logger

Documentation

Index

• Constants
• Variables
• func ContextLog(ctx Valuer, err []error, entry *logrus.Entry) *logrus.Entry
• func GetLoggableValue(ctx Valuer, key string) interface{}
• func GetLoggableValues(ctx Valuer) logrus.Fields
• func LogIfError(ctx context.Context, fn func() error, logger Logger, msg string)
• func WatchingLoggable(ctx context.Context, l Loggable) context.Context
• func WithField(ctx context.Context, k string, v interface{}) context.Context
• func WithFields(ctx context.Context, m logrus.Fields) context.Context
• func WithLoggable(ctx context.Context, l Loggable) context.Context
• func WithUUID(ctx context.Context) (context.Context, string)
• type Loggable
• type Logger
  • func New(name string) Logger
• type Valuer

Examples

• WatchingLoggable
• WithField
• WithFields

Constants

const UUIDKey = "uuid"

Variables

var GlobalFields = logrus.Fields{}

Functions

func ContextLog

func ContextLog(ctx Valuer, err []error, entry *logrus.Entry) *logrus.Entry

func GetLoggableValue

func GetLoggableValue(ctx Valuer, key string) interface{}

GetLoggableValue returns the value of the metadata currently attached to the Context.

func GetLoggableValues

func GetLoggableValues(ctx Valuer) logrus.Fields

func LogIfError

func LogIfError(ctx context.Context, fn func() error, logger Logger, msg string)

LogIfError makes it less verbose to defer a Close() call while handling an unlikely-but-possible error return by logging it. Example:

defer LogIfError(ctx, f.Close, log, "failed to close file")

func WatchingLoggable

func WatchingLoggable(ctx context.Context, l Loggable) context.Context

WatchingLoggable attaches a Loggable to the Context. Upon logging, LogFields will be called and the fields will be attached as metadata.

Example

loggable := &exampleLoggable{"foo": "bar"}

ctx := context.Background()
ctx = WatchingLoggable(ctx, loggable)

log := New("testing")

// Typically called as log(ctx, nil).Debug("the message")
entry := log(ctx, nil)
fmt.Printf("%+v", entry.Data["foo"])

Output:

bar

func WithField

func WithField(ctx context.Context, k string, v interface{}) context.Context

WithField attaches a key-value pair to a Context. Upon logging, the pair will be attached as metadata.

Example

ctx := context.Background()
ctx = WithField(ctx, "foo", "bar")

log := New("testing")

// Typically called as log(ctx, nil).Debug("the message")
entry := log(ctx, nil)
fmt.Printf("%+v", entry.Data["foo"])

Output:

bar

func WithFields

func WithFields(ctx context.Context, m logrus.Fields) context.Context

WithFields attaches fields to a Context. Upon logging, those fields will be attached as metadata.

Example

ctx := context.Background()
ctx = WithFields(ctx, logrus.Fields{
	"foo": "bar",
})

log := New("testing")

// Typically called as log(ctx, nil).Debug("the message")
entry := log(ctx, nil)
fmt.Printf("%+v", entry.Data["foo"])

Output:

bar

func WithLoggable

func WithLoggable(ctx context.Context, l Loggable) context.Context

WithLoggable attaches a Loggable's fields to the Context. Upon logging, those fields will be attached as metadata.

func WithUUID

func WithUUID(ctx context.Context) (context.Context, string)

Types

type Loggable

type Loggable interface {
	LogFields() logrus.Fields
}

type Logger

type Logger func(Valuer, ...error) *logrus.Entry

func New

func New(name string) Logger

type Valuer

type Valuer interface {
	Value(key interface{}) interface{}
}

Valuer is essentially a Context, but down-scoped to what Loggable expects