Golang run and wait for many go routines using channels and returning a struct of result data for each process

main.go

package main

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

type SystemCommandResult struct {
	ExitCode     int
	OutputString string
	RunTime      string
}

const numberOfJobs = 50

func longTimeRequest() <-chan SystemCommandResult {
	r := make(chan SystemCommandResult)
	go func() {
		// Simulate a workload with random duration
		waitTime := rand.Int31n(5)
		time.Sleep(time.Second * time.Duration(waitTime))
		randomNumber := rand.Int31n(100)
		result := SystemCommandResult{
			ExitCode:     0,
			OutputString: fmt.Sprintf("workload completed [%d]", randomNumber),
			RunTime:      fmt.Sprintf("%d seconds", waitTime),
		}
		r <- result
	}()
	return r
}

func waitForChannel(r SystemCommandResult) SystemCommandResult {
	return SystemCommandResult{
		ExitCode:     r.ExitCode,
		OutputString: r.OutputString,
		RunTime:      r.RunTime,
	}
}

func main() {
	rand.Seed(time.Now().UnixNano()) // before Go 1.20

	// list of channels
	var resultChannels []<-chan SystemCommandResult

	// create channels
	for i := 0; i < numberOfJobs; i++ {
		resultChannels = append(resultChannels, longTimeRequest())
	}

	// iterate over channels
	for id, resultChannel := range resultChannels {
		currentResult := waitForChannel(<-resultChannel)
		log.Printf("[%d] exit : %d, output : %s, time : %s\n", id, currentResult.ExitCode, currentResult.OutputString, currentResult.RunTime)
	}
}