Line data Source code
1 : /*
2 : *
3 : * Copyright (c) 2021 Project CHIP Authors
4 : * All rights reserved.
5 : *
6 : * Licensed under the Apache License, Version 2.0 (the "License");
7 : * you may not use this file except in compliance with the License.
8 : * You may obtain a copy of the License at
9 : *
10 : * http://www.apache.org/licenses/LICENSE-2.0
11 : *
12 : * Unless required by applicable law or agreed to in writing, software
13 : * distributed under the License is distributed on an "AS IS" BASIS,
14 : * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 : * See the License for the specific language governing permissions and
16 : * limitations under the License.
17 : */
18 :
19 : /**
20 : * @file
21 : * This file defines read client for a CHIP Interaction Data model
22 : *
23 : */
24 :
25 : #pragma once
26 : #include "system/SystemClock.h"
27 : #include <app/AppConfig.h>
28 : #include <app/AttributePathParams.h>
29 : #include <app/ConcreteAttributePath.h>
30 : #include <app/EventHeader.h>
31 : #include <app/EventPathParams.h>
32 : #include <app/MessageDef/ReadRequestMessage.h>
33 : #include <app/MessageDef/StatusIB.h>
34 : #include <app/MessageDef/StatusResponseMessage.h>
35 : #include <app/MessageDef/SubscribeRequestMessage.h>
36 : #include <app/MessageDef/SubscribeResponseMessage.h>
37 : #include <app/OperationalSessionSetup.h>
38 : #include <app/ReadPrepareParams.h>
39 : #include <app/data-model/Decode.h>
40 : #include <lib/core/CHIPCallback.h>
41 : #include <lib/core/CHIPCore.h>
42 : #include <lib/core/TLVDebug.h>
43 : #include <lib/support/CodeUtils.h>
44 : #include <lib/support/DLLUtil.h>
45 : #include <lib/support/logging/CHIPLogging.h>
46 : #include <messaging/ExchangeContext.h>
47 : #include <messaging/ExchangeHolder.h>
48 : #include <messaging/ExchangeMgr.h>
49 : #include <messaging/Flags.h>
50 : #include <protocols/Protocols.h>
51 : #include <system/SystemPacketBuffer.h>
52 :
53 : #if CHIP_CONFIG_ENABLE_READ_CLIENT
54 : namespace chip {
55 : namespace app {
56 :
57 : class InteractionModelEngine;
58 :
59 : /**
60 : * @class ReadClient
61 : *
62 : * @brief The read client represents the initiator side of a Read Or Subscribe Interaction (depending on the APIs invoked).
63 : *
64 : * When used to manage subscriptions, the client provides functionality to automatically re-subscribe as needed,
65 : * including re-establishing CASE under certain conditions (see Callback::OnResubscriptionNeeded for more info).
66 : * This is the default behavior. A consumer can completely opt-out of this behavior by over-riding
67 : * Callback::OnResubscriptionNeeded and providing an alternative implementation.
68 : *
69 : */
70 : class ReadClient : public Messaging::ExchangeDelegate
71 : {
72 : public:
73 : class Callback
74 : {
75 : public:
76 0 : Callback() = default;
77 :
78 : // Callbacks are not expected to be copyable or movable.
79 : Callback(const Callback &) = delete;
80 : Callback(Callback &&) = delete;
81 : Callback & operator=(const Callback &) = delete;
82 : Callback & operator=(Callback &&) = delete;
83 :
84 0 : virtual ~Callback() = default;
85 :
86 : /**
87 : * Used to notify a (maybe empty) report data is received from peer and the subscription and the peer is alive.
88 : *
89 : * This object MUST continue to exist after this call is completed. The application shall wait until it
90 : * receives an OnDone call to destroy the object.
91 : *
92 : */
93 0 : virtual void NotifySubscriptionStillActive(const ReadClient & apReadClient) {}
94 :
95 : /**
96 : * Used to signal the commencement of processing of the first attribute or event report received in a given exchange.
97 : *
98 : * This object MUST continue to exist after this call is completed. The application shall wait until it
99 : * receives an OnDone call to destroy the object.
100 : *
101 : * Once OnReportBegin has been called, either OnReportEnd or OnError will be called before OnDone.
102 : *
103 : */
104 0 : virtual void OnReportBegin() {}
105 :
106 : /**
107 : * Used to signal the completion of processing of the last attribute or event report in a given exchange.
108 : *
109 : * This object MUST continue to exist after this call is completed. The application shall wait until it
110 : * receives an OnDone call to destroy the object.
