GetEvent implements GET /_matrix/client/r0/rooms/{roomId}/event/{eventId} https://spec.matrix.org/v1.4/client-server-api/#get_matrixclientv3roomsroomideventeventid.

GetFilter implements GET /_matrix/client/r0/user/{userId}/filter/{filterId}.

GetMemberships implements GET /rooms/{roomId}/members.

OnIncomingMessagesRequest implements the /messages endpoint from the client-server API.

PutFilter implements POST /_matrix/client/r0/user/{userId}/filter.

nolint:gocyclo.

nolint:gocyclo.

Setup configures the given mux with sync-server listeners Due to Setup being used to call many other functions, a gocyclo nolint is applied: nolint: gocyclo.