use go module for dependencies (#594)

roomserver/types/types.go

@@ -0,0 +1,203 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package types provides the types that are used internally within the roomserver.
+package types
+
+import (
+	"github.com/matrix-org/dendrite/common"
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+// EventTypeNID is a numeric ID for an event type.
+type EventTypeNID int64
+
+// EventStateKeyNID is a numeric ID for an event state_key.
+type EventStateKeyNID int64
+
+// EventNID is a numeric ID for an event.
+type EventNID int64
+
+// RoomNID is a numeric ID for a room.
+type RoomNID int64
+
+// StateSnapshotNID is a numeric ID for the state at an event.
+type StateSnapshotNID int64
+
+// StateBlockNID is a numeric ID for a block of state data.
+// These blocks of state data are combined to form the actual state.
+type StateBlockNID int64
+
+// A StateKeyTuple is a pair of a numeric event type and a numeric state key.
+// It is used to lookup state entries.
+type StateKeyTuple struct {
+	// The numeric ID for the event type.
+	EventTypeNID EventTypeNID
+	// The numeric ID for the state key.
+	EventStateKeyNID EventStateKeyNID
+}
+
+// LessThan returns true if this state key is less than the other state key.
+// The ordering is arbitrary and is used to implement binary search and to efficiently deduplicate entries.
+func (a StateKeyTuple) LessThan(b StateKeyTuple) bool {
+	if a.EventTypeNID != b.EventTypeNID {
+		return a.EventTypeNID < b.EventTypeNID
+	}
+	return a.EventStateKeyNID < b.EventStateKeyNID
+}
+
+// A StateEntry is an entry in the room state of a matrix room.
+type StateEntry struct {
+	StateKeyTuple
+	// The numeric ID for the event.
+	EventNID EventNID
+}
+
+// LessThan returns true if this state entry is less than the other state entry.
+// The ordering is arbitrary and is used to implement binary search and to efficiently deduplicate entries.
+func (a StateEntry) LessThan(b StateEntry) bool {
+	if a.StateKeyTuple != b.StateKeyTuple {
+		return a.StateKeyTuple.LessThan(b.StateKeyTuple)
+	}
+	return a.EventNID < b.EventNID
+}
+
+// StateAtEvent is the state before and after a matrix event.
+type StateAtEvent struct {
+	// The state before the event.
+	BeforeStateSnapshotNID StateSnapshotNID
+	// The state entry for the event itself, allows us to calculate the state after the event.
+	StateEntry
+}
+
+// IsStateEvent returns whether the event the state is at is a state event.
+func (s StateAtEvent) IsStateEvent() bool {
+	return s.EventStateKeyNID != 0
+}
+
+// StateAtEventAndReference is StateAtEvent and gomatrixserverlib.EventReference glued together.
+// It is used when looking up the latest events in a room in the database.
+// The gomatrixserverlib.EventReference is used to check whether a new event references the event.
+// The StateAtEvent is used to construct the current state of the room from the latest events.
+type StateAtEventAndReference struct {
+	StateAtEvent
+	gomatrixserverlib.EventReference
+}
+
+// An Event is a gomatrixserverlib.Event with the numeric event ID attached.
+// It is when performing bulk event lookup in the database.
+type Event struct {
+	EventNID EventNID
+	gomatrixserverlib.Event
+}
+
+const (
+	// MRoomCreateNID is the numeric ID for the "m.room.create" event type.
+	MRoomCreateNID = 1
+	// MRoomPowerLevelsNID is the numeric ID for the "m.room.power_levels" event type.
+	MRoomPowerLevelsNID = 2
+	// MRoomJoinRulesNID is the numeric ID for the "m.room.join_rules" event type.
+	MRoomJoinRulesNID = 3
+	// MRoomThirdPartyInviteNID is the numeric ID for the "m.room.third_party_invite" event type.
+	MRoomThirdPartyInviteNID = 4
+	// MRoomMemberNID is the numeric ID for the "m.room.member" event type.
+	MRoomMemberNID = 5
+	// MRoomRedactionNID is the numeric ID for the "m.room.redaction" event type.
+	MRoomRedactionNID = 6
+	// MRoomHistoryVisibilityNID is the numeric ID for the "m.room.history_visibility" event type.
+	MRoomHistoryVisibilityNID = 7
+)
+
+const (
+	// EmptyStateKeyNID is the numeric ID for the empty state key.
+	EmptyStateKeyNID = 1
+)
+
+// StateBlockNIDList is used to return the result of bulk StateBlockNID lookups from the database.
+type StateBlockNIDList struct {
+	StateSnapshotNID StateSnapshotNID
+	StateBlockNIDs   []StateBlockNID
+}
+
+// StateEntryList is used to return the result of bulk state entry lookups from the database.
+type StateEntryList struct {
+	StateBlockNID StateBlockNID
+	StateEntries  []StateEntry
+}
+
+// A RoomRecentEventsUpdater is used to update the recent events in a room.
+// (On postgresql this wraps a database transaction that holds a "FOR UPDATE"
+//  lock on the row in the rooms table holding the latest events for the room.)
+type RoomRecentEventsUpdater interface {
+	// The latest event IDs and state in the room.
+	LatestEvents() []StateAtEventAndReference
+	// The event ID of the latest event written to the output log in the room.
+	LastEventIDSent() string
+	// The current state of the room.
+	CurrentStateSnapshotNID() StateSnapshotNID
+	// Store the previous events referenced by an event.
+	// This adds the event NID to an entry in the database for each of the previous events.
+	// If there isn't an entry for one of previous events then an entry is created.
+	// If the entry already lists the event NID as a referrer then the entry unmodified.
+	// (i.e. the operation is idempotent)
+	StorePreviousEvents(eventNID EventNID, previousEventReferences []gomatrixserverlib.EventReference) error
+	// Check whether the eventReference is already referenced by another matrix event.
+	IsReferenced(eventReference gomatrixserverlib.EventReference) (bool, error)
+	// Set the list of latest events for the room.
+	// This replaces the current list stored in the database with the given list
+	SetLatestEvents(
+		roomNID RoomNID, latest []StateAtEventAndReference, lastEventNIDSent EventNID,
+		currentStateSnapshotNID StateSnapshotNID,
+	) error
+	// Check if the event has already be written to the output logs.
+	HasEventBeenSent(eventNID EventNID) (bool, error)
+	// Mark the event as having been sent to the output logs.
+	MarkEventAsSent(eventNID EventNID) error
+	// Build a membership updater for the target user in this room.
+	// It will share the same transaction as this updater.
+	MembershipUpdater(targetUserNID EventStateKeyNID) (MembershipUpdater, error)
+	// Implements Transaction so it can be committed or rolledback
+	common.Transaction
+}
+
+// A MembershipUpdater is used to update the membership of a user in a room.
+// (On postgresql this wraps a database transaction that holds a "FOR UPDATE"
+//  lock on the row in the membership table for this user in the room)
+// The caller should call one of SetToInvite, SetToJoin or SetToLeave once to
+// make the update, or none of them if no update is required.
+type MembershipUpdater interface {
+	// True if the target user is invited to the room before updating.
+	IsInvite() bool
+	// True if the target user is joined to the room before updating.
+	IsJoin() bool
+	// True if the target user is not invited or joined to the room before updating.
+	IsLeave() bool
+	// Set the state to invite.
+	// Returns whether this invite needs to be sent
+	SetToInvite(event gomatrixserverlib.Event) (needsSending bool, err error)
+	// Set the state to join or updates the event ID in the database.
+	// Returns a list of invite event IDs that this state change retired.
+	SetToJoin(senderUserID string, eventID string, isUpdate bool) (inviteEventIDs []string, err error)
+	// Set the state to leave.
+	// Returns a list of invite event IDs that this state change retired.
+	SetToLeave(senderUserID string, eventID string) (inviteEventIDs []string, err error)
+	// Implements Transaction so it can be committed or rolledback.
+	common.Transaction
+}
+
+// A MissingEventError is an error that happened because the roomserver was
+// missing requested events from its database.
+type MissingEventError string
+
+func (e MissingEventError) Error() string { return string(e) }