Go Async

p1.go

package main

import (
	"fmt"
	"net/http"
)

func main() {
	// A slice of sample websites
	urls := []string{
		"https://www.easyjet.com/",
		"https://www.skyscanner.de/",
		"https://www.ryanair.com",
		"https://wizzair.com/",
		"https://www.swiss.com/",
	}
	for _, url := range urls {
		checkUrl(url)
	}
}

//checks and prints a message if a website is up or down
func checkUrl(url string) {
	_, err := http.Get(url)
	if err != nil {
		fmt.Println(url, "is down !!!")
		return
	}
	fmt.Println(url, "is up and running.")
}

p2.go

package main

import (
	"fmt"
	"net/http"
)

func main() {
	// A slice of sample websites
	urls := []string{
		"https://www.easyjet.com/",
		"https://www.skyscanner.de/",
		"https://www.ryanair.com",
		"https://wizzair.com/",
		"https://www.swiss.com/",
	}
	for _, url := range urls {
		go checkUrl(url)
	}
}

//checks and prints a message if a website is up or down
func checkUrl(url string) {
	_, err := http.Get(url)
	if err != nil {
		fmt.Println(url, "is down !!!")
		return
	}
	fmt.Println(url, "is up and running.")
}

p3.go

package main

import (
	"fmt"
	"net/http"
	"time"
)

func main() {
	// A slice of sample websites
	urls := []string{
		"https://www.easyjet.com/",
		"https://www.skyscanner.de/",
		"https://www.ryanair.com",
		"https://wizzair.com/",
		"https://www.swiss.com/",
	}
	for _, url := range urls {
		// Call the function check
		go checkUrl(url)
	}
	time.Sleep(5 * time.Second)
}

//checks and prints a message if a website is up or down
func checkUrl(url string) {
	_, err := http.Get(url)
	if err != nil {
		fmt.Println(url, "is down !!!")
		return
	}
	fmt.Println(url, "is up and running.")
}

p4.go

package main

import (
	"fmt"
	"net/http"
	"sync"
)

func main() {
	// A slice of sample websites
	urls := []string{
		"https://www.easyjet.com/",
		"https://www.skyscanner.de/",
		"https://www.ryanair.com",
		"https://wizzair.com/",
		"https://www.swiss.com/",
	}
	var wg sync.WaitGroup

	for _, u := range urls {
		// Increment the wait group counter
		wg.Add(1)
		go func(url string) {
			// Decrement the counter when the go routine completes
			defer wg.Done()
			// Call the function check
			checkUrl(url)
		}(u)
	}
	// Wait for all the checkWebsite calls to finish
	wg.Wait()
}

//checks and prints a message if a website is up or down
func checkUrl(url string) {
	_, err := http.Get(url)
	if err != nil {
		fmt.Println(url, "is down !!!")
		return
	}
	fmt.Println(url, "is up and running.")
}

p5.go

package main

import (
	"fmt"
	"net/http"
)

func main() {
	// A slice of sample websites
	urls := []string{
		"https://www.easyjet.com/",
		"https://www.skyscanner.de/",
		"https://www.ryanair.com",
		"https://wizzair.com/",
		"https://www.swiss.com/",
	}

	c := make(chan urlStatus)
	for _, url := range urls {
		go checkUrl(url, c)

	}
	result := make([]urlStatus, len(urls))
	for i, _ := range result {
		result[i] = <-c
		if result[i].status {
			fmt.Println(result[i].url, "is up.")
		} else {
			fmt.Println(result[i].url, "is down !!")
		}
	}

}

//checks and prints a message if a website is up or down
func checkUrl(url string, c chan urlStatus) {
	_, err := http.Get(url)
	if err != nil {
		// The website is down
		c <- urlStatus{url, false}
	} else {
		// The website is up
		c <- urlStatus{url, true}
	}
}

type urlStatus struct {
	url    string
	status bool
}