package main

import (
    "fmt"
    "math/rand"
    "strconv"
    "time"
)

type Client struct {
    id string
}

type Params struct {
    client *Client
}

var globalClient *Client

func main() {
    params := Params{client: globalClient}
    globalClient = get(params)
    fmt.Println(globalClient)

    params = Params{client: globalClient}
    globalClient = get(params)
    fmt.Println(globalClient)

    params = Params{client: globalClient}
    globalClient = get(params)
    fmt.Println(globalClient)
}

func get(params Params) *Client {
    if params.client == nil {
        return &Client{id: getRandomStrId()}
    }

    return params.client
}

func getRandomStrId() string {
    rand.Seed(time.Now().UnixNano())
    return strconv.FormatInt(int64(rand.Intn(100)), 10)
}