Federation sender API remodel (#988)

* Define an input API for the federationsender

* Wiring for rooomserver input API and federation sender input API

* Whoops, commit common too

* Merge input API into query API

* Rename FederationSenderQueryAPI to FederationSenderInternalAPI

* Fix dendritejs

* Rename Input to Perform

* Fix a couple of inputs -> performs

* Remove needless storage interface, add comments

23 files changed, 292 insertions, 135 deletions

diff --git a/clientapi/clientapi.go b/clientapi/clientapi.go
index 1339f7c8..6a857e52 100644
--- a/clientapi/clientapi.go
+++ b/clientapi/clientapi.go
@@ -44,7 +44,7 @@ func SetupClientAPIComponent(
 	eduInputAPI eduServerAPI.EDUServerInputAPI,
 	asAPI appserviceAPI.AppServiceQueryAPI,
 	transactionsCache *transactions.Cache,
-	fedSenderAPI federationSenderAPI.FederationSenderQueryAPI,
+	fsAPI federationSenderAPI.FederationSenderInternalAPI,
 ) {
 	roomserverProducer := producers.NewRoomserverProducer(inputAPI, queryAPI)
 	eduProducer := producers.NewEDUServerProducer(eduInputAPI)
@@ -69,6 +69,6 @@ func SetupClientAPIComponent(
 	routing.Setup(
 		base.APIMux, base.Cfg, roomserverProducer, queryAPI, aliasAPI, asAPI,
 		accountsDB, deviceDB, federation, *keyRing, userUpdateProducer,
-		syncProducer, eduProducer, transactionsCache, fedSenderAPI,
+		syncProducer, eduProducer, transactionsCache, fsAPI,
 	)
 }
diff --git a/clientapi/routing/directory.go b/clientapi/routing/directory.go
index 248696ab..101ba11f 100644
--- a/clientapi/routing/directory.go
+++ b/clientapi/routing/directory.go
@@ -47,7 +47,7 @@ func DirectoryRoom(
 	federation *gomatrixserverlib.FederationClient,
 	cfg *config.Dendrite,
 	rsAPI roomserverAPI.RoomserverAliasAPI,
-	fedSenderAPI federationSenderAPI.FederationSenderQueryAPI,
+	fedSenderAPI federationSenderAPI.FederationSenderInternalAPI,
 ) util.JSONResponse {
 	_, domain, err := gomatrixserverlib.SplitID('#', roomAlias)
 	if err != nil {
diff --git a/clientapi/routing/routing.go b/clientapi/routing/routing.go
index 5dc6d7db..9ab22cbe 100644
--- a/clientapi/routing/routing.go
+++ b/clientapi/routing/routing.go
@@ -60,7 +60,7 @@ func Setup(
 	syncProducer *producers.SyncAPIProducer,
 	eduProducer *producers.EDUServerProducer,
 	transactionsCache *transactions.Cache,
-	federationSender federationSenderAPI.FederationSenderQueryAPI,
+	federationSender federationSenderAPI.FederationSenderInternalAPI,
 ) {
 
 	apiMux.Handle("/_matrix/client/versions",
diff --git a/cmd/dendrite-client-api-server/main.go b/cmd/dendrite-client-api-server/main.go
index 815a978a..c8f62968 100644
--- a/cmd/dendrite-client-api-server/main.go
+++ b/cmd/dendrite-client-api-server/main.go
@@ -37,12 +37,12 @@ func main() {
 
 	asQuery := base.CreateHTTPAppServiceAPIs()
 	alias, input, query := base.CreateHTTPRoomserverAPIs()
-	fedSenderAPI := base.CreateHTTPFederationSenderAPIs()
+	fsAPI := base.CreateHTTPFederationSenderAPIs()
 	eduInputAPI := eduserver.SetupEDUServerComponent(base, cache.New())
 
 	clientapi.SetupClientAPIComponent(
 		base, deviceDB, accountDB, federation, &keyRing,
-		alias, input, query, eduInputAPI, asQuery, transactions.New(), fedSenderAPI,
+		alias, input, query, eduInputAPI, asQuery, transactions.New(), fsAPI,
 	)
 
 	base.SetupAndServeHTTP(string(base.Cfg.Bind.ClientAPI), string(base.Cfg.Listen.ClientAPI))
diff --git a/cmd/dendrite-demo-libp2p/main.go b/cmd/dendrite-demo-libp2p/main.go
index 66d103ea..b9fbfc53 100644
--- a/cmd/dendrite-demo-libp2p/main.go
+++ b/cmd/dendrite-demo-libp2p/main.go
@@ -153,15 +153,15 @@ func main() {
 	asQuery := appservice.SetupAppServiceAPIComponent(
 		&base.Base, accountDB, deviceDB, federation, alias, query, transactions.New(),
 	)
-	fedSenderAPI := federationsender.SetupFederationSenderComponent(&base.Base, federation, query, input)
+	fsAPI := federationsender.SetupFederationSenderComponent(&base.Base, federation, query, input)
 