111 : *
112 : */
113 0 : virtual void OnReportEnd() {}
114 :
115 : /**
116 : * Used to deliver event data received through the Read and Subscribe interactions
117 : *
118 : * Only one of the apData and apStatus can be non-null.
119 : *
120 : * This object MUST continue to exist after this call is completed. The application shall wait until it
121 : * receives an OnDone call to destroy the object.
122 : *
123 : * @param[in] aEventHeader The event header in report response.
124 : * @param[in] apData A TLVReader positioned right on the payload of the event.
125 : * @param[in] apStatus Event-specific status, containing an InteractionModel::Status code as well as an optional
126 : * cluster-specific status code.
127 : */
128 0 : virtual void OnEventData(const EventHeader & aEventHeader, TLV::TLVReader * apData, const StatusIB * apStatus) {}
129 :
130 : /**
131 : * Used to deliver attribute data received through the Read and Subscribe interactions.
132 : *
133 : * This callback will be called when:
134 : * - Receiving attribute data as response of Read interactions
135 : * - Receiving attribute data as reports of subscriptions
136 : * - Receiving attribute data as initial reports of subscriptions
137 : *
138 : * This object MUST continue to exist after this call is completed. The application shall wait until it
139 : * receives an OnDone call to destroy the object.
140 : *
141 : * @param[in] aPath The attribute path field in report response.
142 : * @param[in] apData The attribute data of the given path, will be a nullptr if status is not Success.
143 : * @param[in] aStatus Attribute-specific status, containing an InteractionModel::Status code as well as an
144 : * optional cluster-specific status code.
145 : */
146 0 : virtual void OnAttributeData(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apData, const StatusIB & aStatus) {}
147 :
148 : /**
149 : * OnSubscriptionEstablished will be called when a subscription is established for the given subscription transaction.
150 : * If using auto resubscription, OnSubscriptionEstablished will be called whenever resubscription is established.
151 : *
152 : * This object MUST continue to exist after this call is completed. The application shall wait until it
153 : * receives an OnDone call to destroy the object.
154 : *
155 : * @param[in] aSubscriptionId The identifier of the subscription that was established.
156 : */
157 0 : virtual void OnSubscriptionEstablished(SubscriptionId aSubscriptionId) {}
158 :
159 : /**
160 : * OnResubscriptionNeeded will be called when a subscription that was started with SendAutoResubscribeRequest has terminated
161 : * and re-subscription is needed. The termination cause is provided to help inform subsequent re-subscription logic.
162 : *
163 : * The base implementation automatically re-subscribes at appropriate intervals taking the termination cause into account
164 : * (see ReadClient::DefaultResubscribePolicy for more details). If the default implementation doesn't suffice, the logic of
165 : * ReadClient::DefaultResubscribePolicy is broken down into its constituent methods that are publicly available for
166 : * applications to call and sequence.
167 : *
168 : * If the peer is LIT ICD, and the timeout is reached, `aTerminationCause` will be
169 : * `CHIP_ERROR_LIT_SUBSCRIBE_INACTIVE_TIMEOUT`. In this case, returning `CHIP_NO_ERROR` will still trigger a resubscribe
170 : * attempt, while returning `CHIP_ERROR_LIT_SUBSCRIBE_INACTIVE_TIMEOUT` will put the subscription in the
171 : * `InactiveICDSubscription` state. In the latter case, OnResubscriptionNeeded will be called again when
172 : * `OnActiveModeNotification` is called.
173 : *
174 : * If the method is over-ridden, it's the application's responsibility to take the appropriate steps needed to eventually
175 : * call-back into the ReadClient object to schedule a re-subscription (by invoking ReadClient::ScheduleResubscription).
176 : *
177 : * If the application DOES NOT want re-subscription to happen on a particular invocation of this method, returning anything
178 : * other than CHIP_NO_ERROR will terminate the interaction and result in OnError, OnDeallocatePaths and OnDone being called
179 : * in that sequence.
180 : *
181 : * This object MUST continue to exist after this call is completed. The
182 : * application shall wait until it receives an OnDone call to destroy the object.
183 : *
184 : * @param[in] aTerminationCause The cause of failure of the subscription that just terminated.
