+// If an incoming request's target vhost has an embedded collection
+// UUID or PDH, handle it with hTrue, otherwise handle it with
+// hFalse.
+//
+// Facilitates routing "http://collections.example/metrics" to metrics
+// and "http://{uuid}.collections.example/metrics" to a file in a
+// collection.
+func ifCollectionInHost(hTrue, hFalse http.Handler) http.Handler {
+ return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ if arvados.CollectionIDFromDNSName(r.Host) != "" {
+ hTrue.ServeHTTP(w, r)
+ } else {
+ hFalse.ServeHTTP(w, r)
+ }
+ })
+}
+
+func interceptHealthReqs(mgtToken string, checkHealth func() error, next http.Handler) http.Handler {
+ mux := httprouter.New()
+ mux.Handler("GET", "/_health/ping", &health.Handler{
+ Token: mgtToken,
+ Prefix: "/_health/",
+ Routes: health.Routes{"ping": checkHealth},
+ })
+ mux.NotFound = next
+ return ifCollectionInHost(next, mux)
+}
+
+// Determine listenURL (addr:port where server should bind) and
+// internalURL (target url that client should connect to) for a
+// service.
+//
+// If the config does not specify ListenURL, we check all of the
+// configured InternalURLs. If there is exactly one that matches our
+// hostname, or exactly one that matches a local interface address,
+// then we use that as listenURL.
+//
+// Note that listenURL and internalURL may use different protocols
+// (e.g., listenURL is http, but the service sits behind a proxy, so
+// clients connect using https).
+func getListenAddr(svcs arvados.Services, prog arvados.ServiceName, log logrus.FieldLogger) (arvados.URL, arvados.URL, error) {
+ svc, ok := svcs.Map()[prog]
+ if !ok {
+ return arvados.URL{}, arvados.URL{}, fmt.Errorf("unknown service name %q", prog)
+ }
+
+ if want := os.Getenv("ARVADOS_SERVICE_INTERNAL_URL"); want != "" {
+ url, err := url.Parse(want)
+ if err != nil {
+ return arvados.URL{}, arvados.URL{}, fmt.Errorf("$ARVADOS_SERVICE_INTERNAL_URL (%q): %s", want, err)
+ }
+ if url.Path == "" {
+ url.Path = "/"
+ }
+ for internalURL, conf := range svc.InternalURLs {
+ if internalURL.String() == url.String() {
+ listenURL := conf.ListenURL
+ if listenURL.Host == "" {
+ listenURL = internalURL
+ }
+ return listenURL, internalURL, nil
+ }
+ }
+ log.Warnf("possible configuration error: listening on %s (from $ARVADOS_SERVICE_INTERNAL_URL) even though configuration does not have a matching InternalURLs entry", url)
+ internalURL := arvados.URL(*url)
+ return internalURL, internalURL, nil
+ }
+
+ errors := []string{}
+ for internalURL, conf := range svc.InternalURLs {
+ listenURL := conf.ListenURL
+ if listenURL.Host == "" {
+ // If ListenURL is not specified, assume
+ // InternalURL is also usable as the listening
+ // proto/addr/port (i.e., simple case with no
+ // intermediate proxy/routing)
+ listenURL = internalURL
+ }
+ listenAddr := listenURL.Host
+ if _, _, err := net.SplitHostPort(listenAddr); err != nil {
+ // url "https://foo.example/" (with no
+ // explicit port name/number) means listen on
+ // the well-known port for the specified
+ // protocol, "foo.example:https".
+ port := listenURL.Scheme
+ if port == "ws" || port == "wss" {
+ port = "http" + port[2:]
+ }
+ listenAddr = net.JoinHostPort(listenAddr, port)
+ }
+ listener, err := net.Listen("tcp", listenAddr)
+ if err == nil {
+ listener.Close()
+ return listenURL, internalURL, nil
+ } else if strings.Contains(err.Error(), "cannot assign requested address") {
+ // If 'Host' specifies a different server than
+ // the current one, it'll resolve the hostname
+ // to IP address, and then fail because it
+ // can't bind an IP address it doesn't own.
+ continue
+ } else {
+ errors = append(errors, fmt.Sprintf("%s: %s", listenURL, err))
+ }
+ }
+ if len(errors) > 0 {
+ return arvados.URL{}, arvados.URL{}, fmt.Errorf("could not enable the %q service on this host: %s", prog, strings.Join(errors, "; "))
+ }
+ return arvados.URL{}, arvados.URL{}, fmt.Errorf("configuration does not enable the %q service on this host", prog)
+}
+
+type contextKeyURL struct{}
+
+func URLFromContext(ctx context.Context) (arvados.URL, bool) {
+ u, ok := ctx.Value(contextKeyURL{}).(arvados.URL)
+ return u, ok
+}