InVisionApp/go-health

package main

import (
    "fmt"
    "log"
    "net/http"
    "time"

    "github.com/InVisionApp/go-health/v2"
    "github.com/InVisionApp/go-health/v2/handlers"
)

type customCheck struct{}

func main() {
    // Create a new health instance
    h := health.New()

    // Instantiate your custom check
    cc := &customCheck{}

    // Add the checks to the health instance
    h.AddChecks([]*health.Config{
        {
            Name:     "good-check",
            Checker:  cc,
            Interval: time.Duration(2) * time.Second,
            Fatal:    true,
        },
    })

    //  Start the healthcheck process
    if err := h.Start(); err != nil {
        log.Fatalf("Unable to start healthcheck: %v", err)
    }

    log.Println("Server listening on :8080")

    // Define a healthcheck endpoint and use the built-in JSON handler
    http.HandleFunc("/healthcheck", handlers.NewJSONHandlerFunc(h, nil))
    http.ListenAndServe(":8080", nil)
}

// Satisfy the go-health.ICheckable interface
func (c *customCheck) Status() (interface{}, error) {
    // perform some sort of check
    if false {
        return nil, fmt.Errorf("Something major just broke")
    }

    // You can return additional information pertaining to the check as long
    // as it can be JSON marshalled
    return map[string]int{"foo": 123, "bar": 456}, nil
}