Refactor how federationsender gets created (#1095)

* Refactor how federationsender gets created

* s/httpint/inthttp/ for alphabetical niceness with internal package

federationsender/inthttp/client.go

@@ -0,0 +1,113 @@
+package inthttp
+
+import (
+	"context"
+	"errors"
+	"net/http"
+
+	"github.com/matrix-org/dendrite/federationsender/api"
+	internalHTTP "github.com/matrix-org/dendrite/internal/http"
+	"github.com/opentracing/opentracing-go"
+)
+
+// HTTP paths for the internal HTTP API
+const (
+	FederationSenderQueryJoinedHostsInRoomPath           = "/federationsender/queryJoinedHostsInRoom"
+	FederationSenderQueryJoinedHostServerNamesInRoomPath = "/federationsender/queryJoinedHostServerNamesInRoom"
+
+	FederationSenderPerformDirectoryLookupRequestPath = "/federationsender/performDirectoryLookup"
+	FederationSenderPerformJoinRequestPath            = "/federationsender/performJoinRequest"
+	FederationSenderPerformLeaveRequestPath           = "/federationsender/performLeaveRequest"
+	FederationSenderPerformServersAlivePath           = "/federationsender/performServersAlive"
+)
+
+// NewFederationSenderClient creates a FederationSenderInternalAPI implemented by talking to a HTTP POST API.
+// If httpClient is nil an error is returned
+func NewFederationSenderClient(federationSenderURL string, httpClient *http.Client) (api.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
+}
+
+// Handle an instruction to make_leave & send_leave with a remote server.
+func (h *httpFederationSenderInternalAPI) PerformLeave(
+	ctx context.Context,
+	request *api.PerformLeaveRequest,
+	response *api.PerformLeaveResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "PerformLeaveRequest")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderPerformLeaveRequestPath
+	return internalHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
+
+func (h *httpFederationSenderInternalAPI) PerformServersAlive(
+	ctx context.Context,
+	request *api.PerformServersAliveRequest,
+	response *api.PerformServersAliveResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "PerformServersAlive")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderPerformServersAlivePath
+	return internalHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
+
+// QueryJoinedHostServerNamesInRoom implements FederationSenderInternalAPI
+func (h *httpFederationSenderInternalAPI) QueryJoinedHostServerNamesInRoom(
+	ctx context.Context,
+	request *api.QueryJoinedHostServerNamesInRoomRequest,
+	response *api.QueryJoinedHostServerNamesInRoomResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "QueryJoinedHostServerNamesInRoom")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderQueryJoinedHostServerNamesInRoomPath
+	return internalHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
+
+// QueryJoinedHostsInRoom implements FederationSenderInternalAPI
+func (h *httpFederationSenderInternalAPI) QueryJoinedHostsInRoom(
+	ctx context.Context,
+	request *api.QueryJoinedHostsInRoomRequest,
+	response *api.QueryJoinedHostsInRoomResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "QueryJoinedHostsInRoom")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderQueryJoinedHostsInRoomPath
+	return internalHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
+
+// Handle an instruction to make_join & send_join with a remote server.
+func (h *httpFederationSenderInternalAPI) PerformJoin(
+	ctx context.Context,
+	request *api.PerformJoinRequest,
+	response *api.PerformJoinResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "PerformJoinRequest")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderPerformJoinRequestPath
+	return internalHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}
+
+// Handle an instruction to make_join & send_join with a remote server.
+func (h *httpFederationSenderInternalAPI) PerformDirectoryLookup(
+	ctx context.Context,
+	request *api.PerformDirectoryLookupRequest,
+	response *api.PerformDirectoryLookupResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "PerformDirectoryLookup")
+	defer span.Finish()
+
+	apiURL := h.federationSenderURL + FederationSenderPerformDirectoryLookupRequestPath
+	return internalHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}