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authorRaúl Benencia <raul@thousandeyes.com>2018-04-13 16:30:31 -0700
committerRaúl Benencia <raul@thousandeyes.com>2018-05-11 15:02:34 -0700
commit77c172b823b64ebface655681ab0749b9d2f7081 (patch)
tree09c13e626eb95ae1d33e76ed683172eab1ab6c96 /vendor/github.com/go-kit/kit/log/level/level.go
First public commit
Diffstat (limited to 'vendor/github.com/go-kit/kit/log/level/level.go')
-rw-r--r--vendor/github.com/go-kit/kit/log/level/level.go205
1 files changed, 205 insertions, 0 deletions
diff --git a/vendor/github.com/go-kit/kit/log/level/level.go b/vendor/github.com/go-kit/kit/log/level/level.go
new file mode 100644
index 0000000..dd4ef60
--- /dev/null
+++ b/vendor/github.com/go-kit/kit/log/level/level.go
@@ -0,0 +1,205 @@
+package level
+
+import "github.com/go-kit/kit/log"
+
+// Error returns a logger that includes a Key/ErrorValue pair.
+func Error(logger log.Logger) log.Logger {
+ return log.WithPrefix(logger, Key(), ErrorValue())
+}
+
+// Warn returns a logger that includes a Key/WarnValue pair.
+func Warn(logger log.Logger) log.Logger {
+ return log.WithPrefix(logger, Key(), WarnValue())
+}
+
+// Info returns a logger that includes a Key/InfoValue pair.
+func Info(logger log.Logger) log.Logger {
+ return log.WithPrefix(logger, Key(), InfoValue())
+}
+
+// Debug returns a logger that includes a Key/DebugValue pair.
+func Debug(logger log.Logger) log.Logger {
+ return log.WithPrefix(logger, Key(), DebugValue())
+}
+
+// NewFilter wraps next and implements level filtering. See the commentary on
+// the Option functions for a detailed description of how to configure levels.
+// If no options are provided, all leveled log events created with Debug,
+// Info, Warn or Error helper methods are squelched and non-leveled log
+// events are passed to next unmodified.
+func NewFilter(next log.Logger, options ...Option) log.Logger {
+ l := &logger{
+ next: next,
+ }
+ for _, option := range options {
+ option(l)
+ }
+ return l
+}
+
+type logger struct {
+ next log.Logger
+ allowed level
+ squelchNoLevel bool
+ errNotAllowed error
+ errNoLevel error
+}
+
+func (l *logger) Log(keyvals ...interface{}) error {
+ var hasLevel, levelAllowed bool
+ for i := 1; i < len(keyvals); i += 2 {
+ if v, ok := keyvals[i].(*levelValue); ok {
+ hasLevel = true
+ levelAllowed = l.allowed&v.level != 0
+ break
+ }
+ }
+ if !hasLevel && l.squelchNoLevel {
+ return l.errNoLevel
+ }
+ if hasLevel && !levelAllowed {
+ return l.errNotAllowed
+ }
+ return l.next.Log(keyvals...)
+}
+
+// Option sets a parameter for the leveled logger.
+type Option func(*logger)
+
+// AllowAll is an alias for AllowDebug.
+func AllowAll() Option {
+ return AllowDebug()
+}
+
+// AllowDebug allows error, warn, info and debug level log events to pass.
+func AllowDebug() Option {
+ return allowed(levelError | levelWarn | levelInfo | levelDebug)
+}
+
+// AllowInfo allows error, warn and info level log events to pass.
+func AllowInfo() Option {
+ return allowed(levelError | levelWarn | levelInfo)
+}
+
+// AllowWarn allows error and warn level log events to pass.
+func AllowWarn() Option {
+ return allowed(levelError | levelWarn)
+}
+
+// AllowError allows only error level log events to pass.
+func AllowError() Option {
+ return allowed(levelError)
+}
+
+// AllowNone allows no leveled log events to pass.
+func AllowNone() Option {
+ return allowed(0)
+}
+
+func allowed(allowed level) Option {
+ return func(l *logger) { l.allowed = allowed }
+}
+
+// ErrNotAllowed sets the error to return from Log when it squelches a log
+// event disallowed by the configured Allow[Level] option. By default,
+// ErrNotAllowed is nil; in this case the log event is squelched with no
+// error.
+func ErrNotAllowed(err error) Option {
+ return func(l *logger) { l.errNotAllowed = err }
+}
+
+// SquelchNoLevel instructs Log to squelch log events with no level, so that
+// they don't proceed through to the wrapped logger. If SquelchNoLevel is set
+// to true and a log event is squelched in this way, the error value
+// configured with ErrNoLevel is returned to the caller.
+func SquelchNoLevel(squelch bool) Option {
+ return func(l *logger) { l.squelchNoLevel = squelch }
+}
+
+// ErrNoLevel sets the error to return from Log when it squelches a log event
+// with no level. By default, ErrNoLevel is nil; in this case the log event is
+// squelched with no error.
+func ErrNoLevel(err error) Option {
+ return func(l *logger) { l.errNoLevel = err }
+}
+
+// NewInjector wraps next and returns a logger that adds a Key/level pair to
+// the beginning of log events that don't already contain a level. In effect,
+// this gives a default level to logs without a level.
+func NewInjector(next log.Logger, level Value) log.Logger {
+ return &injector{
+ next: next,
+ level: level,
+ }
+}
+
+type injector struct {
+ next log.Logger
+ level interface{}
+}
+
+func (l *injector) Log(keyvals ...interface{}) error {
+ for i := 1; i < len(keyvals); i += 2 {
+ if _, ok := keyvals[i].(*levelValue); ok {
+ return l.next.Log(keyvals...)
+ }
+ }
+ kvs := make([]interface{}, len(keyvals)+2)
+ kvs[0], kvs[1] = key, l.level
+ copy(kvs[2:], keyvals)
+ return l.next.Log(kvs...)
+}
+
+// Value is the interface that each of the canonical level values implement.
+// It contains unexported methods that prevent types from other packages from
+// implementing it and guaranteeing that NewFilter can distinguish the levels
+// defined in this package from all other values.
+type Value interface {
+ String() string
+ levelVal()
+}
+
+// Key returns the unique key added to log events by the loggers in this
+// package.
+func Key() interface{} { return key }
+
+// ErrorValue returns the unique value added to log events by Error.
+func ErrorValue() Value { return errorValue }
+
+// WarnValue returns the unique value added to log events by Warn.
+func WarnValue() Value { return warnValue }
+
+// InfoValue returns the unique value added to log events by Info.
+func InfoValue() Value { return infoValue }
+
+// DebugValue returns the unique value added to log events by Warn.
+func DebugValue() Value { return debugValue }
+
+var (
+ // key is of type interfae{} so that it allocates once during package
+ // initialization and avoids allocating every time the value is added to a
+ // []interface{} later.
+ key interface{} = "level"
+
+ errorValue = &levelValue{level: levelError, name: "error"}
+ warnValue = &levelValue{level: levelWarn, name: "warn"}
+ infoValue = &levelValue{level: levelInfo, name: "info"}
+ debugValue = &levelValue{level: levelDebug, name: "debug"}
+)
+
+type level byte
+
+const (
+ levelDebug level = 1 << iota
+ levelInfo
+ levelWarn
+ levelError
+)
+
+type levelValue struct {
+ name string
+ level
+}
+
+func (v *levelValue) String() string { return v.name }
+func (v *levelValue) levelVal() {}
nihil fit ex nihilo