63 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
package log
 | 
						|
 | 
						|
import (
 | 
						|
	"time"
 | 
						|
 | 
						|
	"github.com/go-stack/stack"
 | 
						|
)
 | 
						|
 | 
						|
// A Valuer generates a log value. When passed to Context.With in a value
 | 
						|
// element (odd indexes), it represents a dynamic value which is re-evaluated
 | 
						|
// with each log event.
 | 
						|
type Valuer func() interface{}
 | 
						|
 | 
						|
// bindValues replaces all value elements (odd indexes) containing a Valuer
 | 
						|
// with their generated value.
 | 
						|
func bindValues(keyvals []interface{}) {
 | 
						|
	for i := 1; i < len(keyvals); i += 2 {
 | 
						|
		if v, ok := keyvals[i].(Valuer); ok {
 | 
						|
			keyvals[i] = v()
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// containsValuer returns true if any of the value elements (odd indexes)
 | 
						|
// contain a Valuer.
 | 
						|
func containsValuer(keyvals []interface{}) bool {
 | 
						|
	for i := 1; i < len(keyvals); i += 2 {
 | 
						|
		if _, ok := keyvals[i].(Valuer); ok {
 | 
						|
			return true
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return false
 | 
						|
}
 | 
						|
 | 
						|
// Timestamp returns a Valuer that invokes the underlying function when bound,
 | 
						|
// returning a time.Time. Users will probably want to use DefaultTimestamp or
 | 
						|
// DefaultTimestampUTC.
 | 
						|
func Timestamp(t func() time.Time) Valuer {
 | 
						|
	return func() interface{} { return t() }
 | 
						|
}
 | 
						|
 | 
						|
var (
 | 
						|
	// DefaultTimestamp is a Valuer that returns the current wallclock time,
 | 
						|
	// respecting time zones, when bound.
 | 
						|
	DefaultTimestamp Valuer = func() interface{} { return time.Now().Format(time.RFC3339) }
 | 
						|
 | 
						|
	// DefaultTimestampUTC is a Valuer that returns the current time in UTC
 | 
						|
	// when bound.
 | 
						|
	DefaultTimestampUTC Valuer = func() interface{} { return time.Now().UTC().Format(time.RFC3339) }
 | 
						|
)
 | 
						|
 | 
						|
// Caller returns a Valuer that returns a file and line from a specified depth
 | 
						|
// in the callstack. Users will probably want to use DefaultCaller.
 | 
						|
func Caller(depth int) Valuer {
 | 
						|
	return func() interface{} { return stack.Caller(depth) }
 | 
						|
}
 | 
						|
 | 
						|
var (
 | 
						|
	// DefaultCaller is a Valuer that returns the file and line where the Log
 | 
						|
	// method was invoked. It can only be used with log.With.
 | 
						|
	DefaultCaller = Caller(3)
 | 
						|
)
 |