`linkerd check` sends params on version check (#1642)

The `linkerd check` parameter hits
https://versioncheck.linkerd.io/version.json to check for the latest
Linkerd version. This loses information, as that endpoint is intended to
record current version, uuid, and source.

Modify `linkerd check` to set `version`, `uuid`, and `source`
parameters when performing a version check.

Part of #1604.

Signed-off-by: Andrew Seigner <siggy@buoyant.io>

pkg/healthcheck/healthcheck.go

@@ -98,12 +98,13 @@ type HealthChecker struct {
 	*HealthCheckOptions
 
 	// these fields are set in the process of running checks
-	kubeAPI       *k8s.KubernetesAPI
-	httpClient    *http.Client
-	kubeVersion   *k8sVersion.Info
-	apiClient     pb.ApiClient
-	dataPlanePods []v1.Pod
-	latestVersion string
+	kubeAPI          *k8s.KubernetesAPI
+	httpClient       *http.Client
+	kubeVersion      *k8sVersion.Info
+	controlPlanePods []v1.Pod
+	apiClient        pb.ApiClient
+	dataPlanePods    []v1.Pod
+	latestVersion    string
 }
 
 func NewHealthChecker(checks []Checks, options *HealthCheckOptions) *HealthChecker {
@@ -201,11 +202,12 @@ func (hc *HealthChecker) addLinkerdAPIChecks() {
 		retry:       hc.ShouldRetry,
 		fatal:       true,
 		check: func() error {
-			pods, err := hc.kubeAPI.GetPodsByNamespace(hc.httpClient, hc.ControlPlaneNamespace)
+			var err error
+			hc.controlPlanePods, err = hc.kubeAPI.GetPodsByNamespace(hc.httpClient, hc.ControlPlaneNamespace)
 			if err != nil {
 				return err
 			}
-			return validateControlPlanePods(pods)
+			return validateControlPlanePods(hc.controlPlanePods)
 		},
 	})
 
@@ -298,7 +300,23 @@ func (hc *HealthChecker) addLinkerdVersionChecks() {
 			if hc.VersionOverride != "" {
 				hc.latestVersion = hc.VersionOverride
 			} else {
-				hc.latestVersion, err = version.GetLatestVersion()
+				// The UUID is only known to the web process. At some point we may want
+				// to consider providing it in the Public API.
+				uuid := "unknown"
+				for _, pod := range hc.controlPlanePods {
+					if strings.Split(pod.Name, "-")[0] == "web" {
+						for _, container := range pod.Spec.Containers {
+							if container.Name == "web" {
+								for _, arg := range container.Args {
+									if strings.HasPrefix(arg, "-uuid=") {
+										uuid = strings.TrimPrefix(arg, "-uuid=")
+									}
+								}
+							}
+						}
+					}
+				}
+				hc.latestVersion, err = version.GetLatestVersion(uuid, "cli")
 			}
 			return
 		},

pkg/version/version.go

@@ -18,7 +18,7 @@ var Version = undefinedVersion
 
 const (
 	undefinedVersion = "undefined"
-	versionCheckURL  = "https://versioncheck.linkerd.io/version.json"
+	versionCheckURL  = "https://versioncheck.linkerd.io/version.json?version=%s&uuid=%s&source=%s"
 )
 
 func init() {
@@ -61,8 +61,9 @@ func CheckServerVersion(apiClient pb.ApiClient, latestVersion string) error {
 	return nil
 }
 
-func GetLatestVersion() (string, error) {
-	req, err := http.NewRequest("GET", versionCheckURL, nil)
+func GetLatestVersion(uuid string, source string) (string, error) {
+	url := fmt.Sprintf(versionCheckURL, Version, uuid, source)
+	req, err := http.NewRequest("GET", url, nil)
 	if err != nil {
 		return "", err
 	}

web/app/js/components/Sidebar.jsx

@@ -85,7 +85,7 @@ class Sidebar extends React.Component {
   }
 
   fetchVersion() {
-    let versionUrl = `https://versioncheck.linkerd.io/version.json?version=${this.props.releaseVersion}&uuid=${this.props.uuid}`;
+    let versionUrl = `https://versioncheck.linkerd.io/version.json?version=${this.props.releaseVersion}&uuid=${this.props.uuid}&source=web`;
     fetch(versionUrl, { credentials: 'include' })
       .then(rsp => rsp.json())
       .then(versionRsp =>