185 : */
186 0 : virtual CHIP_ERROR OnResubscriptionNeeded(ReadClient * apReadClient, CHIP_ERROR aTerminationCause)
187 : {
188 0 : return apReadClient->DefaultResubscribePolicy(aTerminationCause);
189 : }
190 :
191 : /**
192 : * OnError will be called when an error occurs *after* a successful call to SendRequest(). The following
193 : * errors will be delivered through this call in the aError field:
194 : *
195 : * - CHIP_ERROR_TIMEOUT: A response was not received within the expected response timeout.
196 : * - CHIP_ERROR_*TLV*: A malformed, non-compliant response was received from the server.
197 : * - CHIP_ERROR encapsulating a StatusIB: If we got a non-path-specific
198 : * status response from the server. In that case, constructing
199 : * a StatusIB from the error can be used to extract the status.
200 : * - CHIP_ERROR*: All other cases.
201 : *
202 : * This object MUST continue to exist after this call is completed. The application shall wait until it
203 : * receives an OnDone call to destroy the object.
204 : *
205 : * @param[in] aError A system error code that conveys the overall error code.
206 : */
207 0 : virtual void OnError(CHIP_ERROR aError) {}
208 :
209 : /**
210 : * OnDone will be called when ReadClient has finished all work and it is
211 : * safe to destroy and free the allocated ReadClient object and any
212 : * other objects associated with the Read or Subscribe interaction.
213 : *
214 : * This function will:
215 : * - Always be called exactly *once* for a given ReadClient instance.
216 : * - Be called even in error circumstances.
217 : * - Only be called after a successful call to SendRequest has been
218 : * made, when the read completes or the subscription is shut down.
219 : *
220 : * @param[in] apReadClient the ReadClient for the completed interaction.
221 : */
222 : virtual void OnDone(ReadClient * apReadClient) = 0;
223 :
224 : /**
225 : * This function is invoked when using SendAutoResubscribeRequest, where the ReadClient was configured to auto re-subscribe
226 : * and the ReadPrepareParams was moved into this client for management. This will have to be free'ed appropriately by the
227 : * application. If SendAutoResubscribeRequest fails, this function will be called before it returns the failure. If
228 : * SendAutoResubscribeRequest succeeds, this function will be called immediately before calling OnDone, or
229 : * when the ReadClient is destroyed, if that happens before OnDone. If SendAutoResubscribeRequest is not called,
230 : * this function will not be called.
231 : */
232 0 : virtual void OnDeallocatePaths(ReadPrepareParams && aReadPrepareParams) {}
233 :
234 : /**
235 : * This function is invoked when constructing a read/subscribeRequest that does not have data
236 : * version filters specified, to give the callback a chance to provide some.
237 : *
238 : * This function is expected to encode as many complete data version filters as will fit into
239 : * the buffer, rolling back any partially-encoded filters if it runs out of space, and set the
240 : * aEncodedDataVersionList boolean to true if it has successfully encoded at least one data version filter.
241 : *
242 : * Otherwise aEncodedDataVersionList will be set to false.
243 : */
244 0 : virtual CHIP_ERROR OnUpdateDataVersionFilterList(DataVersionFilterIBs::Builder & aDataVersionFilterIBsBuilder,
245 : const Span<AttributePathParams> & aAttributePaths,
246 : bool & aEncodedDataVersionList)
247 : {
248 0 : aEncodedDataVersionList = false;
249 0 : return CHIP_NO_ERROR;
250 : }
251 :
252 : /*
253 : * Get highest received event number.
254 : * If the application does not want to filter events by event number, it should call ClearValue() on aEventNumber
255 : * and return CHIP_NO_ERROR. An error return from this function will fail the entire read client interaction.
256 : */
257 0 : virtual CHIP_ERROR GetHighestReceivedEventNumber(Optional<EventNumber> & aEventNumber)
258 : {
259 0 : aEventNumber.ClearValue();
260 0 : return CHIP_NO_ERROR;
261 : }
262 :
263 : /**
264 : * OnUnsolicitedMessageFromPublisher will be called for a subscription
265 : * ReadClient when any incoming message is received from a matching
266 : * node on the fabric.
267 : *
268 : * This callback will be called:
269 : * - When receiving any unsolicited communication from the node
270 : * - Even for disconnected subscriptions.
271 : *
272 : * Callee MUST not synchronously destroy ReadClients in this callback.
273 : *
274 : * @param[in] apReadClient the ReadClient for the subscription.
275 : */
276 0 : virtual void OnUnsolicitedMessageFromPublisher(ReadClient * apReadClient) {}
277 :
278 : /**
279 : * OnCASESessionEstablished will be called for a subscription ReadClient when
280 : * it finishes setting up a CASE session, as part of either automatic
281 : * re-subscription or doing an initial subscribe based on ScopedNodeId.