 	clientapi.SetupClientAPIComponent(
 		&base.Base, deviceDB, accountDB,
 		federation, &keyRing, alias, input, query,
-		eduInputAPI, asQuery, transactions.New(), fedSenderAPI,
+		eduInputAPI, asQuery, transactions.New(), fsAPI,
 	)
 	eduProducer := producers.NewEDUServerProducer(eduInputAPI)
-	federationapi.SetupFederationAPIComponent(&base.Base, accountDB, deviceDB, federation, &keyRing, alias, input, query, asQuery, fedSenderAPI, eduProducer)
+	federationapi.SetupFederationAPIComponent(&base.Base, accountDB, deviceDB, federation, &keyRing, alias, input, query, asQuery, fsAPI, eduProducer)
 	mediaapi.SetupMediaAPIComponent(&base.Base, deviceDB)
 	publicRoomsDB, err := storage.NewPublicRoomsServerDatabaseWithPubSub(string(base.Base.Cfg.Database.PublicRoomsAPI), base.LibP2PPubsub)
 	if err != nil {
diff --git a/cmd/dendrite-federation-api-server/main.go b/cmd/dendrite-federation-api-server/main.go
index dd06cd3f..4267cf16 100644
--- a/cmd/dendrite-federation-api-server/main.go
+++ b/cmd/dendrite-federation-api-server/main.go
@@ -32,7 +32,7 @@ func main() {
 	deviceDB := base.CreateDeviceDB()
 	keyDB := base.CreateKeyDB()
 	federation := base.CreateFederationClient()
-	federationSender := base.CreateHTTPFederationSenderAPIs()
+	fsAPI := base.CreateHTTPFederationSenderAPIs()
 	keyRing := keydb.CreateKeyRing(federation.Client, keyDB, cfg.Matrix.KeyPerspectives)
 
 	alias, input, query := base.CreateHTTPRoomserverAPIs()
@@ -42,7 +42,7 @@ func main() {
 
 	federationapi.SetupFederationAPIComponent(
 		base, accountDB, deviceDB, federation, &keyRing,
-		alias, input, query, asQuery, federationSender, eduProducer,
+		alias, input, query, asQuery, fsAPI, eduProducer,
 	)
 
 	base.SetupAndServeHTTP(string(base.Cfg.Bind.FederationAPI), string(base.Cfg.Listen.FederationAPI))
diff --git a/cmd/dendrite-monolith-server/main.go b/cmd/dendrite-monolith-server/main.go
index f3e720a8..e806f6f3 100644
--- a/cmd/dendrite-monolith-server/main.go
+++ b/cmd/dendrite-monolith-server/main.go
@@ -62,15 +62,16 @@ func main() {
 	asQuery := appservice.SetupAppServiceAPIComponent(
 		base, accountDB, deviceDB, federation, alias, query, transactions.New(),
 	)
-	fedSenderAPI := federationsender.SetupFederationSenderComponent(base, federation, query, input)
+	fsAPI := federationsender.SetupFederationSenderComponent(base, federation, query, input)
+	input.SetFederationSenderAPI(fsAPI)
 
 	clientapi.SetupClientAPIComponent(
 		base, deviceDB, accountDB,
 		federation, &keyRing, alias, input, query,
-		eduInputAPI, asQuery, transactions.New(), fedSenderAPI,
+		eduInputAPI, asQuery, transactions.New(), fsAPI,
 	)
 	eduProducer := producers.NewEDUServerProducer(eduInputAPI)
-	federationapi.SetupFederationAPIComponent(base, accountDB, deviceDB, federation, &keyRing, alias, input, query, asQuery, fedSenderAPI, eduProducer)
+	federationapi.SetupFederationAPIComponent(base, accountDB, deviceDB, federation, &keyRing, alias, input, query, asQuery, fsAPI, eduProducer)
 	mediaapi.SetupMediaAPIComponent(base, deviceDB)
 	publicRoomsDB, err := storage.NewPublicRoomsServerDatabase(string(base.Cfg.Database.PublicRoomsAPI))
 	if err != nil {
diff --git a/cmd/dendrite-room-server/main.go b/cmd/dendrite-room-server/main.go
index 98410452..3f9913e2 100644
--- a/cmd/dendrite-room-server/main.go
+++ b/cmd/dendrite-room-server/main.go
@@ -30,7 +30,9 @@ func main() {
 	federation := base.CreateFederationClient()
 	keyRing := keydb.CreateKeyRing(federation.Client, keyDB, cfg.Matrix.KeyPerspectives)
 
