}