Add User-Agent to request made by the registry

updater/fetch.go

@@ -27,16 +27,9 @@ func (reg *ResourceRegistry) fetchFile(ctx context.Context, client *http.Client,
 		}
 	}
 
-	// create URL
-	downloadURL, err := joinURLandPath(reg.UpdateURLs[tries%len(reg.UpdateURLs)], rv.versionedPath())
-	if err != nil {
-		return fmt.Errorf("error build url (%s + %s): %w", reg.UpdateURLs[tries%len(reg.UpdateURLs)], rv.versionedPath(), err)
-	}
-
 	// check destination dir
 	dirPath := filepath.Dir(rv.storagePath())
-
+	err := reg.storageDir.EnsureAbsPath(dirPath)
-	err = reg.storageDir.EnsureAbsPath(dirPath)
 	if err != nil {
 		return fmt.Errorf("could not create updates folder: %s", dirPath)
 	}
@@ -49,27 +42,19 @@ func (reg *ResourceRegistry) fetchFile(ctx context.Context, client *http.Client,
 	defer atomicFile.Cleanup() //nolint:errcheck // ignore error for now, tmp dir will be cleaned later again anyway
 
 	// start file download
-	req, err := http.NewRequestWithContext(ctx, "GET", downloadURL, http.NoBody) //nolint:gosec
+	resp, downloadURL, err := reg.makeRequest(ctx, client, rv.versionedPath(), tries)
 	if err != nil {
-		return fmt.Errorf("error creating request (%s): %w", downloadURL, err)
+		return err
-	}
-	resp, err := client.Do(req)
-	if err != nil {
-		return fmt.Errorf("error fetching url (%s): %w", downloadURL, err)
 	}
 	defer resp.Body.Close()
 
-	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("error fetching url (%s): %s", downloadURL, resp.Status)
-	}
-
 	// download and write file
 	n, err := io.Copy(atomicFile, resp.Body)
 	if err != nil {
-		return fmt.Errorf("failed downloading %s: %w", downloadURL, err)
+		return fmt.Errorf("failed to download %q: %w", downloadURL, err)
 	}
 	if resp.ContentLength != n {
-		return fmt.Errorf("download unfinished, written %d out of %d bytes", n, resp.ContentLength)
+		return fmt.Errorf("failed to finish download of %q: written %d out of %d bytes", downloadURL, n, resp.ContentLength)
 	}
 
 	// finalize file
@@ -100,46 +85,60 @@ func (reg *ResourceRegistry) fetchData(ctx context.Context, client *http.Client,
 		}
 	}
 
-	// create URL
-	downloadURL, err := joinURLandPath(reg.UpdateURLs[tries%len(reg.UpdateURLs)], downloadPath)
-	if err != nil {
-		return nil, fmt.Errorf("error build url (%s + %s): %w", reg.UpdateURLs[tries%len(reg.UpdateURLs)], downloadPath, err)
-	}
-
 	// start file download
-	req, err := http.NewRequestWithContext(ctx, "GET", downloadURL, http.NoBody) //nolint:gosec
+	resp, downloadURL, err := reg.makeRequest(ctx, client, downloadPath, tries)
 	if err != nil {
-		return nil, fmt.Errorf("error creating request (%s): %w", downloadURL, err)
+		return nil, err
-	}
-	resp, err := client.Do(req)
-	if err != nil {
-		return nil, fmt.Errorf("error fetching url (%s): %w", downloadURL, err)
 	}
 	defer resp.Body.Close()
 
-	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("error fetching url (%s): %s", downloadURL, resp.Status)
-	}
-
 	// download and write file
 	buf := bytes.NewBuffer(make([]byte, 0, resp.ContentLength))
 	n, err := io.Copy(buf, resp.Body)
 	if err != nil {
-		return nil, fmt.Errorf("failed downloading %s: %w", downloadURL, err)
+		return nil, fmt.Errorf("failed to download %q: %w", downloadURL, err)
 	}
 	if resp.ContentLength != n {
-		return nil, fmt.Errorf("download unfinished, written %d out of %d bytes", n, resp.ContentLength)
+		return nil, fmt.Errorf("failed to finish download of %q: written %d out of %d bytes", downloadURL, n, resp.ContentLength)
 	}
 
 	return buf.Bytes(), nil
 }
 
-func joinURLandPath(baseURL, urlPath string) (string, error) {
+func (reg *ResourceRegistry) makeRequest(ctx context.Context, client *http.Client, downloadPath string, tries int) (resp *http.Response, downloadURL string, err error) {
-	u, err := url.Parse(baseURL)
+	// parse update URL
+	updateBaseURL := reg.UpdateURLs[tries%len(reg.UpdateURLs)]
+	u, err := url.Parse(updateBaseURL)
 	if err != nil {
-		return "", err
+		return nil, "", fmt.Errorf("failed to parse update URL %q: %w", updateBaseURL, err)
+	}
+	// add download path
+	u.Path = path.Join(u.Path, downloadPath)
+	// compile URL
+	downloadURL = u.String()
+
+	// create request
+	req, err := http.NewRequestWithContext(ctx, "GET", downloadURL, http.NoBody) //nolint:gosec
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to create request for %q: %w", downloadURL, err)
 	}
 
-	u.Path = path.Join(u.Path, urlPath)
+	// set user agent
-	return u.String(), nil
+	if reg.UserAgent != "" {
+		req.Header.Set("User-Agent", reg.UserAgent)
+	}
+
+	// start request
+	resp, err = client.Do(req)
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to make request to %q: %w", downloadURL, err)
+	}
+
+	// check return code
+	if resp.StatusCode != http.StatusOK {
+		resp.Body.Close()
+		return nil, "", fmt.Errorf("failed to fetch %q: %d %s", downloadURL, resp.StatusCode, resp.Status)
+	}
+
+	return resp, downloadURL, err
 }

updater/registry.go

@@ -24,6 +24,7 @@ type ResourceRegistry struct {
 
 	resources        map[string]*Resource
 	UpdateURLs       []string
+	UserAgent        string
 	MandatoryUpdates []string
 
 	Beta    bool