package hclog import ( "bufio" "encoding" "encoding/json" "fmt" "log" "os" "runtime" "strconv" "strings" "sync" "time" ) var ( _levelToBracket = map[Level]string{ Debug: "[DEBUG]", Trace: "[TRACE]", Info: "[INFO ]", Warn: "[WARN ]", Error: "[ERROR]", } ) // Given the options (nil for defaults), create a new Logger func New(opts *LoggerOptions) Logger { if opts == nil { opts = &LoggerOptions{} } output := opts.Output if output == nil { output = os.Stderr } level := opts.Level if level == NoLevel { level = DefaultLevel } mtx := opts.Mutex if mtx == nil { mtx = new(sync.Mutex) } return &intLogger{ m: mtx, json: opts.JSONFormat, caller: opts.IncludeLocation, name: opts.Name, w: bufio.NewWriter(output), level: level, } } // The internal logger implementation. Internal in that it is defined entirely // by this package. type intLogger struct { json bool caller bool name string // this is a pointer so that it's shared by any derived loggers, since // those derived loggers share the bufio.Writer as well. m *sync.Mutex w *bufio.Writer level Level implied []interface{} } // Make sure that intLogger is a Logger var _ Logger = &intLogger{} // The time format to use for logging. This is a version of RFC3339 that // contains millisecond precision const TimeFormat = "2006-01-02T15:04:05.000Z0700" // Log a message and a set of key/value pairs if the given level is at // or more severe that the threshold configured in the Logger. func (z *intLogger) Log(level Level, msg string, args ...interface{}) { if level < z.level { return } t := time.Now() z.m.Lock() defer z.m.Unlock() if z.json { z.logJson(t, level, msg, args...) } else { z.log(t, level, msg, args...) } z.w.Flush() } // Cleanup a path by returning the last 2 segments of the path only. func trimCallerPath(path string) string { // lovely borrowed from zap // nb. To make sure we trim the path correctly on Windows too, we // counter-intuitively need to use '/' and *not* os.PathSeparator here, // because the path given originates from Go stdlib, specifically // runtime.Caller() which (as of Mar/17) returns forward slashes even on // Windows. // // See https://github.com/golang/go/issues/3335 // and https://github.com/golang/go/issues/18151 // // for discussion on the issue on Go side. // // Find the last separator. // idx := strings.LastIndexByte(path, '/') if idx == -1 { return path } // Find the penultimate separator. idx = strings.LastIndexByte(path[:idx], '/') if idx == -1 { return path } return path[idx+1:] } // Non-JSON logging format function func (z *intLogger) log(t time.Time, level Level, msg string, args ...interface{}) { z.w.WriteString(t.Format(TimeFormat)) z.w.WriteByte(' ') s, ok := _levelToBracket[level] if ok { z.w.WriteString(s) } else { z.w.WriteString("[UNKN ]") } if z.caller { if _, file, line, ok := runtime.Caller(3); ok { z.w.WriteByte(' ') z.w.WriteString(trimCallerPath(file)) z.w.WriteByte(':') z.w.WriteString(strconv.Itoa(line)) z.w.WriteByte(':') } } z.w.WriteByte(' ') if z.name != "" { z.w.WriteString(z.name) z.w.WriteString(": ") } z.w.WriteString(msg) args = append(z.implied, args...) var stacktrace CapturedStacktrace if args != nil && len(args) > 0 { if len(args)%2 != 0 { cs, ok := args[len(args)-1].(CapturedStacktrace) if ok { args = args[:len(args)-1] stacktrace = cs } else { args = append(args, "") } } z.w.WriteByte(':') FOR: for i := 0; i < len(args); i = i + 2 { var val string switch st := args[i+1].(type) { case string: val = st case int: val = strconv.FormatInt(int64(st), 10) case int64: val = strconv.FormatInt(int64(st), 10) case int32: val = strconv.FormatInt(int64(st), 10) case int16: val = strconv.FormatInt(int64(st), 10) case int8: val = strconv.FormatInt(int64(st), 10) case uint: val = strconv.FormatUint(uint64(st), 10) case uint64: val = strconv.FormatUint(uint64(st), 10) case uint32: val = strconv.FormatUint(uint64(st), 10) case uint16: val = strconv.FormatUint(uint64(st), 10) case uint8: val = strconv.FormatUint(uint64(st), 10) case CapturedStacktrace: stacktrace = st continue FOR default: val = fmt.Sprintf("%v", st) } z.w.WriteByte(' ') z.w.WriteString(args[i].