-	roomserver.SetupRoomServerComponent(base, keyRing, federation)
+	fsAPI := base.CreateHTTPFederationSenderAPIs()
+	_, input, _ := roomserver.SetupRoomServerComponent(base, keyRing, federation)
+	input.SetFederationSenderAPI(fsAPI)
 
 	base.SetupAndServeHTTP(string(base.Cfg.Bind.RoomServer), string(base.Cfg.Listen.RoomServer))
 
diff --git a/cmd/dendritejs/main.go b/cmd/dendritejs/main.go
index 6300d249..7665138e 100644
--- a/cmd/dendritejs/main.go
+++ b/cmd/dendritejs/main.go
@@ -129,6 +129,7 @@ func main() {
 		base, accountDB, deviceDB, federation, alias, query, transactions.New(),
 	)
 	fedSenderAPI := federationsender.SetupFederationSenderComponent(base, federation, query, input)
+	input.SetFederationSenderAPI(fedSenderAPI)
 
 	clientapi.SetupClientAPIComponent(
 		base, deviceDB, accountDB,
diff --git a/common/basecomponent/base.go b/common/basecomponent/base.go
index 5e2d659b..f245dd50 100644
--- a/common/basecomponent/base.go
+++ b/common/basecomponent/base.go
@@ -149,12 +149,12 @@ func (b *BaseDendrite) CreateHTTPEDUServerAPIs() eduServerAPI.EDUServerInputAPI
 	return e
 }
 
