distribution/vendor/github.com/anacrolix/log/logger-core.go

126 lines
3.2 KiB
Go

package log
import (
"fmt"
"path/filepath"
)
// loggerCore is the essential part of Logger.
type loggerCore struct {
nonZero bool
names []string
values []interface{}
// Propagate on NOTSET?
defaultLevel Level
// Use propagation on NOTSET.
filterLevel Level
msgMaps []func(Msg) Msg
Handlers []Handler
}
func (l loggerCore) asLogger() Logger {
return Logger{l}
}
// Returns a logger that adds the given values to logged messages.
func (l loggerCore) WithValues(v ...interface{}) Logger {
l.values = append(l.values, v...)
return l.asLogger()
}
// Returns a logger that for a given message propagates the result of `f` instead.
func (l loggerCore) WithMap(f func(m Msg) Msg) Logger {
l.msgMaps = append(l.msgMaps, f)
return l.asLogger()
}
func (l loggerCore) WithDefaultLevel(level Level) Logger {
l.defaultLevel = level
return l.asLogger()
}
func (l loggerCore) WithFilterLevel(minLevel Level) Logger {
l.filterLevel = minLevel
return l.asLogger()
}
// Deprecated. Use WithFilterLevel. This method name is misleading and doesn't follow the convention
// elsewhere.
func (l loggerCore) FilterLevel(minLevel Level) Logger {
return l.WithFilterLevel(minLevel)
}
func (l loggerCore) IsZero() bool {
return !l.nonZero
}
// Deprecated. This should require a msg, since filtering includes the location a msg is created at.
// That would require building a message before we can do checks, which means lazily constructing
// the message but not the caller location.
func (l loggerCore) IsEnabledFor(level Level) bool {
// TODO: Take a message?
return true
}
func (l loggerCore) LazyLog(level Level, f func() Msg) {
l.lazyLog(level, 1, f)
}
func (l loggerCore) LazyLogDefaultLevel(f func() Msg) {
l.lazyLog(NotSet, 1, f)
}
func (l loggerCore) lazyLog(level Level, skip int, f func() Msg) {
if level.isNotSet() {
level = l.defaultLevel
}
r := f().Skip(skip + 1)
msgLoc := getMsgLogLoc(r)
names := append(
l.names[:len(l.names):len(l.names)],
msgLoc.Package,
fmt.Sprintf("%v:%v", filepath.Base(msgLoc.File), msgLoc.Line),
)
if rulesLevel, ok := levelFromRules(names); ok {
if level.LessThan(rulesLevel) {
return
}
} else if level.LessThan(l.filterLevel) {
return
}
for i := len(l.msgMaps) - 1; i >= 0; i-- {
r = l.msgMaps[i](r)
}
l.handle(level, r, names)
}
// Goes from an affirmative decision to log, to sending it to the handlers in the right form.
func (l loggerCore) handle(level Level, m Msg, names []string) {
r := Record{
// Do we really need to be passing the full Msg caller context at this point?
Msg: m.Skip(1),
Level: level,
Names: names,
}
if !l.nonZero {
panic(fmt.Sprintf("Logger uninitialized. names=%q", l.names))
}
for _, h := range l.Handlers {
h.Handle(r)
}
}
func (l loggerCore) WithNames(names ...string) Logger {
// Avoid sharing after appending. This might not be enough because some formatters might add
// more elements concurrently, or names could be empty.
l.names = append(l.names[:len(l.names):len(l.names)], names...)
return l.asLogger()
}
// Clobber the Loggers Handlers. Note this breaks convention by not returning a new Logger, but
// seems to fit here.
func (l *loggerCore) SetHandlers(h ...Handler) {
l.Handlers = h
l.nonZero = true
}