282 : *
283 : * The callee is allowed to modify the ReadPrepareParams (e.g. to change
284 : * things like min/max intervals based on the session parameters).
285 : */
286 0 : virtual void OnCASESessionEstablished(const SessionHandle & aSession, ReadPrepareParams & aSubscriptionParams) {}
287 : };
288 :
289 : enum class InteractionType : uint8_t
290 : {
291 : Read,
292 : Subscribe,
293 : };
294 :
295 : enum class PeerType : uint8_t
296 : {
297 : kNormal,
298 : kLITICD,
299 : };
300 :
301 : /**
302 : *
303 : * Constructor.
304 : *
305 : * The callback passed in has to outlive this ReadClient object.
306 : *
307 : * This object can outlive the InteractionModelEngine passed in. However, upon shutdown of the engine,
308 : * this object will cease to function correctly since it depends on the engine for a number of critical functions.
309 : *
310 : * @param[in] apImEngine A valid pointer to the IM engine.
311 : * @param[in] apExchangeMgr A pointer to the ExchangeManager object. Allowed to be null
312 : * if the version of SendAutoResubscribeRequest that takes a
313 : * ScopedNodeId is used.
314 : * @param[in] apCallback Callback set by application.
315 : * @param[in] aInteractionType Type of interaction (read or subscribe)
316 : *
317 : * @retval #CHIP_ERROR_INCORRECT_STATE incorrect state if it is already initialized
318 : * @retval #CHIP_NO_ERROR On success.
319 : *
320 : */
321 : ReadClient(InteractionModelEngine * apImEngine, Messaging::ExchangeManager * apExchangeMgr, Callback & apCallback,
322 : InteractionType aInteractionType);
323 :
324 : /**
325 : * Destructor.
326 : *
327 : * Will abort the exchange context if a valid one still exists. It will also cancel any
328 : * liveness timers that may be active.
329 : *
330 : * OnDone() will not be called.
331 : */
332 : ~ReadClient() override;
333 :
334 : /**
335 : * Send a request. There can be one request outstanding on a given ReadClient.
336 : * If SendRequest returns success, no more SendRequest calls can happen on this ReadClient
337 : * until the corresponding OnDone call has happened.
338 : *
339 : * This will send either a Read Request or a Subscribe Request depending on
340 : * the InteractionType this read client was initialized with.
341 : *
342 : * If the params contain more data version filters than can fit in the request packet
343 : * the list will be truncated as needed, i.e. filter inclusion is on a best effort basis.
344 : *
345 : * @retval #others fail to send read request
346 : * @retval #CHIP_NO_ERROR On success.
347 : */
348 : CHIP_ERROR SendRequest(ReadPrepareParams & aReadPrepareParams);
349 :
350 : /**
351 : * Re-activate an inactive subscription.
352 : *
353 : * When subscribing to LIT-ICD and liveness timeout reached and OnResubscriptionNeeded returns
354 : * CHIP_ERROR_LIT_SUBSCRIBE_INACTIVE_TIMEOUT, the read client will move to the InactiveICDSubscription state and
355 : * resubscription can be triggered via OnActiveModeNotification().
356 : *
357 : * If the subscription is not in the `InactiveICDSubscription` state, this function will do nothing. So it is always safe to
358 : * call this function when a check-in message is received.
359 : */
360 : void OnActiveModeNotification();
361 :
362 : void OnUnsolicitedReportData(Messaging::ExchangeContext * apExchangeContext, System::PacketBufferHandle && aPayload);
363 :
364 195 : void OnUnsolicitedMessageFromPublisher()
365 : {
366 195 : TriggerResubscribeIfScheduled("unsolicited message");
367 :
368 : // Then notify callbacks
369 195 : mpCallback.OnUnsolicitedMessageFromPublisher(this);
370 195 : }
371 :
372 : auto GetSubscriptionId() const
373 : {
374 : using returnType = Optional<decltype(mSubscriptionId)>;
375 : return mInteractionType == InteractionType::Subscribe ? returnType(mSubscriptionId) : returnType::Missing();
376 : }
377 :
378 41 : FabricIndex GetFabricIndex() const { return mPeer.GetFabricIndex(); }
379 71 : NodeId GetPeerNodeId() const { return mPeer.GetNodeId(); }
380 645 : bool IsReadType() { return mInteractionType == InteractionType::Read; }
381 5006 : bool IsSubscriptionType() const { return mInteractionType == InteractionType::Subscribe; };
382 :
383 : /*
384 : * Retrieve the reporting intervals associated with an active subscription. This should only be called if we're of subscription
385 : * interaction type and after a subscription has been established.
