Documentation ¶
Overview ¶
Package glog implements logging analogous to the Google-internal C++ INFO/ERROR/V setup. It provides functions Info, Warning, Error, Fatal, plus formatting variants such as Infof. It also provides V-style logging controlled by the -v and -vmodule=file=2 flags.
Basic examples:
glog.Info("Prepare to repel boarders") glog.Fatalf("Initialization failed: %s", err)
See the documentation for the V function for an explanation of these examples:
if glog.V(2) { glog.Info("Starting transaction...") } glog.V(2).Infoln("Processed", nItems, "elements")
Log output is buffered and written periodically using Flush. Programs should call Flush before exiting to guarantee all log output is written.
By default, all log statements write to files in a temporary directory. This package provides several flags that modify this behavior. As a result, flag.Parse must be called before any logging is done.
-logtostderr=false Logs are written to standard error instead of to files. -alsologtostderr=false Logs are written to standard error as well as to files. -stderrthreshold=ERROR Log events at or above this severity are logged to standard error as well as to files. -log_dir="" Log files will be written to this directory instead of the default temporary directory. Other flags provide aids to debugging. -log_backtrace_at="" When set to a file and line number holding a logging statement, such as -log_backtrace_at=gopherflakes.go:234 a stack trace will be written to the Info log whenever execution hits that statement. (Unlike with -vmodule, the ".go" must be present.) -v=0 Enable V-leveled logging at the specified level. -vmodule="" The syntax of the argument is a comma-separated list of pattern=N, where pattern is a literal file name (minus the ".go" suffix) or "glob" pattern and N is a V level. For instance, -vmodule=gopher*=3 sets the V level to 3 in all Go files whose names begin "gopher".
Index ¶
- Variables
- func CopyStandardLogTo(name string)
- func DebugDepth(depth int, args ...interface{})
- func ErrorDepth(depth int, args ...interface{})
- func Exit(args ...interface{})
- func ExitDepth(depth int, args ...interface{})
- func Exitf(format string, args ...interface{})
- func Exitln(args ...interface{})
- func Fatal(args ...interface{})
- func FatalDepth(depth int, args ...interface{})
- func Fatalf(format string, args ...interface{})
- func Fatalln(args ...interface{})
- func Flush()
- func InfoDepth(depth int, args ...interface{})
- func Init(options Options)
- func NewTextFormatter(l *loggingT) *textFormatter
- func NewdefaultFormatter(l *loggingT) *defaultFormatter
- func SetFormatter(f Formatter)
- func SetHeaderFlag(b bool)
- func SetLogDir(dir *string)
- func SetTextFormatter()
- func ShowLoggingInfo()
- func VLOG(v Level, args ...interface{})
- func VLOGF(v Level, format string, args ...interface{})
- func VLOGLN(v Level, args ...interface{})
- func WarningDepth(depth int, args ...interface{})
- type Formatter
- type Level
- type Options
- type OutputStats
- type Verbose
Constants ¶
This section is empty.
Variables ¶
var ( Debug logNormal = glogEmpty Info logNormal = glogEmpty Warning logNormal = glogEmpty Error logNormal = glogError )
Debug logs to DEBUG log Arguments are handled in the manner of fmt.Print; a newline is appended if missing.
var ( Debugf logFormat = glogEmptyf Infof logFormat = glogEmptyf Warningf logFormat = glogEmptyf Errorf logFormat = glogErrorf )
var ( Debugln logNormalln = glogEmptyln Infoln logNormalln = glogEmptyln Warningln logNormalln = glogEmptyln Errorln logNormalln = glogErrorln )
var MaxSize uint64 = 1024 * 1024 * 1800
MaxSize is the maximum size of a log file in bytes.
var Stats struct { Debug, Info, Warning, Error OutputStats }
Stats tracks the number of lines of output and number of bytes per severity level. Values must be read with atomic.LoadInt64.
Functions ¶
func CopyStandardLogTo ¶
func CopyStandardLogTo(name string)
CopyStandardLogTo arranges for messages written to the Go "log" package's default logs to also appear in the Google logs for the named and lower severities. Subsequent changes to the standard log's default output location or format may break this behavior.
