elog

README

Event Logger

This package provides a simple interface for event logging to generic backends as well as a solid set of backend implementations.

Available Storage Backends

• csv: logging events in CSV format, easy for development and log collection
• bq: logging to Google BigQuery, great for production
• gsheets: logging to a Google Sheet, great for low-volume production

Backend Decorators

• async: a decorator to make logging asynchronous
• row: a decorator to make logging to row based backends easier

Installation

go install github.com/trichner/elog

Usage

package main

import (
	"github.com/trichner/elog"
	"github.com/trichner/elog/csv"
	"os"
	"time"
)

func main() {

	// create a new logger with the CSV backend
	logger, err := csv.NewCsvEventLogger(os.Stdout)
	if err != nil {
		panic(err)
	}

	// create a new event
	event := elog.NewEventBuilder().
		WithKind("user_login").
		WithTimeStamp(time.Now()).
		WithPayload(map[string]string{
			"user":   "Alice",
			"remote": "42.0.4.23",
		}).
		Build()

	// ... and log it!
	logger.Log(event)
}

Documentation

Index

• type Event
• type EventBuilder
  • func NewEventBuilder() EventBuilder
• type EventLogger
  • func NewNoOpEventLogger() EventLogger

Examples

• EventLogger

Types

type Event

type Event struct {
	ID        string
	Kind      string
	SessionID string
	Timestamp time.Time
	Payload   any
}

type EventBuilder

type EventBuilder interface {
	WithID(id string) EventBuilder
	WithKind(kind string) EventBuilder
	WithSessionID(session string) EventBuilder
	WithTimeStamp(ts time.Time) EventBuilder
	WithPayload(payload any) EventBuilder

	Build() *Event
}

EventBuilder helps to assemble events. The builder will create a universally unique ID (UUID) for the event ID if none is provided. Furthermore, the Timestamp will be set to 'now' in case it was not provided.

func NewEventBuilder

func NewEventBuilder() EventBuilder

type EventLogger

type EventLogger interface {
	Log(e *Event) error
}

Example

package main

import (
	"github.com/trichner/elog"
	"github.com/trichner/elog/csv"
	"os"
	"time"
)

func main() {

	// create a new logger with the CSV backend
	logger, err := csv.NewCsvEventLogger(os.Stdout)
	if err != nil {
		panic(err)
	}

	event := elog.NewEventBuilder().
		WithKind("user_login").
		WithTimeStamp(time.Now()).
		WithPayload(map[string]string{
			"user":   "Alice",
			"remote": "42.0.4.23",
		}).
		Build()

	logger.Log(event)
}

func NewNoOpEventLogger

func NewNoOpEventLogger() EventLogger