namespace: Don't return errors for Mount/Unmount if all routing ids have
successful returns.
A mount table may be mounted many times in one place if it has endpoints
on multiple networks. Before this change Mount would return an error if
a Mount attempt on any of these networks failed. Now it only returns an
error if all mounts to the same routing id fail.
Change-Id: I3ebfa06395768701367221e0e355303841611688
diff --git a/runtimes/google/naming/namespace/mount.go b/runtimes/google/naming/namespace/mount.go
index f82d5b3..ac2e875 100644
--- a/runtimes/google/naming/namespace/mount.go
+++ b/runtimes/google/naming/namespace/mount.go
@@ -3,6 +3,8 @@
import (
"time"
+ inaming "veyron.io/veyron/veyron/runtimes/google/naming"
+
"veyron.io/veyron/veyron2/context"
"veyron.io/veyron/veyron2/ipc"
"veyron.io/veyron/veyron2/naming"
@@ -10,30 +12,93 @@
"veyron.io/veyron/veyron2/vlog"
)
+type status struct {
+ id string
+ err error
+}
+
// mountIntoMountTable mounts a single server into a single mount table.
-func mountIntoMountTable(ctx context.T, client ipc.Client, name, server string, ttl time.Duration, flags naming.MountFlag) error {
+func mountIntoMountTable(ctx context.T, client ipc.Client, name, server string, ttl time.Duration, flags naming.MountFlag, id string) (s status) {
+ s.id = id
ctx, _ = ctx.WithTimeout(callTimeout)
call, err := client.StartCall(ctx, name, "Mount", []interface{}{server, uint32(ttl.Seconds()), flags}, options.NoResolve(true))
+ s.err = err
if err != nil {
- return err
+ return
}
if ierr := call.Finish(&err); ierr != nil {
- return ierr
+ s.err = ierr
}
- return err
+ return
}
// unmountFromMountTable removes a single mounted server from a single mount table.
-func unmountFromMountTable(ctx context.T, client ipc.Client, name, server string) error {
+func unmountFromMountTable(ctx context.T, client ipc.Client, name, server string, id string) (s status) {
+ s.id = id
ctx, _ = ctx.WithTimeout(callTimeout)
call, err := client.StartCall(ctx, name, "Unmount", []interface{}{server}, options.NoResolve(true))
+ s.err = err
+ if err != nil {
+ return
+ }
+ if ierr := call.Finish(&err); ierr != nil {
+ s.err = ierr
+ }
+ return
+}
+
+// nameToRID converts a name to a routing ID string. If a routing ID can't be obtained,
+// it just returns the name.
+func nameToRID(name string) string {
+ address, _ := naming.SplitAddressName(name)
+ if ep, err := inaming.NewEndpoint(address); err == nil {
+ return ep.RID.String()
+ }
+ return name
+}
+
+// collectStati collects n status messages from channel c and returns an error if, for
+// any id, there is no successful reply.
+func collectStati(c chan status, n int) error {
+ // Make a map indexed by the routing id (or address if routing id not found) of
+ // each mount table. A mount table may be reachable via multiple addresses but
+ // each address should have the same routing id. We should only return an error
+ // if any of the ids had no successful mounts.
+ statusByID := make(map[string]error)
+ // Get the status of each request.
+ for i := 0; i < n; i++ {
+ s := <-c
+ if _, ok := statusByID[s.id]; !ok || s.err == nil {
+ statusByID[s.id] = s.err
+ }
+ }
+ // Return any error.
+ for _, s := range statusByID {
+ if s != nil {
+ return s
+ }
+ }
+ return nil
+}
+
+// dispatch executes f in parallel for each mount table implementing mTName.
+func (ns *namespace) dispatch(ctx context.T, mTName string, f func(context.T, string, string) status) error {
+ // Resolve to all the mount tables implementing name.
+ mts, err := ns.ResolveToMountTable(ctx, mTName)
if err != nil {
return err
}
- if ierr := call.Finish(&err); ierr != nil {
- return ierr
+ // Apply f to each of the returned mount tables.
+ c := make(chan status, len(mts))
+ for _, mt := range mts {
+ go func(mt string) {
+ c <- f(ctx, mt, nameToRID(mt))
+ }(mt)
}
- return err
+ finalerr := collectStati(c, len(mts))
+ // Forget any previous cached information about these names.
+ ns.resolutionCache.forget(mts)
+ return finalerr
}
func (ns *namespace) Mount(ctx context.T, name, server string, ttl time.Duration, opts ...naming.MountOpt) error {
@@ -53,55 +118,22 @@
}
}
}
-
- // Resolve to all the mount tables implementing name.
- mtServers, err := ns.ResolveToMountTable(ctx, name)
- if err != nil {
- return err
- }
// Mount the server in all the returned mount tables.
- c := make(chan error, len(mtServers))
- for _, mt := range mtServers {
- go func() {
- c <- mountIntoMountTable(ctx, ns.rt.Client(), mt, server, ttl, flags)
- }()
+ f := func(ctx context.T, mt, id string) status {
+ return mountIntoMountTable(ctx, ns.rt.Client(), mt, server, ttl, flags, id)
}
- // Return error if any mounts failed, since otherwise we'll get
- // inconsistent resolutions down the road.
- var finalerr error
- for _ = range mtServers {
- if err := <-c; err != nil {
- finalerr = err
- }
- }
- vlog.VI(1).Infof("Mount(%s, %s) -> %v", name, server, finalerr)
- // Forget any previous cached information about these names.
- ns.resolutionCache.forget(mtServers)
- return finalerr
+ err := ns.dispatch(ctx, name, f)
+ vlog.VI(1).Infof("Mount(%s, %s) -> %v", name, server, err)
+ return err
}
func (ns *namespace) Unmount(ctx context.T, name, server string) error {
defer vlog.LogCall()()
- mts, err := ns.ResolveToMountTable(ctx, name)
- if err != nil {
- return err
- }
-
// Unmount the server from all the mount tables.
- c := make(chan error, len(mts))
- for _, mt := range mts {
- go func() {
- c <- unmountFromMountTable(ctx, ns.rt.Client(), mt, server)
- }()
+ f := func(ctx context.T, mt, id string) status {
+ return unmountFromMountTable(ctx, ns.rt.Client(), mt, server, id)
}
- // Return error if any mounts failed, since otherwise we'll get
- // inconsistent resolutions down the road.
- var finalerr error
- for _ = range mts {
- if err := <-c; err != nil {
- finalerr = err
- }
- }
- ns.resolutionCache.forget(mts)
- return finalerr
+ err := ns.dispatch(ctx, name, f)
+ vlog.VI(1).Infof("Unmount(%s, %s) -> %v", name, server, err)
+ return err
}
