16561: Replace ListenAddr with per-internal-url ListenURL.

[arvados.git] / lib / service / cmd.go

diff --git a/lib/service/cmd.go b/lib/service/cmd.go
index 92c554ce532386352b3ecf766b3dcd8b2b885fb8..5687ec1dadcddb3f3f6a1e3458a46eeca45dc990 100644 (file)
--- a/lib/service/cmd.go
+++ b/lib/service/cmd.go
@@ -223,6 +223,18 @@ func interceptHealthReqs(mgtToken string, checkHealth func() error, next http.Ha
        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 {
@@ -236,51 +248,34 @@ func getListenAddr(svcs arvados.Services, prog arvados.ServiceName, log logrus.F
                if url.Path == "" {
                        url.Path = "/"
                }
-               internalURL := arvados.URL(*url)
-               listenURL := arvados.URL(*url)
-               if svc.ListenAddress != "" {
-                       listenURL.Host = svc.ListenAddress
-               }
-               return listenURL, internalURL, nil
-       }
-
-       if svc.ListenAddress != "" {
-               scheme := ""
-               for internalURL := range svc.InternalURLs {
-                       if internalURL.Host == svc.ListenAddress {
-                               if len(svc.InternalURLs) > 1 {
-                                       log.Warnf("possible configuration error: multiple InternalURLs entries exist for %s but only %q will ever be used because it matches ListenAddress", prog, internalURL.String())
+               for internalURL, conf := range svc.InternalURLs {
+                       if internalURL.String() == url.String() {
+                               listenURL := conf.ListenURL
+                               if listenURL.Host == "" {
+                                       listenURL = internalURL
                                }
-                               return internalURL, internalURL, nil
+                               return listenURL, internalURL, nil
                        }
-                       switch scheme {
-                       case "":
-                               scheme = internalURL.Scheme
-                       case internalURL.Scheme:
-                       default:
-                               scheme = "-" // different InternalURLs have different schemes
-                       }
-               }
-               if scheme == "-" {
-                       return arvados.URL{}, arvados.URL{}, fmt.Errorf("cannot use ListenAddress %q: InternalURLs use multiple schemes and none have host %q", svc.ListenAddress, svc.ListenAddress)
-               }
-               if scheme == "" {
-                       // No entries at all in InternalURLs
-                       scheme = "http"
                }
-               listenURL := arvados.URL{}
-               listenURL.Host = svc.ListenAddress
-               listenURL.Scheme = scheme
-               listenURL.Path = "/"
-               return listenURL, listenURL, 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 := range svc.InternalURLs {
-               listener, err := net.Listen("tcp", internalURL.Host)
+       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
+               }
+               listener, err := net.Listen("tcp", listenURL.Host)
                if err == nil {
                        listener.Close()
-                       return internalURL, internalURL, nil
+                       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
@@ -288,7 +283,7 @@ func getListenAddr(svcs arvados.Services, prog arvados.ServiceName, log logrus.F
                        // can't bind an IP address it doesn't own.
                        continue
                } else {
-                       errors = append(errors, fmt.Sprintf("tried %v, got %v", internalURL, err))
+                       errors = append(errors, fmt.Sprintf("%s: %s", listenURL, err))
                }
        }
        if len(errors) > 0 {