It's dummy server for the "peculiar crawler" problem

server.go

package main

import (
	"fmt"
	"math/rand"
	"net/http"
	"time"

	"github.com/gin-gonic/gin"
)

const (
	no_of_id = 1000000
)

type User struct {
	Name string
	Age  int
}

var userTable map[string]User

func userHandler(c *gin.Context) {
	id := c.Param("id")
	c.JSON(http.StatusOK, userTable[id])
}

func main() {
	userTable = make(map[string]User)
	rand.Seed(time.Now().UTC().UnixNano())
	for i := 1; i <= no_of_id; i++ {
		newuser := User{
			Name: fmt.Sprintf("user %d", i),
		}
		//random number between 10 to 60
		newuser.Age = rand.Intn(50) + 10
		userTable[fmt.Sprintf("%d", i)] = newuser
	}
	router := gin.Default()
	router.GET("/user/:id", userHandler)
	router.Run(":8080")
}