fix: adjust some code structure to satisfy linter

internal/downloader/downloader.go

@@ -40,7 +40,10 @@ func (c *Context) Download() error {
 		}
 		return err
 	}
-	defer resp.Close()
+	if err = resp.Close(); err != nil {
+		return err
+	}
+
 	if resp.StatusCode == http.StatusNotFound {
 		return ErrInvalidURL
 	}
@@ -50,19 +53,19 @@ func (c *Context) Download() error {
 	if resp.StatusCode != http.StatusOK {
 		return errors.New(resp.RawResponse.Status)
 	}
-	resp.Close()
 
 	resp, err = req.Get(c.Link, nil)
 	if err != nil {
 		return err
 	}
+	defer resp.Close()
 
 	var filesize int64
 	if resp.RawResponse.ContentLength > -1 {
 		filesize = resp.RawResponse.ContentLength
 	}
 
-	destFile, err := os.OpenFile(c.Filename, os.O_CREATE|os.O_WRONLY, 0644)
+	destFile, err := os.OpenFile(c.Filename, os.O_CREATE|os.O_WRONLY, 0600)
 	if err != nil {
 		return err
 	}

internal/downloader/downloader_test.go

@@ -58,7 +58,10 @@ func TestDownload(t *testing.T) {
 
 	t.Run("CertificateError", func(t *testing.T) {
 		// This test assumes a self-signed certificate or similar issue. This is hard to simulate in a unit test.
-		ctx := downloader.NewContext("test_cert_error.txt", "https://self-signed.badssl.com/") // Example URL that can be used
+		ctx := downloader.NewContext(
+			"test_cert_error.txt",
+			"https://self-signed.badssl.com/", // Example URL that can be used
+		)
 
 		if err := ctx.Download(); err == nil || err.Error() != "certificate from unknown authority" {
 			t.Errorf("expected certificate from unknown authority error, got %v", err)