Mentor Review | Output and Error Handling | Mohammed Suara

projects/output-and-error-handling/go.mod

@@ -0,0 +1,3 @@
+module github.com/CodeYourFuture/immersive-go-course/projects/output-and-error-handling
+
+go 1.21.5

projects/output-and-error-handling/main.go

@@ -0,0 +1,61 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"strconv"
+	"time"
+)
+
+func main() {
+
+	client := &http.Client{Timeout: time.Duration(1) * time.Second}
+
+	response, err := client.Get("http://localhost:8080")
+	if err != nil {
+		fmt.Fprint(os.Stderr, "Server is down. Please try again later\t")
+		os.Exit(1)
+	}
+
+	defer response.Body.Close()
+
+	if response.StatusCode == http.StatusOK {
+		body, err := io.ReadAll(response.Body)
+		if err != nil {
+			fmt.Fprint(os.Stderr, "Response body could not be read: ", err)
+			os.Exit(2)
+		}
+		fmt.Fprintln(os.Stdout, string(body))
+	} else if response.StatusCode == http.StatusTooManyRequests {
+		handleRetry(response)
+	} else {
+		fmt.Fprintf(os.Stderr, "Unexpected response: %d\n", response.StatusCode)
+		os.Exit(4)
+	}
+
+
+}
+
+func handleRetry(res *http.Response) {
+
+	retryHeader := res.Header.Get("Retry-After")
+	parsedTime, err := http.ParseTime(retryHeader)
+	if err == nil {
+		waitTime := time.Until(parsedTime)
+		fmt.Printf("You have to wait for %vsecs to restart the application", int64(waitTime/time.Second))
+		time.Sleep(waitTime)
+	} else {
+		waitSecs, err := strconv.Atoi(retryHeader)
+		if err == nil {
+			fmt.Printf("You have to wait for %dsecs to start the application again", waitSecs)
+			time.Sleep(time.Duration(waitSecs) * time.Second)
+		} else {
+			fmt.Fprint(os.Stderr, "Invalid Retry Header!!!\t")
+			os.Exit(3)
+		}
+	}
+
+	defer res.Body.Close()
+}