build: add prefixed logger

build/prefix_log.go

@@ -0,0 +1,112 @@
+package build
+
+import "github.com/btcsuite/btclog"
+
+// PrefixLog is a pass-through logger that adds a prefix to every logged line.
+type PrefixLog struct {
+	log    btclog.Logger
+	prefix string
+}
+
+// NewPrefixLog instantiates a new prefixed logger.
+func NewPrefixLog(prefix string, log btclog.Logger) *PrefixLog {
+	return &PrefixLog{
+		prefix: prefix,
+		log:    log,
+	}
+}
+
+// addFormatPrefix prepends the prefix to a format string.
+func (p *PrefixLog) addFormatPrefix(s string) string {
+	return p.prefix + " " + s
+}
+
+// addArgsPrefix prepends the prefix to a list of arguments.
+func (p *PrefixLog) addArgsPrefix(args []interface{}) []interface{} {
+	return append([]interface{}{p.prefix}, args...)
+}
+
+// Tracef formats message according to format specifier and writes to to log
+// with LevelTrace.
+func (p *PrefixLog) Tracef(format string, params ...interface{}) {
+	p.log.Tracef(p.addFormatPrefix(format), params...)
+}
+
+// Debugf formats message according to format specifier and writes to log with
+// LevelDebug.
+func (p *PrefixLog) Debugf(format string, params ...interface{}) {
+	p.log.Debugf(p.addFormatPrefix(format), params...)
+}
+
+// Infof formats message according to format specifier and writes to log with
+// LevelInfo.
+func (p *PrefixLog) Infof(format string, params ...interface{}) {
+	p.log.Infof(p.addFormatPrefix(format), params...)
+}
+
+// Warnf formats message according to format specifier and writes to to log with
+// LevelWarn.
+func (p *PrefixLog) Warnf(format string, params ...interface{}) {
+	p.log.Warnf(p.addFormatPrefix(format), params...)
+}
+
+// Errorf formats message according to format specifier and writes to to log
+// with LevelError.
+func (p *PrefixLog) Errorf(format string, params ...interface{}) {
+	p.log.Errorf(p.addFormatPrefix(format), params...)
+}
+
+// Criticalf formats message according to format specifier and writes to log
+// with LevelCritical.
+func (p *PrefixLog) Criticalf(format string, params ...interface{}) {
+	p.log.Criticalf(p.addFormatPrefix(format), params...)
+}
+
+// Trace formats message using the default formats for its operands and writes
+// to log with LevelTrace.
+func (p *PrefixLog) Trace(v ...interface{}) {
+	p.log.Trace(p.addArgsPrefix(v)...)
+}
+
+// Debug formats message using the default formats for its operands and writes
+// to log with LevelDebug.
+func (p *PrefixLog) Debug(v ...interface{}) {
+	p.log.Debug(p.addArgsPrefix(v)...)
+}
+
+// Info formats message using the default formats for its operands and writes to
+// log with LevelInfo.
+func (p *PrefixLog) Info(v ...interface{}) {
+	p.log.Info(p.addArgsPrefix(v)...)
+}
+
+// Warn formats message using the default formats for its operands and writes to
+// log with LevelWarn.
+func (p *PrefixLog) Warn(v ...interface{}) {
+	p.log.Warn(p.addArgsPrefix(v)...)
+}
+
+// Error formats message using the default formats for its operands and writes
+// to log with LevelError.
+func (p *PrefixLog) Error(v ...interface{}) {
+	p.log.Error(p.addArgsPrefix(v)...)
+}
+
+// Critical formats message using the default formats for its operands and
+// writes to log with LevelCritical.
+func (p *PrefixLog) Critical(v ...interface{}) {
+	p.log.Critical(p.addArgsPrefix(v)...)
+}
+
+// Level returns the current logging level.
+func (p *PrefixLog) Level() btclog.Level {
+	return p.log.Level()
+}
+
+// SetLevel changes the logging level to the passed level.
+func (p *PrefixLog) SetLevel(level btclog.Level) {
+	p.log.SetLevel(level)
+}
+
+// Assert that PrefixLog fulfills the btclog.Logger interface.
+var _ btclog.Logger = &PrefixLog{}