checkpoint: download and read HTML

main.go

@@ -3,7 +3,11 @@ package main
 import (
 	"errors"
 	"fmt"
+	"io"
+	"net/http"
 	"os"
+	"strings"
+	"time"
 )
 
 var (
@@ -33,7 +37,51 @@ func run() error {
 
 	baseURL := args[0]
 
-	fmt.Printf("starting crawl of: %s\n", baseURL)
+	htmlBody, err := getHTML(baseURL)
+	if err != nil {
+		return err
+	}
+
+	fmt.Println(htmlBody)
 
 	return nil
 }
+
+func getHTML(rawURL string) (string, error) {
+	req, err := http.NewRequest(http.MethodGet, rawURL, nil)
+	if err != nil {
+		return "", fmt.Errorf("error creating the request: %w", err)
+	}
+
+	client := http.Client{
+		Timeout: time.Duration(10 * time.Second),
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return "", fmt.Errorf("error getting the response: %w", err)
+	}
+
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		return "", fmt.Errorf(
+			"received a bad status from %s: (%d) %s",
+			rawURL,
+			resp.StatusCode,
+			resp.Status,
+		)
+	}
+
+	contentType := resp.Header.Get("content-type")
+	if !strings.Contains(contentType, "text/html") {
+		return "", fmt.Errorf("unexpected content type received: want text/html, got %s", contentType)
+	}
+
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", fmt.Errorf("error reading the data from the response: %w", err)
+	}
+
+	return string(data), nil
+}