Valid names are "INFO", "WARNING", "ERROR", and "FATAL". If the name is not recognized, CopyStandardLogTo panics.
func DebugDepth ¶
func DebugDepth(depth int, args ...interface{})
DebugDepth acts as Info but uses depth to determine which call frame to log. DebugDepth(0, "msg") is the same as Info("msg").
func ErrorDepth ¶
func ErrorDepth(depth int, args ...interface{})
ErrorDepth acts as Error but uses depth to determine which call frame to log. ErrorDepth(0, "msg") is the same as Error("msg").
func Exit ¶
func Exit(args ...interface{})
Exit logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1). Arguments are handled in the manner of fmt.Print; a newline is appended if missing.
func ExitDepth ¶
func ExitDepth(depth int, args ...interface{})
ExitDepth acts as Exit but uses depth to determine which call frame to log. ExitDepth(0, "msg") is the same as Exit("msg").
func Exitf ¶
func Exitf(format string, args ...interface{})
Exitf logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1). Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.
func Exitln ¶
func Exitln(args ...interface{})
Exitln logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1).
func Fatal ¶
func Fatal(args ...interface{})
Fatal logs to the FATAL, ERROR, WARNING, and INFO logs, including a stack trace of all running goroutines, then calls os.Exit(255). Arguments are handled in the manner of fmt.Print; a newline is appended if missing.
func FatalDepth ¶
func FatalDepth(depth int, args ...interface{})
FatalDepth acts as Fatal but uses depth to determine which call frame to log. FatalDepth(0, "msg") is the same as Fatal("msg").
func Fatalf ¶
func Fatalf(format string, args ...interface{})
Fatalf logs to the FATAL, ERROR, WARNING, and INFO logs, including a stack trace of all running goroutines, then calls os.Exit(255). Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.
func Fatalln ¶
func Fatalln(args ...interface{})
Fatalln logs to the FATAL, ERROR, WARNING, and INFO logs, including a stack trace of all running goroutines, then calls os.Exit(255). Arguments are handled in the manner of fmt.Println; a newline is appended if missing.
func InfoDepth ¶
func InfoDepth(depth int, args ...interface{})
InfoDepth acts as Info but uses depth to determine which call frame to log. InfoDepth(0, "msg") is the same as Info("msg").
func NewTextFormatter ¶
func NewTextFormatter(l *loggingT) *textFormatter
func NewdefaultFormatter ¶
func NewdefaultFormatter(l *loggingT) *defaultFormatter
func SetFormatter ¶
func SetFormatter(f Formatter)
func SetHeaderFlag ¶
func SetHeaderFlag(b bool)
func SetTextFormatter ¶
func SetTextFormatter()
func ShowLoggingInfo ¶
func ShowLoggingInfo()
func WarningDepth ¶
func WarningDepth(depth int, args ...interface{})
WarningDepth acts as Warning but uses depth to determine which call frame to log. WarningDepth(0, "msg") is the same as Warning("msg").
Types ¶
type Level ¶
type Level int32
Level specifies a level of verbosity for V logs. *Level implements flag.Value; the -v flag is of type Level and should be modified only through the flag.Value interface.
type OutputStats ¶
type OutputStats struct {
// contains filtered or unexported fields
}
OutputStats tracks the number of output lines and bytes written.
func (*OutputStats) Bytes ¶
func (s *OutputStats) Bytes() int64
Bytes returns the number of bytes written.
func (*OutputStats) Lines ¶
func (s *OutputStats) Lines() int64
Lines returns the number of lines written.
type Verbose ¶
type Verbose bool
Verbose is a boolean type that implements Infof (like Printf) etc. See the documentation of V for more information.
func V ¶
V reports whether verbosity at the call site is at least the requested level. The returned value is a boolean of type Verbose, which implements Info, Infoln and Infof. These methods will write to the Info log if called. Thus, one may write either
if glog.V(2) { glog.Info("log this") }
or
glog.V(2).Info("log this")
The second form is shorter but the first is cheaper if logging is off because it does not evaluate its arguments.
Whether an individual call to V generates a log record depends on the setting of the -v and --vmodule flags; both are off by default. If the level in the call to V is at least the value of -v, or of -vmodule for the source file containing the call, the V call will log.
func (Verbose) Debug ¶
func (v Verbose) Debug(args ...interface{})
Debug is equivalent to the global Debug function, guarded by the value of v. See the documentation of V for usage.
func (Verbose) Debugf ¶
Debugf is equivalent to the global Debugf function, guarded by the value of v. See the documentation of V for usage.
func (Verbose) Debugln ¶
func (v Verbose) Debugln(args ...interface{})
Debugln is equivalent to the global Debugln function, guarded by the value of v. See the documentation of V for usage.
func (Verbose) Info ¶
func (v Verbose) Info(args ...interface{})
Info is equivalent to the global Info function, guarded by the value of v. See the documentation of V for usage.