-// CreateHTTPFederationSenderAPIs returns FederationSenderQueryAPI for hitting
+// CreateHTTPFederationSenderAPIs returns FederationSenderInternalAPI for hitting
 // the federation sender over HTTP
-func (b *BaseDendrite) CreateHTTPFederationSenderAPIs() federationSenderAPI.FederationSenderQueryAPI {
-	f, err := federationSenderAPI.NewFederationSenderQueryAPIHTTP(b.Cfg.FederationSenderURL(), b.httpClient)
+func (b *BaseDendrite) CreateHTTPFederationSenderAPIs() federationSenderAPI.FederationSenderInternalAPI {
+	f, err := federationSenderAPI.NewFederationSenderInternalAPIHTTP(b.Cfg.FederationSenderURL(), b.httpClient)
 	if err != nil {
-		logrus.WithError(err).Panic("NewFederationSenderQueryAPIHTTP failed", b.httpClient)
+		logrus.WithError(err).Panic("NewFederationSenderInternalAPIHTTP failed", b.httpClient)
 	}
 	return f
 }
diff --git a/federationapi/federationapi.go b/federationapi/federationapi.go
index ed96322b..72e2b54a 100644
--- a/federationapi/federationapi.go
+++ b/federationapi/federationapi.go
@@ -40,7 +40,7 @@ func SetupFederationAPIComponent(
 	inputAPI roomserverAPI.RoomserverInputAPI,
 	queryAPI roomserverAPI.RoomserverQueryAPI,
 	asAPI appserviceAPI.AppServiceQueryAPI,
-	federationSenderAPI federationSenderAPI.FederationSenderQueryAPI,
+	federationSenderAPI federationSenderAPI.FederationSenderInternalAPI,
 	eduProducer *producers.EDUServerProducer,
 ) {
 	roomserverProducer := producers.NewRoomserverProducer(inputAPI, queryAPI)
diff --git a/federationapi/routing/query.go b/federationapi/routing/query.go
index 7cb50e52..13c92451 100644
--- a/federationapi/routing/query.go
+++ b/federationapi/routing/query.go
@@ -33,7 +33,7 @@ func RoomAliasToID(
 	federation *gomatrixserverlib.FederationClient,
 	cfg *config.Dendrite,
 	aliasAPI roomserverAPI.RoomserverAliasAPI,
-	senderAPI federationSenderAPI.FederationSenderQueryAPI,
+	senderAPI federationSenderAPI.FederationSenderInternalAPI,
 ) util.JSONResponse {
 	roomAlias := httpReq.FormValue("room_alias")
 	if roomAlias == "" {
diff --git a/federationapi/routing/routing.go b/federationapi/routing/routing.go
index 83bac555..ebaeec6e 100644
--- a/federationapi/routing/routing.go
+++ b/federationapi/routing/routing.go
@@ -49,7 +49,7 @@ func Setup(
 	asAPI appserviceAPI.AppServiceQueryAPI,
 	producer *producers.RoomserverProducer,
 	eduProducer *producers.EDUServerProducer,
-	federationSenderAPI federationSenderAPI.FederationSenderQueryAPI,
+	federationSenderAPI federationSenderAPI.FederationSenderInternalAPI,
 	keys gomatrixserverlib.KeyRing,
 	federation *gomatrixserverlib.FederationClient,
 	accountDB accounts.Database,
diff --git a/federationsender/api/api.go b/federationsender/api/api.go
new file mode 100644
index 00000000..1340179e
--- /dev/null
+++ b/federationsender/api/api.go
@@ -0,0 +1,53 @@
+package api
+
+import (
+	"context"
+	"errors"
+	"net/http"
+)
+
+// FederationSenderInternalAPI is used to query information from the federation sender.
+type FederationSenderInternalAPI interface {
+	// Query the joined hosts and the membership events accounting for their participation in a room.
+	// Note that if a server has multiple users in the room, it will have multiple entries in the returned slice.
+	// See `QueryJoinedHostServerNamesInRoom` for a de-duplicated version.
+	QueryJoinedHostsInRoom(
+		ctx context.Context,
+		request *QueryJoinedHostsInRoomRequest,
+		response *QueryJoinedHostsInRoomResponse,
+	) error
+	// Query the server names of the joined hosts in a room.
+	// Unlike QueryJoinedHostsInRoom, this function returns a de-duplicated slice
+	// containing only the server names (without information for membership events).
+	QueryJoinedHostServerNamesInRoom(
+		ctx context.Context,
+		request *QueryJoinedHostServerNamesInRoomRequest,
+		response *QueryJoinedHostServerNamesInRoomResponse,
+	) error
+	// Handle an instruction to make_join & send_join with a remote server.
+	PerformJoinRequest(
+		ctx context.Context,
+		request *PerformJoinRequest,
+		response *PerformJoinResponse,
+	) error
+	// Handle an instruction to make_leave & send_leave with a remote server.
+	PerformLeaveRequest(
+		ctx context.Context,
+		request *PerformLeaveRequest,
+		response *PerformLeaveResponse,
+	) error
+}
+
+// NewFederationSenderInternalAPIHTTP creates a FederationSenderInternalAPI implemented by talking to a HTTP POST API.
+// If httpClient is nil an error is returned
+func NewFederationSenderInternalAPIHTTP(federationSenderURL string, httpClient *http.Client) (FederationSenderInternalAPI, error) {
+	if httpClient == nil {
+		return nil, errors.New("NewFederationSenderInternalAPIHTTP: httpClient is <nil>")
+	}
+	return &httpFederationSenderInternalAPI{federationSenderURL, httpClient}, nil
+}
+
+type httpFederationSenderInternalAPI struct {
+	federationSenderURL string
+	httpClient          *http.Client
+}
diff --git a/federationsender/api/perform.go b/federationsender/api/perform.go
new file mode 100644
index 00000000..8c30ecbe
--- /dev/null
+++ b/federationsender/api/perform.go
@@ -0,0 +1,56 @@
+package api
+
+import (
+	"context"
+
+	commonHTTP "github.com/matrix-org/dendrite/common/http"
+	"github.com/opentracing/opentracing-go"
+)
+
+const (
+	// FederationSenderPerformJoinRequestPath is the HTTP path for the PerformJoinRequest API.
+	FederationSenderPerformJoinRequestPath = "/api/federationsender/performJoinRequest"
+
+	// FederationSenderPerformLeaveRequestPath is the HTTP path for the PerformLeaveRequest API.
+	FederationSenderPerformLeaveRequestPath = "/api/federationsender/performLeaveRequest"
+)
+
+type PerformJoinRequest struct {
+	RoomID string `json:"room_id"`
+}
+
+type PerformJoinResponse struct {
+}
+
+// Handle an instruction to make_join & send_join with a remote server.
+func (h *httpFederationSenderInternalAPI) PerformJoinRequest(
+	ctx context.Context,
+	request *PerformJoinRequest,
+	response *PerformJoinResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "PerformJoinRequest")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderPerformJoinRequestPath
+	return commonHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
+
+type PerformLeaveRequest struct {
+	RoomID string `json:"room_id"`
+}
+
+type PerformLeaveResponse struct {
+}
+
+// Handle an instruction to make_leave & send_leave with a remote server.
+func (h *httpFederationSenderInternalAPI) PerformLeaveRequest(
+	ctx context.Context,
+	request *PerformLeaveRequest,
+	response *PerformLeaveResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "PerformLeaveRequest")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderPerformLeaveRequestPath
+	return commonHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
diff --git a/federationsender/api/query.go b/federationsender/api/query.go
index 7c0ca7ff..7a58cc86 100644
--- a/federationsender/api/query.go
+++ b/federationsender/api/query.go
@@ -2,78 +2,32 @@ package api
 
 import (
 	"context"
-	"errors"
-	"net/http"
 
 	commonHTTP "github.com/matrix-org/dendrite/common/http"
+	"github.com/matrix-org/dendrite/federationsender/types"
 	"github.com/matrix-org/gomatrixserverlib"
 
