Fix issue with stale device lists (#2702)

We were only sending the last entry to the worker, so most likely missed
updates.

federationapi/inthttp/server.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"net/http"
+	"net/url"
 
 	"github.com/gorilla/mux"
 	"github.com/matrix-org/gomatrix"
@@ -235,9 +236,17 @@ func federationClientError(err error) error {
 		return &api.FederationClientError{
 			Code: ferr.Code,
 		}
-	default:
+	case *url.Error: // e.g. certificate error, unable to connect
 		return &api.FederationClientError{
-			Err: err.Error(),
+			Err:  ferr.Error(),
+			Code: 400,
+		}
+	default:
+		// We don't know what exactly failed, but we probably don't
+		// want to retry the request immediately in the device list updater
+		return &api.FederationClientError{
+			Err:  err.Error(),
+			Code: 400,
 		}
 	}
 }

keyserver/internal/device_list_update.go

@@ -167,6 +167,7 @@ func (u *DeviceListUpdater) Start() error {
 		step = (time.Second * 120) / time.Duration(max)
 	}
 	for _, userID := range staleLists {
+		userID := userID // otherwise we are only sending the last entry
 		time.AfterFunc(offset, func() {
 			u.notifyWorkers(userID)
 		})
@@ -396,11 +397,19 @@ userLoop:
 		if ctx.Err() != nil {
 			// we've timed out, give up and go to the back of the queue to let another server be processed.
 			failCount += 1
+			waitTime = time.Minute * 10
 			break
 		}
 		res, err := u.fedClient.GetUserDevices(ctx, serverName, userID)
 		if err != nil {
 			failCount += 1
+			select {
+			case <-ctx.Done():
+				// we've timed out, give up and go to the back of the queue to let another server be processed.
+				waitTime = time.Minute * 10
+				break userLoop
+			default:
+			}
 			switch e := err.(type) {
 			case *fedsenderapi.FederationClientError:
 				if e.RetryAfter > 0 {
@@ -419,7 +428,7 @@ userLoop:
 				// It probably doesn't make sense to try further users.
 				if !e.Timeout() {
 					waitTime = time.Minute * 10
-					logrus.WithError(e).Error("GetUserDevices returned net.Error")
+					logger.WithError(e).Error("GetUserDevices returned net.Error")
 					break userLoop
 				}
 			case gomatrix.HTTPError:
@@ -427,7 +436,7 @@ userLoop:
 				// This is to avoid spamming remote servers, which may not be Matrix servers anymore.
 				if e.Code >= 300 {
 					waitTime = time.Hour
-					logrus.WithError(e).Error("GetUserDevices returned gomatrix.HTTPError")
+					logger.WithError(e).Error("GetUserDevices returned gomatrix.HTTPError")
 					break userLoop
 				}
 			default: