package internal import ( "bufio" "bytes" "compress/gzip" "context" "crypto/rand" "errors" "fmt" "io" "math" "math/big" "os" "os/exec" "runtime" "strconv" "strings" "sync" "syscall" "time" "unicode" "github.com/alecthomas/units" ) const alphanum string = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" var ( TimeoutErr = errors.New("Command timed out.") NotImplementedError = errors.New("not implemented yet") VersionAlreadySetError = errors.New("version has already been set") ) // Set via the main module var version string // Duration just wraps time.Duration type Duration struct { Duration time.Duration } // Size just wraps an int64 type Size struct { Size int64 } type Number struct { Value float64 } type ReadWaitCloser struct { pipeReader *io.PipeReader wg sync.WaitGroup } // SetVersion sets the telegraf agent version func SetVersion(v string) error { if version != "" { return VersionAlreadySetError } version = v return nil } // Version returns the telegraf agent version func Version() string { return version } // ProductToken returns a tag for Telegraf that can be used in user agents. func ProductToken() string { return fmt.Sprintf("Telegraf/%s Go/%s", Version(), strings.TrimPrefix(runtime.Version(), "go")) } // UnmarshalTOML parses the duration from the TOML config file func (d *Duration) UnmarshalTOML(b []byte) error { var err error b = bytes.Trim(b, `'`) // see if we can directly convert it d.Duration, err = time.ParseDuration(string(b)) if err == nil { return nil } // Parse string duration, ie, "1s" if uq, err := strconv.Unquote(string(b)); err == nil && len(uq) > 0 { d.Duration, err = time.ParseDuration(uq) if err == nil { return nil } } // First try parsing as integer seconds sI, err := strconv.ParseInt(string(b), 10, 64) if err == nil { d.Duration = time.Second * time.Duration(sI) return nil } // Second try parsing as float seconds sF, err := strconv.ParseFloat(string(b), 64) if err == nil { d.Duration = time.Second * time.Duration(sF) return nil } return nil } func (s *Size) UnmarshalTOML(b []byte) error { var err error b = bytes.Trim(b, `'`) val, err := strconv.ParseInt(string(b), 10, 64) if err == nil { s.Size = val return nil } uq, err := strconv.Unquote(string(b)) if err != nil { return err } val, err = units.ParseStrictBytes(uq) if err != nil { return err } s.Size = val return nil } func (n *Number) UnmarshalTOML(b []byte) error { value, err := strconv.ParseFloat(string(b), 64) if err != nil { return err } n.Value = value return nil } // ReadLines reads contents from a file and splits them by new lines. // A convenience wrapper to ReadLinesOffsetN(filename, 0, -1). func ReadLines(filename string) ([]string, error) { return ReadLinesOffsetN(filename, 0, -1) } // ReadLines reads contents from file and splits them by new line. // The offset tells at which line number to start. // The count determines the number of lines to read (starting from offset): // n >= 0: at most n lines // n < 0: whole file func ReadLinesOffsetN(filename string, offset uint, n int) ([]string, error) { f, err := os.Open(filename) if err != nil { return []string{""}, err } defer f.Close() var ret []string r := bufio.NewReader(f) for i := 0; i < n+int(offset) || n < 0; i++ { line, err := r.ReadString('\n') if err != nil { break } if i < int(offset) { continue } ret = append(ret, strings.Trim(line, "\n")) } return ret, nil } // RandomString returns a random string of alpha-numeric characters func RandomString(n int) string { var bytes = make([]byte, n) rand.Read(bytes) for i, b := range bytes { bytes[i] = alphanum[b%byte(len(alphanum))] } return string(bytes) } // SnakeCase converts the given string to snake case following the Golang format: // acronyms are converted to lower-case and preceded by an underscore. func SnakeCase(in string) string { runes := []rune(in) length := len(runes) var out []rune for i := 0; i < length; i++ { if i > 0 && unicode.IsUpper(runes[i]) && ((i+1 < length && unicode.IsLower(runes[i+1])) || unicode.IsLower(runes[i-1])) { out = append(out, '_') } out = append(out, unicode.ToLower(runes[i])) } return string(out) } // RandomSleep will sleep for a random amount of time up to max. // If the shutdown channel is closed, it will return before it has finished // sleeping. func RandomSleep(max time.Duration, shutdown chan struct{}) { if max == 0 { return } maxSleep := big.NewInt(max.Nanoseconds()) var sleepns int64 if j, err := rand.Int(rand.Reader, maxSleep); err == nil { sleepns = j.Int64() } t := time.NewTimer(time.Nanosecond * time.Duration(sleepns)) select { case <-t.C: return case <-shutdown: t.Stop() return } } // RandomDuration returns a random duration between 0 and max. func RandomDuration(max time.Duration) time.Duration { if max == 0 { return 0 } var sleepns int64 maxSleep := big.NewInt(max.Nanoseconds()) if j, err := rand.Int(rand.Reader, maxSleep); err == nil { sleepns = j.Int64() } return time.Duration(sleepns) } // SleepContext sleeps until the context is closed or the duration is reached. func SleepContext(ctx context.Context, duration time.Duration) error { if duration == 0 { return nil } t := time.NewTimer(duration) select { case <-t.C: return nil case <-ctx.Done(): t.Stop() return ctx.Err() } } // AlignDuration returns the duration until next aligned interval. // If the current time is aligned a 0 duration is returned. func AlignDuration(tm time.Time, interval time.Duration) time.Duration { return AlignTime(tm, interval).Sub(tm) } // AlignTime returns the time of the next aligned interval. // If the current time is aligned the current time is returned. func AlignTime(tm time.Time, interval time.Duration) time.Time { truncated := tm.Truncate(interval) if truncated == tm { return tm } return truncated.Add(interval) } // Exit status takes the error from exec.Command // and returns the exit status and true // if error is not exit status, will return 0 and false func ExitStatus(err error) (int, bool) { if exiterr, ok := err.(*exec.ExitError); ok { if status, ok := exiterr.Sys().(syscall.WaitStatus); ok { return status.ExitStatus(), true } } return 0, false } func (r *ReadWaitCloser) Close() error { err := r.pipeReader.Close() r.wg.Wait() // wait for the gzip goroutine finish return err } // CompressWithGzip takes an io.Reader as input and pipes // it through a gzip.Writer returning an io.Reader containing // the gzipped data. // An error is returned if passing data to the gzip.Writer fails func CompressWithGzip(data io.Reader) (io.ReadCloser, error) { pipeReader, pipeWriter := io.Pipe() gzipWriter := gzip.NewWriter(pipeWriter) rc := &ReadWaitCloser{ pipeReader: pipeReader, } rc.wg.Add(1) var err error go func() { _, err = io.Copy(gzipWriter, data) gzipWriter.Close() // subsequent reads from the read half of the pipe will // return no bytes and the error err, or EOF if err is nil. pipeWriter.CloseWithError(err) rc.wg.Done() }() return pipeReader, err } // ParseTimestamp parses a Time according to the standard Telegraf options. // These are generally displayed in the toml similar to: // json_time_key= "timestamp" // json_time_format = "2006-01-02T15:04:05Z07:00" // json_timezone = "America/Los_Angeles" // // The format can be one of "unix", "unix_ms", "unix_us", "unix_ns", or a Go // time layout suitable for time.Parse. // // When using the "unix" format, a optional fractional component is allowed. // Specific unix time precisions cannot have a fractional component. // // Unix times may be an int64, float64, or string. When using a Go format // string the timestamp must be a string. // // The location is a location string suitable for time.LoadLocation. Unix // times do not use the location string, a unix time is always return in the // UTC location. func ParseTimestamp(format string, timestamp interface{}, location string) (time.Time, error) { switch format { case "unix", "unix_ms", "unix_us", "unix_ns": return parseUnix(format, timestamp) default: if location == "" { location = "UTC" } return parseTime(format, timestamp, location) } } func parseUnix(format string, timestamp interface{}) (time.Time, error) { integer, fractional, err := parseComponents(timestamp) if err != nil { return time.Unix(0, 0), err } switch strings.ToLower(format) { case "unix": return time.Unix(integer, fractional).UTC(), nil case "unix_ms": return time.Unix(0, integer*1e6).UTC(), nil case "unix_us": return time.Unix(0, integer*1e3).UTC(), nil case "unix_ns": return time.Unix(0, integer).UTC(), nil default: return time.Unix(0, 0), errors.New("unsupported type") } } // Returns the integers before and after an optional decimal point. Both '.' // and ',' are supported for the decimal point. The timestamp can be an int64, // float64, or string. // ex: "42.5" -> (42, 5, nil) func parseComponents(timestamp interface{}) (int64, int64, error) { switch ts := timestamp.(type) { case string: parts := strings.SplitN(ts, ".", 2) if len(parts) == 2 { return parseUnixTimeComponents(parts[0], parts[1]) } parts = strings.SplitN(ts, ",", 2) if len(parts) == 2 { return parseUnixTimeComponents(parts[0], parts[1]) } integer, err := strconv.ParseInt(ts, 10, 64) if err != nil { return 0, 0, err } return integer, 0, nil case int64: return ts, 0, nil case float64: integer, fractional := math.Modf(ts) return int64(integer), int64(fractional * 1e9), nil default: return 0, 0, errors.New("unsupported type") } } func parseUnixTimeComponents(first, second string) (int64, int64, error) { integer, err := strconv.ParseInt(first, 10, 64) if err != nil { return 0, 0, err } // Convert to nanoseconds, dropping any greater precision. buf := []byte("000000000") copy(buf, second) fractional, err := strconv.ParseInt(string(buf), 10, 64) if err != nil { return 0, 0, err } return integer, fractional, nil } // ParseTime parses a string timestamp according to the format string. func parseTime(format string, timestamp interface{}, location string) (time.Time, error) { switch ts := timestamp.(type) { case string: loc, err := time.LoadLocation(location) if err != nil { return time.Unix(0, 0), err } return time.ParseInLocation(format, ts, loc) default: return time.Unix(0, 0), errors.New("unsupported type") } }