Select

Author: naeemaei

15-Concurrency/12-Select/examples/livescore.go

@@ -0,0 +1,114 @@
+package examples
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"time"
+)
+
+// https://footba11.co/json/liveFeed
+// https://livescore-api.varzesh3.com/v1.0/livescore/today
+
+// referer: https://www.varzesh3.com/
+
+func SelectExample1() {
+	resource1 := make(chan string)
+	resource2 := make(chan string)
+	var result = ""
+
+	go GetResponse(resource1, "https://footba11.co/json/liveFeed")
+	go GetResponse(resource2, "https://livescore-api.varzesh3.com/v1.0/livescore/today")
+
+	select {
+	case result = <-resource1:
+		println("footba11 returned")
+	case result = <-resource2:
+		println("varzesh3 returned")
+	case <-time.After(time.Second * 3):
+		println("Timeout")
+	default:
+		println("Default")
+	}
+	println(result)
+	PrintlnWithTime("End")
+}
+
+func SelectExample2() {
+	resource1 := make(chan string)
+	resource2 := make(chan string)
+	var result string
+
+	go GetResponse(resource1, "https://footba11.co/json/liveFeed")
+	go GetResponse(resource2, "https://livescore-api.varzesh3.com/v1.0/livescore/today")
+
+	for {
+		select {
+		case result = <-resource1:
+			println("footba11 returned")
+			println(result)
+			return
+		case result = <-resource2:
+			println("varzesh3 returned")
+			println(result)
+			return
+		default:
+			println("Default")
+		}
+	}
+
+}
+
+func GetResponse(content chan<- string, url string) {
+	// if url == "https://livescore-api.varzesh3.com/v1.0/livescore/today" {
+	// 	time.Sleep(time.Millisecond * 50)
+	// }
+	// time.Sleep(time.Second * 3)
+	client := http.Client{}
+
+	request, err := http.NewRequest("GET", url, nil)
+
+	ctx := context.Background()
+
+	ctx, cancel := context.WithTimeout(ctx, time.Millisecond*10000)
+	defer cancel()
+	request = request.WithContext(ctx)
+
+	if err != nil {
+		panic(err)
+	}
+
+	request.Header = http.Header{}
+	request.Header.Add("referer", "https://www.varzesh3.com/")
+
+	response, err := client.Do(request)
+
+	if err != nil {
+		panic(err)
+	}
+
+	defer response.Body.Close()
+
+	responseBody, err := ioutil.ReadAll(response.Body)
+
+	if err != nil {
+		panic(err)
+	}
+
+	destination := &bytes.Buffer{}
+
+	if err = json.Indent(destination, responseBody, "", "  "); err != nil {
+		panic(err)
+	}
+	PrintlnWithTime("Before set content")
+	content <- destination.String()
+	PrintlnWithTime("After set content")
+
+}
+
+func PrintlnWithTime(args ...any) {
+	fmt.Printf("Time: %s, %v\n", time.Now().Format(time.RFC3339Nano), args)
+}

15-Concurrency/12-Select/go.mod

@@ -0,0 +1,3 @@
+module select
+
+go 1.18

15-Concurrency/12-Select/main.go

@@ -0,0 +1,7 @@
+package main
+
+import "select/examples"
+
+func main() {
+	examples.SelectExample2()
+}