-	"github.com/matrix-org/dendrite/federationsender/types"
 	"github.com/opentracing/opentracing-go"
 )
 
-// QueryJoinedHostsInRoomRequest is a request to QueryJoinedHostsInRoom
-type QueryJoinedHostsInRoomRequest struct {
-	RoomID string `json:"room_id"`
-}
-
-// QueryJoinedHostsInRoomResponse is a response to QueryJoinedHostsInRoom
-type QueryJoinedHostsInRoomResponse struct {
-	JoinedHosts []types.JoinedHost `json:"joined_hosts"`
-}
-
-// QueryJoinedHostServerNamesRequest is a request to QueryJoinedHostServerNames
-type QueryJoinedHostServerNamesInRoomRequest struct {
-	RoomID string `json:"room_id"`
-}
-
-// QueryJoinedHostServerNamesResponse is a response to QueryJoinedHostServerNames
-type QueryJoinedHostServerNamesInRoomResponse struct {
-	ServerNames []gomatrixserverlib.ServerName `json:"server_names"`
-}
-
-// FederationSenderQueryAPI is used to query information from the federation sender.
-type FederationSenderQueryAPI interface {
-	// Query the joined hosts and the membership events accounting for their participation in a room.
-	// Note that if a server has multiple users in the room, it will have multiple entries in the returned slice.
-	// See `QueryJoinedHostServerNamesInRoom` for a de-duplicated version.
-	QueryJoinedHostsInRoom(
-		ctx context.Context,
-		request *QueryJoinedHostsInRoomRequest,
-		response *QueryJoinedHostsInRoomResponse,
-	) error
-	// Query the server names of the joined hosts in a room.
-	// Unlike QueryJoinedHostsInRoom, this function returns a de-duplicated slice
-	// containing only the server names (without information for membership events).
-	QueryJoinedHostServerNamesInRoom(
-		ctx context.Context,
-		request *QueryJoinedHostServerNamesInRoomRequest,
-		response *QueryJoinedHostServerNamesInRoomResponse,
-	) error
-}
-
 // FederationSenderQueryJoinedHostsInRoomPath is the HTTP path for the QueryJoinedHostsInRoom API.
 const FederationSenderQueryJoinedHostsInRoomPath = "/api/federationsender/queryJoinedHostsInRoom"
 
 // FederationSenderQueryJoinedHostServerNamesInRoomPath is the HTTP path for the QueryJoinedHostServerNamesInRoom API.
 const FederationSenderQueryJoinedHostServerNamesInRoomPath = "/api/federationsender/queryJoinedHostServerNamesInRoom"
 
-// NewFederationSenderQueryAPIHTTP creates a FederationSenderQueryAPI implemented by talking to a HTTP POST API.
-// If httpClient is nil an error is returned
-func NewFederationSenderQueryAPIHTTP(federationSenderURL string, httpClient *http.Client) (FederationSenderQueryAPI, error) {
-	if httpClient == nil {
-		return nil, errors.New("NewFederationSenderQueryAPIHTTP: httpClient is <nil>")
-	}
-	return &httpFederationSenderQueryAPI{federationSenderURL, httpClient}, nil
+// QueryJoinedHostsInRoomRequest is a request to QueryJoinedHostsInRoom
+type QueryJoinedHostsInRoomRequest struct {
+	RoomID string `json:"room_id"`
 }
 
-type httpFederationSenderQueryAPI struct {
-	federationSenderURL string
-	httpClient          *http.Client
+// QueryJoinedHostsInRoomResponse is a response to QueryJoinedHostsInRoom
+type QueryJoinedHostsInRoomResponse struct {
+	JoinedHosts []types.JoinedHost `json:"joined_hosts"`
 }
 
-// QueryJoinedHostsInRoom implements FederationSenderQueryAPI
-func (h *httpFederationSenderQueryAPI) QueryJoinedHostsInRoom(
+// QueryJoinedHostsInRoom implements FederationSenderInternalAPI
+func (h *httpFederationSenderInternalAPI) QueryJoinedHostsInRoom(
 	ctx context.Context,
 	request *QueryJoinedHostsInRoomRequest,
 	response *QueryJoinedHostsInRoomResponse,
@@ -85,8 +39,18 @@ func (h *httpFederationSenderQueryAPI) QueryJoinedHostsInRoom(
 	return commonHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
 }
 
