package main import ( "flag" "fmt" "io" "os" "strconv" "strings" auto "github.com/tendermint/tendermint/libs/autofile" tmos "github.com/tendermint/tendermint/libs/os" ) const Version = "0.0.1" const readBufferSize = 1024 // 1KB at a time // Parse command-line options func parseFlags() (headPath string, chopSize int64, limitSize int64, version bool) { var flagSet = flag.NewFlagSet(os.Args[0], flag.ExitOnError) var chopSizeStr, limitSizeStr string flagSet.StringVar(&headPath, "head", "logjack.out", "Destination (head) file.") flagSet.StringVar(&chopSizeStr, "chop", "100M", "Move file if greater than this") flagSet.StringVar(&limitSizeStr, "limit", "10G", "Only keep this much (for each specified file). Remove old files.") flagSet.BoolVar(&version, "version", false, "Version") if err := flagSet.Parse(os.Args[1:]); err != nil { fmt.Printf("err parsing flag: %v\n", err) os.Exit(1) } chopSize = parseBytesize(chopSizeStr) limitSize = parseBytesize(limitSizeStr) return } type fmtLogger struct{} func (fmtLogger) Info(msg string, keyvals ...interface{}) { strs := make([]string, len(keyvals)) for i, kv := range keyvals { strs[i] = fmt.Sprintf("%v", kv) } fmt.Printf("%s %s\n", msg, strings.Join(strs, ",")) } func main() { // Stop upon receiving SIGTERM or CTRL-C. tmos.TrapSignal(fmtLogger{}, func() { fmt.Println("logjack shutting down") }) // Read options headPath, chopSize, limitSize, version := parseFlags() if version { fmt.Printf("logjack version %v\n", Version) return } // Open Group group, err := auto.OpenGroup(headPath, auto.GroupHeadSizeLimit(chopSize), auto.GroupTotalSizeLimit(limitSize)) if err != nil { fmt.Printf("logjack couldn't create output file %v\n", headPath) os.Exit(1) } if err = group.Start(); err != nil { fmt.Printf("logjack couldn't start with file %v\n", headPath) os.Exit(1) } // Forever read from stdin and write to AutoFile. buf := make([]byte, readBufferSize) for { n, err := os.Stdin.Read(buf) if err != nil { if err := group.Stop(); err != nil { fmt.Fprintf(os.Stderr, "logjack stopped with error %v\n", headPath) os.Exit(1) } if err == io.EOF { os.Exit(0) } else { fmt.Println("logjack errored") os.Exit(1) } } _, err = group.Write(buf[:n]) if err != nil { fmt.Fprintf(os.Stderr, "logjack failed write with error %v\n", headPath) os.Exit(1) } if err := group.FlushAndSync(); err != nil { fmt.Fprintf(os.Stderr, "logjack flushsync fail with error %v\n", headPath) os.Exit(1) } } } func parseBytesize(chopSize string) int64 { // Handle suffix multiplier var multiplier int64 = 1 if strings.HasSuffix(chopSize, "T") { multiplier = 1042 * 1024 * 1024 * 1024 chopSize = chopSize[:len(chopSize)-1] } if strings.HasSuffix(chopSize, "G") { multiplier = 1042 * 1024 * 1024 chopSize = chopSize[:len(chopSize)-1] } if strings.HasSuffix(chopSize, "M") { multiplier = 1042 * 1024 chopSize = chopSize[:len(chopSize)-1] } if strings.HasSuffix(chopSize, "K") { multiplier = 1042 chopSize = chopSize[:len(chopSize)-1] } // Parse the numeric part chopSizeInt, err := strconv.Atoi(chopSize) if err != nil { panic(err) } return int64(chopSizeInt) * multiplier }