log

type LogType string

type LoggerImpl interface {
	// Enabled tests whether this Logger is enabled.  For example, commandline
	// flags might be used to set the logging verbosity and disable some info
	// logs.
	Enabled() bool

	// Info logs a non-error message with the given key/value pairs as context.
	//
	// The msg argument should be used to add some constant description to
	// the log line.  The key/value pairs can then be used to add additional
	// variable information.  The key/value pairs should alternate string
	// keys and arbitrary values.
	Info(msg string, keysAndValues ...interface{})

	// Error logs an error, with the given message and key/value pairs as context.
	// It functions similarly to calling Info with the "error" named value, but may
	// have unique behavior, and should be preferred for logging errors (see the
	// package documentations for more information).
	//
	// The msg field should be used to add context to any underlying error,
	// while the err field should be used to attach the actual error that
	// triggered this log line, if present.
	Error(err error, msg string, keysAndValues ...interface{})

	// V returns an Logger value for a specific verbosity level, relative to
	// this Logger.  In other words, V values are additive.  V higher verbosity
	// level means a log message is less important.  It's illegal to pass a log
	// level less than zero.
	V(level int) LoggerImpl

	// WithValues adds some key-value pairs of context to a logger.
	// See Info for documentation on how key/value pairs work.
	WithValues(keysAndValues ...interface{}) LoggerImpl

	// WithName adds a new element to the logger's name.
	// Successive calls with WithName continue to append
	// suffixes to the logger's name.  It's strongly recommended
	// that name segments contain only letters, digits, and hyphens
	// (see the package documentation for more information).
	WithName(name string) LoggerImpl

	// Infof logs a non-error messages with the given message format with format specifier and arguments.
	Infof(format string, args ...interface{})
	// Errorf logs a error message with the given key/value pairs as context.
	Errorf(format string, args ...interface{})
	// Warning logs a warning messages with the given key/value pairs as context.
	Warning(msg string, kvs ...interface{})
	// Warningf logs a warning messages with the given message format with format specifier and arguments.
	Warningf(format string, args ...interface{})
	// Success logs a success messages with the given key/value pairs as context.
	Success(msg string, kvs ...interface{})
	// Successf logs a success messages with the given message format with format specifier and arguments.
	Successf(format string, args ...interface{})
	// Fatal logs a fatal message with the given key/value pairs as context and returns with os.Exit(1)
	Fatal(err error, msg string, kvs ...interface{})
	// Print logs a message of generic type
	Print(msg string, err error, logType string, kvs ...interface{})
	// Output writes a message to stdout
	Outputf(msg string, kvs ...interface{})
	// SetThreshold implements a New Option that allows to set the threshold level for a logger.
	// The logger will write only log messages with a level/V(x) equal or higher to the threshold.
	SetThreshold(threshold *int32)
	// Clone creates cloned copy of the logger
	Clone() LoggerImpl
	// CloneWithLevel creates cloned copy of the logger with updated log level
	CloneWithLevel(level int) LoggerImpl
	// WithCallDepth implements a New Option that allows to set the callDepth level for a logger.
	WithCallDepth(callDepth int) LoggerImpl
}

type Writer interface {

	// Write writes message to stdout/stderr, logfile and sends to the channel if channel is set
	//
	// header is message header to append as a message prefix
	// msg is actual message to write
	// logEnabled is used to decide whether to write this message to stdout/stderr or not
	// logVerbosity is used to decide which message to write for different output types
	// logType used to decide should write to stdout or stderr
	Write(header []byte, msg []byte, logEnabled bool, logVerbosity int32, logType string) (n int, err error)

	// SetFile sets the logFile to writer
	// if the non-empty file name is used, writer will also
	// write the logs to this file
	SetFile(fileName string)

	// SetAuditLog sets the log file that should capture all logging activity. This
	// file will contain all logging regardless of set verbosity level.
	SetAuditLog(fileName string)

	// QuietMode sets the logging mode to quiet
	// If this mode is set, writer will not write anything to stderr
	QuietMode(quiet bool)

	// ShowTimestamp shows timestamp along with log
	ShowTimestamp(show bool)

	// SetVerbosity sets verbosity level and also updates default verbosity level
	SetVerbosity(verbosity int32)

	// SetStdout overrides stdout
	SetStdout(w io.Writer)

	// SetStderr overrides stderr
	SetStderr(w io.Writer)
}