-// QueryJoinedHostServerNamesInRoom implements FederationSenderQueryAPI
-func (h *httpFederationSenderQueryAPI) QueryJoinedHostServerNamesInRoom(
+// QueryJoinedHostServerNamesRequest is a request to QueryJoinedHostServerNames
+type QueryJoinedHostServerNamesInRoomRequest struct {
+	RoomID string `json:"room_id"`
+}
+
+// QueryJoinedHostServerNamesResponse is a response to QueryJoinedHostServerNames
+type QueryJoinedHostServerNamesInRoomResponse struct {
+	ServerNames []gomatrixserverlib.ServerName `json:"server_names"`
+}
+
+// QueryJoinedHostServerNamesInRoom implements FederationSenderInternalAPI
+func (h *httpFederationSenderInternalAPI) QueryJoinedHostServerNamesInRoom(
 	ctx context.Context,
 	request *QueryJoinedHostServerNamesInRoomRequest,
 	response *QueryJoinedHostServerNamesInRoomResponse,
diff --git a/federationsender/federationsender.go b/federationsender/federationsender.go
index a06caf40..355775f8 100644
--- a/federationsender/federationsender.go
+++ b/federationsender/federationsender.go
@@ -36,7 +36,7 @@ func SetupFederationSenderComponent(
 	federation *gomatrixserverlib.FederationClient,
 	rsQueryAPI roomserverAPI.RoomserverQueryAPI,
 	rsInputAPI roomserverAPI.RoomserverInputAPI,
-) api.FederationSenderQueryAPI {
+) api.FederationSenderInternalAPI {
 	federationSenderDB, err := storage.NewDatabase(string(base.Cfg.Database.FederationSender))
 	if err != nil {
 		logrus.WithError(err).Panic("failed to connect to federation sender db")
@@ -61,7 +61,7 @@ func SetupFederationSenderComponent(
 		logrus.WithError(err).Panic("failed to start typing server consumer")
 	}
 
-	queryAPI := query.FederationSenderQueryAPI{
+	queryAPI := query.FederationSenderInternalAPI{
 		DB: federationSenderDB,
 	}
 	queryAPI.SetupHTTP(http.DefaultServeMux)
diff --git a/federationsender/query/api.go b/federationsender/query/api.go
new file mode 100644
index 00000000..e33bcc11
--- /dev/null
+++ b/federationsender/query/api.go
@@ -0,0 +1,77 @@
+package query
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/matrix-org/dendrite/common"
+	"github.com/matrix-org/dendrite/federationsender/api"
+	"github.com/matrix-org/dendrite/federationsender/storage"
+	rsAPI "github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/util"
+)
+
+// FederationSenderInternalAPI is an implementation of api.FederationSenderInternalAPI
+type FederationSenderInternalAPI struct {
+	api.FederationSenderInternalAPI
+	DB                 storage.Database
+	RoomserverInputAPI rsAPI.RoomserverInputAPI
+}
+
+// SetupHTTP adds the FederationSenderInternalAPI handlers to the http.ServeMux.
+func (f *FederationSenderInternalAPI) SetupHTTP(servMux *http.ServeMux) {
+	servMux.Handle(
+		api.FederationSenderQueryJoinedHostsInRoomPath,
+		common.MakeInternalAPI("QueryJoinedHostsInRoom", func(req *http.Request) util.JSONResponse {
+			var request api.QueryJoinedHostsInRoomRequest
+			var response api.QueryJoinedHostsInRoomResponse
+			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
+				return util.ErrorResponse(err)
+			}
+			if err := f.QueryJoinedHostsInRoom(req.Context(), &request, &response); err != nil {
+				return util.ErrorResponse(err)
+			}
+			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
+		}),
+	)
+	servMux.Handle(
+		api.FederationSenderQueryJoinedHostServerNamesInRoomPath,
+		common.MakeInternalAPI("QueryJoinedHostServerNamesInRoom", func(req *http.Request) util.JSONResponse {
+			var request api.QueryJoinedHostServerNamesInRoomRequest
+			var response api.QueryJoinedHostServerNamesInRoomResponse
+			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
+				return util.ErrorResponse(err)
+			}
+			if err := f.QueryJoinedHostServerNamesInRoom(req.Context(), &request, &response); err != nil {
+				return util.ErrorResponse(err)
+			}
+			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
+		}),
+	)
+	servMux.Handle(api.FederationSenderPerformJoinRequestPath,
+		common.MakeInternalAPI("PerformJoinRequest", func(req *http.Request) util.JSONResponse {
+			var request api.PerformJoinRequest
+			var response api.PerformJoinResponse
+			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
+				return util.MessageResponse(http.StatusBadRequest, err.Error())
+			}
+			if err := f.PerformJoinRequest(req.Context(), &request, &response); err != nil {
+				return util.ErrorResponse(err)
+			}
+			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
+		}),
+	)
+	servMux.Handle(api.FederationSenderPerformLeaveRequestPath,
+		common.MakeInternalAPI("PerformLeaveRequest", func(req *http.Request) util.JSONResponse {
+			var request api.PerformLeaveRequest
+			var response api.PerformLeaveResponse
+			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
+				return util.MessageResponse(http.StatusBadRequest, err.Error())
+			}
+			if err := f.PerformLeaveRequest(req.Context(), &request, &response); err != nil {
+				return util.ErrorResponse(err)
+			}
+			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
+		}),
+	)
+}
diff --git a/federationsender/query/perform.go b/federationsender/query/perform.go
new file mode 100644
index 00000000..2486873c
--- /dev/null
+++ b/federationsender/query/perform.go
@@ -0,0 +1,25 @@
+package query
+
+import (
+	"context"
+
+	"github.com/matrix-org/dendrite/federationsender/api"
+)
+
+// PerformJoinRequest implements api.FederationSenderInternalAPI
+func (r *FederationSenderInternalAPI) PerformJoinRequest(
+	ctx context.Context,
+	request *api.PerformJoinRequest,
+	response *api.PerformJoinResponse,
+) (err error) {
+	return nil
+}
+
+// PerformLeaveRequest implements api.FederationSenderInternalAPI
+func (r *FederationSenderInternalAPI) PerformLeaveRequest(
+	ctx context.Context,
+	request *api.PerformLeaveRequest,
+	response *api.PerformLeaveResponse,
+) (err error) {
+	return nil
+}
diff --git a/federationsender/query/query.go b/federationsender/query/query.go
index 8c35bb29..ec668204 100644
--- a/federationsender/query/query.go
+++ b/federationsender/query/query.go
@@ -2,30 +2,13 @@ package query
 
