aboutsummaryrefslogtreecommitdiff
path: root/federationapi/routing/state.go
blob: fa0e9351ea47579f384815e6e69cc7fba49b14e6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
// 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 routing

import (
	"context"
	"net/http"
	"net/url"

	"github.com/matrix-org/dendrite/roomserver/api"
	"github.com/matrix-org/dendrite/roomserver/types"
	"github.com/matrix-org/gomatrixserverlib/fclient"
	"github.com/matrix-org/gomatrixserverlib/spec"
	"github.com/matrix-org/util"
)

// GetState returns state events & auth events for the roomID, eventID
func GetState(
	ctx context.Context,
	request *fclient.FederationRequest,
	rsAPI api.FederationRoomserverAPI,
	roomID string,
) util.JSONResponse {
	eventID, err := parseEventIDParam(request)
	if err != nil {
		return *err
	}

	stateEvents, authChain, err := getState(ctx, request, rsAPI, roomID, eventID)
	if err != nil {
		return *err
	}

	return util.JSONResponse{Code: http.StatusOK, JSON: &fclient.RespState{
		AuthEvents:  types.NewEventJSONsFromHeaderedEvents(authChain),
		StateEvents: types.NewEventJSONsFromHeaderedEvents(stateEvents),
	}}
}

// GetStateIDs returns state event IDs & auth event IDs for the roomID, eventID
func GetStateIDs(
	ctx context.Context,
	request *fclient.FederationRequest,
	rsAPI api.FederationRoomserverAPI,
	roomID string,
) util.JSONResponse {
	eventID, err := parseEventIDParam(request)
	if err != nil {
		return *err
	}

	stateEvents, authEvents, err := getState(ctx, request, rsAPI, roomID, eventID)
	if err != nil {
		return *err
	}

	stateEventIDs := getIDsFromEvent(stateEvents)
	authEventIDs := getIDsFromEvent(authEvents)

	return util.JSONResponse{Code: http.StatusOK, JSON: fclient.RespStateIDs{
		StateEventIDs: stateEventIDs,
		AuthEventIDs:  authEventIDs,
	},
	}
}

func parseEventIDParam(
	request *fclient.FederationRequest,
) (eventID string, resErr *util.JSONResponse) {
	URL, err := url.Parse(request.RequestURI())
	if err != nil {
		response := util.ErrorResponse(err)
		resErr = &response
		return
	}

	eventID = URL.Query().Get("event_id")
	if eventID == "" {
		resErr = &util.JSONResponse{
			Code: http.StatusBadRequest,
			JSON: spec.MissingParam("event_id missing"),
		}
	}

	return
}

func getState(
	ctx context.Context,
	request *fclient.FederationRequest,
	rsAPI api.FederationRoomserverAPI,
	roomID string,
	eventID string,
) (stateEvents, authEvents []*types.HeaderedEvent, errRes *util.JSONResponse) {
	// If we don't think we belong to this room then don't waste the effort
	// responding to expensive requests for it.
	if err := ErrorIfLocalServerNotInRoom(ctx, rsAPI, roomID); err != nil {
		return nil, nil, err
	}

	event, resErr := fetchEvent(ctx, rsAPI, roomID, eventID)
	if resErr != nil {
		return nil, nil, resErr
	}

	if event.RoomID() != roomID {
		return nil, nil, &util.JSONResponse{Code: http.StatusNotFound, JSON: spec.NotFound("event does not belong to this room")}
	}
	resErr = allowedToSeeEvent(ctx, request.Origin(), rsAPI, eventID)
	if resErr != nil {
		return nil, nil, resErr
	}

	var response api.QueryStateAndAuthChainResponse
	err := rsAPI.QueryStateAndAuthChain(
		ctx,
		&api.QueryStateAndAuthChainRequest{
			RoomID:       roomID,
			PrevEventIDs: []string{eventID},
			AuthEventIDs: event.AuthEventIDs(),
		},
		&response,
	)
	if err != nil {
		resErr := util.ErrorResponse(err)
		return nil, nil, &resErr
	}

	switch {
	case !response.RoomExists:
		return nil, nil, &util.JSONResponse{
			Code: http.StatusNotFound,
			JSON: spec.NotFound("Room not found"),
		}
	case !response.StateKnown:
		return nil, nil, &util.JSONResponse{
			Code: http.StatusNotFound,
			JSON: spec.NotFound("State not known"),
		}
	case response.IsRejected:
		return nil, nil, &util.JSONResponse{
			Code: http.StatusNotFound,
			JSON: spec.NotFound("Event not found"),
		}
	}

	return response.StateEvents, response.AuthChainEvents, nil
}

func getIDsFromEvent(events []*types.HeaderedEvent) []string {
	IDs := make([]string, len(events))
	for i := range events {
		IDs[i] = events[i].EventID()
	}

	return IDs
}