package main

import (
    "context"
    "database/sql"
    "net/http"
    "time"

    "github.com/etherlabsio/healthcheck"
    "github.com/etherlabsio/healthcheck/checkers"
    _ "github.com/go-sql-driver/mysql"
    "github.com/gorilla/mux"
)

func main() {
    // For brevity, error check is being omitted here.
    db, _ := sql.Open("mysql", "user:password@/dbname")
    defer db.Close()

    r := mux.NewRouter()
    r.Handle("/healthcheck", healthcheck.Handler(

        // WithTimeout allows you to set a max overall timeout.
        healthcheck.WithTimeout(5*time.Second),

        // Checkers fail the status in case of any error.
        healthcheck.WithChecker(
            "heartbeat", checkers.Heartbeat("$PROJECT_PATH/heartbeat"),
        ),

        healthcheck.WithChecker(
            "database", healthcheck.CheckerFunc(
                func(ctx context.Context) error {
                    return db.PingContext(ctx)
                },
            ),
        ),

        // Observers do not fail the status in case of error.
        healthcheck.WithObserver(
            "diskspace", checkers.DiskSpace("/var/log", 90),
        ),
    ))

    http.ListenAndServe(":8080", r)
}