pkg/cincinnati: Set User-Agent for Cincinnati requests

pkg/cincinnati/cincinnati.go

@@ -32,11 +32,20 @@ const (
 type Client struct {
 	id        uuid.UUID
 	transport *http.Transport
+
+	// userAgent configures the User-Agent header for upstream
+	// requests.  If empty, the User-Agent header will not be
+	// populated.
+	userAgent string
 }
 
 // NewClient creates a new Cincinnati client with the given client identifier.
-func NewClient(id uuid.UUID, transport *http.Transport) Client {
-	return Client{id: id, transport: transport}
+func NewClient(id uuid.UUID, transport *http.Transport, userAgent string) Client {
+	return Client{
+		id:        id,
+		transport: transport,
+		userAgent: userAgent,
+	}
 }
 
 // Error is returned when are unable to get updates.
@@ -92,7 +101,11 @@ func (c Client) GetUpdates(ctx context.Context, uri *url.URL, desiredArch, curre
 	if err != nil {
 		return current, nil, nil, &Error{Reason: "InvalidRequest", Message: err.Error(), cause: err}
 	}
-	req.Header.Add("Accept", GraphMediaType)
+
+	if c.userAgent != "" {
+		req.Header.Set("User-Agent", c.userAgent)
+	}
+	req.Header.Set("Accept", GraphMediaType)
 	if c.transport != nil && c.transport.TLSClientConfig != nil {
 		if c.transport.TLSClientConfig.ClientCAs == nil {
 			klog.V(2).Infof("Using a root CA pool with 0 root CA subjects to request updates from %s", uri)

pkg/cincinnati/cincinnati_test.go

@@ -745,7 +745,7 @@ func TestGetUpdates(t *testing.T) {
 			ts := httptest.NewServer(http.HandlerFunc(handler))
 			defer ts.Close()
 
-			c := NewClient(clientID, nil)
+			c := NewClient(clientID, nil, "")
 
 			uri, err := url.Parse(ts.URL)
 			if err != nil {

pkg/cvo/availableupdates.go

@@ -67,8 +67,10 @@ func (optr *Operator) syncAvailableUpdates(ctx context.Context, config *configv1
 		return err
 	}
 
+	userAgent := optr.getUserAgent()
+
 	current, updates, conditionalUpdates, condition := calculateAvailableUpdatesStatus(ctx, string(config.Spec.ClusterID),
-		transport, upstream, desiredArch, currentArch, channel, optr.release.Version)
+		transport, userAgent, upstream, desiredArch, currentArch, channel, optr.release.Version)
 
 	if usedDefaultUpstream {
 		upstream = ""
@@ -211,7 +213,7 @@ func (optr *Operator) getDesiredArchitecture(update *configv1.Update) string {
 	return ""
 }
 
-func calculateAvailableUpdatesStatus(ctx context.Context, clusterID string, transport *http.Transport, upstream, desiredArch,
+func calculateAvailableUpdatesStatus(ctx context.Context, clusterID string, transport *http.Transport, userAgent, upstream, desiredArch,
 	currentArch, channel, version string) (configv1.Release, []configv1.Release, []configv1.ConditionalUpdate,
 	configv1.ClusterOperatorStatusCondition) {
 
@@ -269,7 +271,7 @@ func calculateAvailableUpdatesStatus(ctx context.Context, clusterID string, tran
 		}
 	}
 
-	current, updates, conditionalUpdates, err := cincinnati.NewClient(uuid, transport).GetUpdates(ctx, upstreamURI, desiredArch,
+	current, updates, conditionalUpdates, err := cincinnati.NewClient(uuid, transport, userAgent).GetUpdates(ctx, upstreamURI, desiredArch,
 		currentArch, channel, currentVersion)
 
 	if err != nil {

pkg/cvo/egress.go

@@ -10,8 +10,19 @@ import (
 
 	"golang.org/x/net/http/httpproxy"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
+
+	"github.com/openshift/cluster-version-operator/pkg/version"
 )
 
+// Returns a User-Agent to be used for outgoing HTTP requests.
+//
+// https://www.rfc-editor.org/rfc/rfc7231#section-5.5.3
+func (optr *Operator) getUserAgent() string {
+	token := "ClusterVersionOperator"
+	productVersion := version.Version
+	return fmt.Sprintf("%s/%s", token, productVersion)
+}
+
 // getTransport constructs an HTTP transport configuration, including
 // any custom proxy configuration.
 func (optr *Operator) getTransport() (*http.Transport, error) {