386 : */
387 : CHIP_ERROR GetReportingIntervals(uint16_t & aMinIntervalFloorSeconds, uint16_t & aMaxIntervalCeilingSeconds) const
388 : {
389 : VerifyOrReturnError(IsSubscriptionType(), CHIP_ERROR_INCORRECT_STATE);
390 : VerifyOrReturnError(IsSubscriptionActive(), CHIP_ERROR_INCORRECT_STATE);
391 :
392 : aMinIntervalFloorSeconds = mMinIntervalFloorSeconds;
393 : aMaxIntervalCeilingSeconds = mMaxInterval;
394 :
395 : return CHIP_NO_ERROR;
396 : }
397 :
398 161 : ReadClient * GetNextClient() { return mpNext; }
399 154 : void SetNextClient(ReadClient * apClient) { mpNext = apClient; }
400 :
401 : /**
402 : * Like SendSubscribeRequest, but the ReadClient will automatically attempt to re-establish the subscription if
403 : * we decide that the subscription has dropped. The exact behavior of the re-establishment can be controlled
404 : * by setting mResubscribePolicy in the ReadPrepareParams. If not set, a default behavior with exponential backoff will be
405 : * used.
406 : *
407 : * The application has to know to
408 : * a) allocate a ReadPrepareParams object that will have fields mpEventPathParamsList and mpAttributePathParamsList and
409 : * mpDataVersionFilterList with lifetimes as long as the ReadClient itself and b) free those up later in the call to
410 : * OnDeallocatePaths. Note: At a given time in the system, you can either have a single subscription with re-sub enabled that
411 : * has mKeepSubscriptions = false, OR, multiple subs with re-sub enabled with mKeepSubscriptions = true. You shall not
412 : * have a mix of both simultaneously. If SendAutoResubscribeRequest is called at all, it guarantees that it will call
413 : * OnDeallocatePaths (either befor returning error, or when OnDone is called). SendAutoResubscribeRequest is the only case
414 : * that calls OnDeallocatePaths, since that's the only case when the consumer moved a ReadParams into the client.
415 : *
416 : */
417 : CHIP_ERROR SendAutoResubscribeRequest(ReadPrepareParams && aReadPrepareParams);
418 :
419 : /**
420 : * Like SendAutoResubscribeRequest above, but without a session being
421 : * available in the ReadPrepareParams. When this is used, the ReadClient is
422 : * responsible for setting up the CASE session itself.
423 : *
424 : * When using this version of SendAutoResubscribeRequest, any session to
425 : * which ReadPrepareParams has a reference will be ignored.
426 : */
427 : CHIP_ERROR SendAutoResubscribeRequest(const ScopedNodeId & aPublisherId, ReadPrepareParams && aReadPrepareParams);
428 :
429 : /**
430 : * This provides a standard re-subscription policy implementation that given a termination cause, does the following:
431 : * - Calculates the time till next subscription with fibonacci back-off (implemented by ComputeTimeTillNextSubscription()).
432 : * - Schedules the next subscription attempt at the computed interval from the previous step. Operational discovery and
433 : * CASE establishment will be attempted if aTerminationCause was CHIP_ERROR_TIMEOUT. In all other cases, it will attempt
434 : * to re-use a previously established session.
435 : */
436 : CHIP_ERROR DefaultResubscribePolicy(CHIP_ERROR aTerminationCause);
437 :
438 : /**
439 : * Computes the time, in milliseconds, until the next re-subscription over
440 : * an ever increasing window following a fibonacci sequence with the current retry count
441 : * used as input to the fibonacci algorithm.
442 : *
443 : * CHIP_RESUBSCRIBE_MAX_FIBONACCI_STEP_INDEX is the maximum value the retry count can tick up to.
444 : *
445 : */
446 : uint32_t ComputeTimeTillNextSubscription();
447 :
448 : /**
449 : * Schedules a re-subscription aTimeTillNextResubscriptionMs into the future.
450 : *
451 : * If an application wants to set up CASE on their own, they should call ComputeTimeTillNextSubscription() to compute the next
452 : * interval at which they should attempt CASE and attempt CASE at that time. On successful CASE establishment, this method
453 : * should be called with the new SessionHandle provided through 'aNewSessionHandle', 'aTimeTillNextResubscriptionMs' set to 0
454 : * (i.e async, but as soon as possible) and 'aReestablishCASE' set to false.