 import (
 	"context"
-	"encoding/json"
-	"net/http"
 
-	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/federationsender/api"
-	"github.com/matrix-org/dendrite/federationsender/types"
 	"github.com/matrix-org/gomatrixserverlib"
-	"github.com/matrix-org/util"
 )
 
-// FederationSenderQueryDatabase has the APIs needed to implement the query API.
-type FederationSenderQueryDatabase interface {
-	GetJoinedHosts(
-		ctx context.Context, roomID string,
-	) ([]types.JoinedHost, error)
-}
-
-// FederationSenderQueryAPI is an implementation of api.FederationSenderQueryAPI
-type FederationSenderQueryAPI struct {
-	DB FederationSenderQueryDatabase
-}
-
-// QueryJoinedHostsInRoom implements api.FederationSenderQueryAPI
-func (f *FederationSenderQueryAPI) QueryJoinedHostsInRoom(
+// QueryJoinedHostsInRoom implements api.FederationSenderInternalAPI
+func (f *FederationSenderInternalAPI) QueryJoinedHostsInRoom(
 	ctx context.Context,
 	request *api.QueryJoinedHostsInRoomRequest,
 	response *api.QueryJoinedHostsInRoomResponse,
@@ -34,8 +17,8 @@ func (f *FederationSenderQueryAPI) QueryJoinedHostsInRoom(
 	return
 }
 
-// QueryJoinedHostServerNamesInRoom implements api.FederationSenderQueryAPI
-func (f *FederationSenderQueryAPI) QueryJoinedHostServerNamesInRoom(
+// QueryJoinedHostServerNamesInRoom implements api.FederationSenderInternalAPI
+func (f *FederationSenderInternalAPI) QueryJoinedHostServerNamesInRoom(
 	ctx context.Context,
 	request *api.QueryJoinedHostServerNamesInRoomRequest,
 	response *api.QueryJoinedHostServerNamesInRoomResponse,
@@ -54,35 +37,3 @@ func (f *FederationSenderQueryAPI) QueryJoinedHostServerNamesInRoom(
 
