-
Notifications
You must be signed in to change notification settings - Fork 285
/
WebsocketGraphQLTransportWSProtocolHandler.kt
198 lines (186 loc) · 10.1 KB
/
WebsocketGraphQLTransportWSProtocolHandler.kt
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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
/*
* Copyright 2021 Netflix, Inc.
*
* 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 com.netflix.graphql.dgs.webflux.handlers
import com.fasterxml.jackson.module.kotlin.convertValue
import com.netflix.graphql.dgs.reactive.DgsReactiveQueryExecutor
import com.netflix.graphql.types.subscription.websockets.CloseCode
import com.netflix.graphql.types.subscription.websockets.Message
import graphql.ExecutionResult
import graphql.GraphqlErrorBuilder
import org.reactivestreams.Publisher
import org.reactivestreams.Subscription
import org.slf4j.LoggerFactory
import org.springframework.core.ResolvableType
import org.springframework.core.io.buffer.DataBuffer
import org.springframework.core.io.buffer.DataBufferUtils
import org.springframework.http.codec.json.Jackson2JsonDecoder
import org.springframework.http.codec.json.Jackson2JsonEncoder
import org.springframework.util.MimeTypeUtils
import org.springframework.web.reactive.socket.CloseStatus
import org.springframework.web.reactive.socket.WebSocketMessage
import org.springframework.web.reactive.socket.WebSocketSession
import reactor.core.publisher.Flux
import reactor.core.publisher.Mono
import java.time.Duration
import java.util.*
import java.util.concurrent.ConcurrentHashMap
class WebsocketGraphQLTransportWSProtocolHandler(private val dgsReactiveQueryExecutor: DgsReactiveQueryExecutor, private val connectionInitTimeout: Duration) : WebsocketReactiveProtocolHandler {
private val resolvableType = ResolvableType.forType(Message::class.java)
private val sessions = ConcurrentHashMap<String, MutableMap<String, Subscription>>()
private val connections = ConcurrentHashMap<String, Boolean>()
private val decoder = Jackson2JsonDecoder()
private val encoder = Jackson2JsonEncoder(decoder.objectMapper)
override fun handle(webSocketSession: WebSocketSession): Mono<Void> {
connections[webSocketSession.id] = false
Mono.delay(connectionInitTimeout).then(
Mono.defer {
if (connections[webSocketSession.id] == false) {
webSocketSession.close(CloseStatus(CloseCode.ConnectionInitialisationTimeout.code, "Did not receive a ConnectionInitMessage"))
} else Mono.empty()
}
)
.subscribe()
return webSocketSession.send(
webSocketSession.receive()
.flatMap outer@{ message ->
val buffer: DataBuffer = DataBufferUtils.retain(message.payload)
val operationMessage: Message = decoder.decode(
buffer,
resolvableType,
MimeTypeUtils.APPLICATION_JSON,
null
) as Message
when (operationMessage) {
is Message.ConnectionInitMessage -> {
if (connections[webSocketSession.id]!!) {
// we've already received a connection request and this must be an error
return@outer webSocketSession.close(CloseStatus(CloseCode.TooManyInitialisationRequests.code, "Too many connection initialisation requests")).thenMany(Mono.empty())
}
connections[webSocketSession.id] = true
Flux.just(
toWebsocketMessage(
Message.ConnectionAckMessage(),
webSocketSession
)
)
}
is Message.SubscribeMessage -> {
val queryPayload = decoder.objectMapper.convertValue<Message.SubscribeMessage.Payload>(
operationMessage.payload
)
if (sessions.containsKey(webSocketSession.id)) {
return@outer webSocketSession.close(CloseStatus(CloseCode.SubscriberAlreadyExists.code, "Subscriber for ${webSocketSession.id} already exists")).thenMany(Mono.empty())
}
logger.debug("Starting subscription {} for session {}", queryPayload, webSocketSession.id)
dgsReactiveQueryExecutor.execute(queryPayload.query, queryPayload.variables)
.flatMapMany { executionResult ->
val publisher: Publisher<ExecutionResult> = executionResult.getData()
Flux.from(publisher).map { er ->
toWebsocketMessage(
Message.NextMessage(
payload = com.netflix.graphql.types.subscription.websockets.ExecutionResult(er.getData(), er.errors),
id = operationMessage.id
),
webSocketSession
)
}.doOnSubscribe {
if (operationMessage.id != null) {
sessions[webSocketSession.id] = mutableMapOf(operationMessage.id to it)
}
}.doOnComplete {
webSocketSession.send(
Flux.just(
toWebsocketMessage(
Message.CompleteMessage(operationMessage.id),
webSocketSession
)
)
).subscribe()
sessions[webSocketSession.id]?.remove(operationMessage.id)
logger.debug(
"Completing subscription {} for connection {}",
operationMessage.id,
webSocketSession.id
)
}.doOnError {
webSocketSession.send(
Flux.just(
toWebsocketMessage(
Message.ErrorMessage(payload = listOf(GraphqlErrorBuilder.newError().message(it.message).build()), id = operationMessage.id),
webSocketSession
)
)
).subscribe()
sessions[webSocketSession.id]?.remove(operationMessage.id)
logger.debug(
"Subscription publisher error for input {} for subscription {} for connection {}",
queryPayload,
operationMessage.id,
webSocketSession.id,
it
)
}
}
}
is Message.PingMessage ->
Flux.just(
toWebsocketMessage(
Message.PongMessage(),
webSocketSession
)
)
is Message.PongMessage -> Flux.empty()
is Message.CompleteMessage -> {
sessions[webSocketSession.id]?.remove(operationMessage.id)?.cancel()
logger.debug(
"Client stopped subscription {} for connection {}",
operationMessage.id,
webSocketSession.id
)
Flux.empty()
}
else -> {
return@outer webSocketSession.close(CloseStatus(CloseCode.BadRequest.code, "Unrecognized message")).thenMany(Mono.empty())
}
}
}
.log()
.doFinally {
logger.debug("Cleaning up subscriptions for session ${webSocketSession.id}")
sessions[webSocketSession.id]?.forEach {
it.value.cancel()
}
sessions.remove(webSocketSession.id)
connections.remove(webSocketSession.id)
}
)
}
private fun toWebsocketMessage(operationMessage: Message, session: WebSocketSession): WebSocketMessage {
return WebSocketMessage(
WebSocketMessage.Type.TEXT,
encoder.encodeValue(
operationMessage,
session.bufferFactory(),
resolvableType,
MimeTypeUtils.APPLICATION_JSON,
null
)
)
}
companion object {
private val logger = LoggerFactory.getLogger(DgsReactiveQueryExecutor::class.java)
}
}