package main

import (
    "errors"
    "log"
    "runtime"
    "time"
)

type Something struct {
    Id   int64
    Data []byte
}

type getSomethingResult struct {
    Something *Something
    Error     error
}

func GetSomething(id int64) (*Something, error) {
    result := make(chan getSomethingResult, 1)
    go func() {
        result <- doGetSomething(id)
    }()
    select {
    case <-time.After(5 * time.Second):
        return nil, errors.New("timed out")
    case result := <-result:
        return result.Something, result.Error
    }
}

func doGetSomething(id int64) getSomethingResult {
    time.Sleep(50 * time.Second)
    return getSomethingResult{
        Something: &Something{
            Id:   0,
            Data: nil,
        },
        Error: nil,
    }
}

func main() {
    for i := 0; i < 50; i++ {
        go GetSomething(1)
    }

    for {

        select {
        case <-time.After(1 * time.Second):
            log.Println(runtime.NumGoroutine()) // 51 goroutines are running in 5 seconds which is not good
        }

    }
}