 	return
 }
-
-// SetupHTTP adds the FederationSenderQueryAPI handlers to the http.ServeMux.
-func (f *FederationSenderQueryAPI) SetupHTTP(servMux *http.ServeMux) {
-	servMux.Handle(
-		api.FederationSenderQueryJoinedHostsInRoomPath,
-		common.MakeInternalAPI("QueryJoinedHostsInRoom", func(req *http.Request) util.JSONResponse {
-			var request api.QueryJoinedHostsInRoomRequest
-			var response api.QueryJoinedHostsInRoomResponse
-			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
-				return util.ErrorResponse(err)
-			}
-			if err := f.QueryJoinedHostsInRoom(req.Context(), &request, &response); err != nil {
-				return util.ErrorResponse(err)
-			}
-			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
-		}),
-	)
-	servMux.Handle(
-		api.FederationSenderQueryJoinedHostServerNamesInRoomPath,
-		common.MakeInternalAPI("QueryJoinedHostServerNamesInRoom", func(req *http.Request) util.JSONResponse {
-			var request api.QueryJoinedHostServerNamesInRoomRequest
-			var response api.QueryJoinedHostServerNamesInRoomResponse
-			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
-				return util.ErrorResponse(err)
-			}
-			if err := f.QueryJoinedHostServerNamesInRoom(req.Context(), &request, &response); err != nil {
-				return util.ErrorResponse(err)
-			}
-			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
-		}),
-	)
-}
diff --git a/roomserver/api/input.go b/roomserver/api/input.go
index bb4e040d..d9cffad2 100644
--- a/roomserver/api/input.go
+++ b/roomserver/api/input.go
@@ -21,6 +21,7 @@ import (
 	"net/http"
 
 	commonHTTP "github.com/matrix-org/dendrite/common/http"
+	fsAPI "github.com/matrix-org/dendrite/federationsender/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	opentracing "github.com/opentracing/opentracing-go"
 )
@@ -106,6 +107,9 @@ type InputRoomEventsResponse struct {
 
 // RoomserverInputAPI is used to write events to the room server.
 type RoomserverInputAPI interface {
+	// needed to avoid chicken and egg scenario when setting up the
+	// interdependencies between the roomserver and the FS input API
+	SetFederationSenderAPI(fsInputAPI fsAPI.FederationSenderInternalAPI)
 	InputRoomEvents(
 		ctx context.Context,
 		request *InputRoomEventsRequest,
@@ -122,12 +126,22 @@ func NewRoomserverInputAPIHTTP(roomserverURL string, httpClient *http.Client) (R
 	if httpClient == nil {
 		return nil, errors.New("NewRoomserverInputAPIHTTP: httpClient is <nil>")
 	}
-	return &httpRoomserverInputAPI{roomserverURL, httpClient}, nil
+	return &httpRoomserverInputAPI{roomserverURL, httpClient, nil}, nil
 }
 
 type httpRoomserverInputAPI struct {
 	roomserverURL string
 	httpClient    *http.Client
+	// The federation sender API allows us to send federation
+	// requests from the new perform input requests, still TODO.
+	fsInputAPI fsAPI.FederationSenderInternalAPI
+}
+
+// SetFederationSenderInputAPI passes in a federation sender input API reference
+// so that we can avoid the chicken-and-egg problem of both the roomserver input API
+// and the federation sender input API being interdependent.
+func (h *httpRoomserverInputAPI) SetFederationSenderAPI(fsInputAPI fsAPI.FederationSenderInternalAPI) {
+	h.fsInputAPI = fsInputAPI
 }
 
 // InputRoomEvents implements RoomserverInputAPI
diff --git a/roomserver/input/input.go b/roomserver/input/input.go
index cb588380..20b6afc4 100644
--- a/roomserver/input/input.go
+++ b/roomserver/input/input.go
@@ -26,6 +26,8 @@ import (
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/storage"
 	"github.com/matrix-org/util"
+
+	fsAPI "github.com/matrix-org/dendrite/federationsender/api"
 )
 
 // RoomserverInputAPI implements api.RoomserverInputAPI
@@ -37,6 +39,16 @@ type RoomserverInputAPI struct {
 	OutputRoomEventTopic string
 	// Protects calls to processRoomEvent
 	mutex sync.Mutex
+	// The federation sender API allows us to send federation
+	// requests from the new perform input requests, still TODO.
+	fsAPI fsAPI.FederationSenderInternalAPI
+}
+
+// SetFederationSenderInputAPI passes in a federation sender input API reference
+// so that we can avoid the chicken-and-egg problem of both the roomserver input API
+// and the federation sender input API being interdependent.
+func (r *RoomserverInputAPI) SetFederationSenderAPI(fsAPI fsAPI.FederationSenderInternalAPI) {
+	r.fsAPI = fsAPI
 }
 
 // WriteOutputEvents implements OutputRoomEventWriter
diff --git a/roomserver/roomserver.go b/roomserver/roomserver.go
index f6a373a4..6fb2caff 100644
--- a/roomserver/roomserver.go
+++ b/roomserver/roomserver.go
@@ -21,6 +21,7 @@ import (
 	"github.com/matrix-org/gomatrixserverlib"
 
 	asQuery "github.com/matrix-org/dendrite/appservice/query"
+
 	"github.com/matrix-org/dendrite/common/basecomponent"
 	"github.com/matrix-org/dendrite/roomserver/alias"
 	"github.com/matrix-org/dendrite/roomserver/input"