(string)) z.w.WriteByte('=') if strings.ContainsAny(val, " \t\n\r") { z.w.WriteByte('"') z.w.WriteString(val) z.w.WriteByte('"') } else { z.w.WriteString(val) } } } z.w.WriteString("\n") if stacktrace != "" { z.w.WriteString(string(stacktrace)) } } // JSON logging function func (z *intLogger) logJson(t time.Time, level Level, msg string, args ...interface{}) { vals := map[string]interface{}{ "@message": msg, "@timestamp": t.Format("2006-01-02T15:04:05.000000Z07:00"), } var levelStr string switch level { case Error: levelStr = "error" case Warn: levelStr = "warn" case Info: levelStr = "info" case Debug: levelStr = "debug" case Trace: levelStr = "trace" default: levelStr = "all" } vals["@level"] = levelStr if z.name != "" { vals["@module"] = z.name } if z.caller { if _, file, line, ok := runtime.Caller(3); ok { vals["@caller"] = fmt.Sprintf("%s:%d", file, line) } } if args != nil && len(args) > 0 { if len(args)%2 != 0 { cs, ok := args[len(args)-1].(CapturedStacktrace) if ok { args = args[:len(args)-1] vals["stacktrace"] = cs } else { args = append(args, "") } } for i := 0; i < len(args); i = i + 2 { if _, ok := args[i].(string); !ok { // As this is the logging function not much we can do here // without injecting into logs... continue } val := args[i+1] // Check if val is of type error. If error type doesn't // implement json.Marshaler or encoding.TextMarshaler // then set val to err.Error() so that it gets marshaled if err, ok := val.(error); ok { switch err.(type) { case json.Marshaler, encoding.TextMarshaler: default: val = err.Error() } } vals[args[i].(string)] = val } } err := json.NewEncoder(z.w).Encode(vals) if err != nil { panic(err) } } // Emit the message and args at DEBUG level func (z *intLogger) Debug(msg string, args ...interface{}) { z.Log(Debug, msg, args...) } // Emit the message and args at TRACE level func (z *intLogger) Trace(msg string, args ...interface{}) { z.Log(Trace, msg, args...) } // Emit the message and args at INFO level func (z *intLogger) Info(msg string, args ...interface{}) { z.Log(Info, msg, args...) } // Emit the message and args at WARN level func (z *intLogger) Warn(msg string, args ...interface{}) { z.Log(Warn, msg, args...) } // Emit the message and args at ERROR level func (z *intLogger) Error(msg string, args ...interface{}) { z.Log(Error, msg, args...) } // Indicate that the logger would emit TRACE level logs func (z *intLogger) IsTrace() bool { return z.level == Trace } // Indicate that the logger would emit DEBUG level logs func (z *intLogger) IsDebug() bool { return z.level <= Debug } // Indicate that the logger would emit INFO level logs func (z *intLogger) IsInfo() bool { return z.level <= Info } // Indicate that the logger would emit WARN level logs func (z *intLogger) IsWarn() bool { return z.level <= Warn } // Indicate that the logger would emit ERROR level logs func (z *intLogger) IsError() bool { return z.level <= Error } // Return a sub-Logger for which every emitted log message will contain // the given key/value pairs. This is used to create a context specific // Logger. func (z *intLogger) With(args ...interface{}) Logger { var nz intLogger = *z nz.implied = append(nz.implied, args...) return &nz } // Create a new sub-Logger that a name decending from the current name. // This is used to create a subsystem specific Logger. func (z *intLogger) Named(name string) Logger { var nz intLogger = *z if nz.name != "" { nz.name = nz.name + "." + name } else { nz.name = name } return &nz } // Create a new sub-Logger with an explicit name. This ignores the current // name. This is used to create a standalone logger that doesn't fall // within the normal hierarchy. func (z *intLogger) ResetNamed(name string) Logger { var nz intLogger = *z nz.name = name return &nz } // Create a *log.Logger that will send it's data through this Logger. This // allows packages that expect to be using the standard library log to actually // use this logger. func (z *intLogger) StandardLogger(opts *StandardLoggerOptions) *log.Logger { if opts == nil { opts = &StandardLoggerOptions{} } return log.New(&stdlogAdapter{z, opts.InferLevels}, "", 0) }