zmlog

zmlog (Zap MarshalLogObject Generator)

zmlog generates the file which has MarshalLogObject method from struct.

Install

go install github.com/muroon/zmlog/cmd/zmlog@latest

How to generate file

For example, there is a file target.go that describes the struct for Log as follows.

type TargetLog struct {
	ID   int
	Name string
	Time time.Time
}

Run the command below,

zmlog -f target.go

And zmlog generates a file target_zap_obj.go with MarshalLogObject method.

// MarshalLogObject zapcore.ObjectMarshaler interface method
func (l *TargetLog) MarshalLogObject(enc zapcore.ObjectEncoder) error {
		var err error
		enc.AddInt("id", l.ID)
		enc.AddString("name", l.Name)
		enc.AddTime("time", l.Time)
		return err	
}

Key

The key name for zapcore.ObjectEncoder's method like AddInt or AddString... is basically the field name of the target struct with snake case. However, as an exception, create a tag with key: "key name" in the field of the struct.

In the example below, it is originally enc.AddString("sessison_id", l.SessionID), but it becomes enc.AddString("sess_id", l.SessionID)

type TargetLog struct {
	ID        int
	Name      string
	Time      time.Time
	SessionID string `key:"sess_id"` // custom key
}

func (l *TargetLog) MarshalLogObject(enc zapcore.ObjectEncoder) error {
		var err error
		enc.AddInt("id", l.ID)
		enc.AddString("name", l.Name)
		enc.AddTime("time", l.Time)
		enc.AddString("sess_id", l.SessionID) // not be `sessison_id`
		return err	
}