gin-go-metrics

gin-go-metrics is gin-gonic/gin middleware to gather and store metrics using rcrowley/go-metrics

How to use

gin middleware

package main

import (
	"fmt"
	"os"
	"time"

	metrics "github.com/bmc-toolbox/gin-go-metrics"
	"github.com/bmc-toolbox/gin-go-metrics/middleware"
	"github.com/gin-gonic/gin"
)

func main() {
	// Optional part to send metrics to Graphite,
	// as alternative you can send metrics from
	// rcrowley/go-metrics.DefaultRegistry yourself
	err := metrics.Setup(
		"graphite",  // clientType
		"localhost", // graphite host
		2003,        // graphite port
		"server",    // metrics prefix
		time.Minute, // graphite flushInterval
	)
	if err != nil {
		fmt.Printf("Failed to set up monitoring: %s\n", err)
		os.Exit(1)
	}

	r := gin.New()

	// argument to NewMetrics tells which variables need to be
	// expanded in metrics, more on that by link:
	// https://banzaicloud.com/blog/monitoring-gin-with-prometheus/
	p := middleware.NewMetrics([]string{"expanded_parameter"})
	r.Use(p.HandlerFunc(
		[]string{"/ping", "/api/ping"}, // ignore given URLs from stats
		true,                           // replace "/" with "_" in URLs to prevent splitting Graphite namespace
	))

	r.GET("/", func(c *gin.Context) {
		c.JSON(200, "Hello world!")
	})

	r.Run(":8000")
}

standalone metrics sending

package main

import (
	"fmt"
	"os"
	"time"

	metrics "github.com/bmc-toolbox/gin-go-metrics"
)

func main() {
	err := metrics.Setup(
		"graphite",  // clientType
		"localhost", // graphite host
		2003,        // graphite port
		"server",    // metrics prefix
		time.Minute, // graphite flushInterval
	)
	if err != nil {
		fmt.Printf("Failed to set up monitoring: %s\n", err)
		os.Exit(1)
	}
	// collect data using provided functions with provided arguments once a minute
	go metrics.Scheduler(time.Minute, metrics.GoRuntimeStats, []string{})
	go metrics.Scheduler(time.Minute, metrics.MeasureRuntime, []string{"uptime"}, time.Now())

	//<...>
	metrics.IncrCounter([]string{"happy_routine", "happy_runs_counter"}, 1)
	metrics.UpdateGauge([]string{"happy_routine", "happiness_level"}, 9000)
	metrics.UpdateHistogram([]string{"happy_routine", "happiness_hit"}, 35)
	metrics.UpdateTimer([]string{"happy_time"}, time.Minute)
}

Provided metrics

Request processing time and count of requests stored in go-metrics.Timer

Request and response size stored in go-metrics.Histogram

Data storage

Currently only helper function for sending data to Graphite with cyberdelia/go-metrics-graphite is present, however, you can send data using go-metrics.DefaultRegistry anywhere you want.

Acknowledgment

This library was originally developed for Booking.com. With approval from Booking.com, the code and specification was generalized and published as Open Source on GitHub, for which the authors would like to express their gratitude.