455 : *
456 : * Otherwise, if aReestablishCASE is true, operational discovery and CASE will be attempted at that time before
457 : * the actual IM interaction is initiated.
458 : *
459 : * aReestablishCASE SHALL NOT be set to true if a valid SessionHandle is provided through newSessionHandle.
460 : */
461 : CHIP_ERROR ScheduleResubscription(uint32_t aTimeTillNextResubscriptionMs, Optional<SessionHandle> aNewSessionHandle,
462 : bool aReestablishCASE);
463 :
464 : // Like SendSubscribeRequest, but allows sending certain forms of invalid
465 : // subscribe requests that servers are expected to reject, for testing
466 : // purposes. Should only be called from tests.
467 : #if CONFIG_BUILD_FOR_HOST_UNIT_TEST
468 : CHIP_ERROR SendSubscribeRequestWithoutValidation(const ReadPrepareParams & aReadPrepareParams)
469 : {
470 : return SendSubscribeRequestImpl(aReadPrepareParams);
471 : }
472 : #endif // CONFIG_BUILD_FOR_HOST_UNIT_TEST
473 :
474 : /**
475 : * Override the interval at which liveness of the subscription is assessed.
476 : * By default, this is set set to the max interval of the subscription + ACK timeout of the underlying session.
477 : *
478 : * This can be only be called once a subscription has been established and is active. Once called, this will cancel any existing
479 : * liveness timers and schedule a new one.
480 : *
481 : * This can be called from the Callback::OnSubscriptionEstablished callback.
482 : *
483 : */
484 : void OverrideLivenessTimeout(System::Clock::Timeout aLivenessTimeout);
485 :
486 : /**
487 : * If the ReadClient currently has a resubscription attempt scheduled,
488 : * trigger that attempt right now. This is generally useful when a consumer
489 : * has some sort of indication that the server side is currently up and
490 : * communicating, so right now is a good time to try to resubscribe.
491 : *
492 : * The reason string is used for logging if a resubscribe is triggered.
493 : */
494 : void TriggerResubscribeIfScheduled(const char * reason);
495 :
496 : /**
497 : * Returns the timeout after which we consider the subscription to have
498 : * dropped, if we have received no messages within that amount of time.
499 : *
500 : * Returns NullOptional if a subscription has not yet been established (and
501 : * hence the MaxInterval is not yet known), or if the subscription session
502 : * is gone and hence the relevant MRP parameters can no longer be determined.
503 : */
504 : Optional<System::Clock::Timeout> GetSubscriptionTimeout();
505 :
506 : private:
507 : friend class TestReadInteraction;
508 : friend class InteractionModelEngine;
509 :
510 : enum class ClientState : uint8_t
511 : {
512 : Idle, ///< The client has been initialized and is ready for a SendRequest
513 : AwaitingInitialReport, ///< The client is waiting for initial report
514 : AwaitingSubscribeResponse, ///< The client is waiting for subscribe response
515 : SubscriptionActive, ///< The client is maintaining subscription
516 : InactiveICDSubscription, ///< The client is waiting to resubscribe for LIT device
517 : };
518 :
519 : enum class ReportType
520 : {
521 : // kUnsolicited reports are the first message in an exchange.
522 : kUnsolicited,
523 : // kContinuingTransaction reports are responses to a message we sent.
524 : kContinuingTransaction
525 : };
526 :
527 608 : bool IsMatchingSubscriptionId(SubscriptionId aSubscriptionId)
528 : {
529 608 : return aSubscriptionId == mSubscriptionId && mInteractionType == InteractionType::Subscribe;
530 : }
531 :
532 : CHIP_ERROR OnMessageReceived(Messaging::ExchangeContext * apExchangeContext, const PayloadHeader & aPayloadHeader,
533 : System::PacketBufferHandle && aPayload) override;
534 : void OnResponseTimeout(Messaging::ExchangeContext * apExchangeContext) override;
535 :
536 : /**
537 : * Updates the type (LIT ICD or not) of the peer.
538 : *
539 : * When the subscription is active, this function will just set the flag. When the subscription is an InactiveICDSubscription,
540 : * setting the peer type to SIT or normal devices will also trigger a resubscription attempt.
541 : *
542 : */
543 : void OnPeerTypeChange(PeerType aType);
544 :
545 : /**
546 : * Check if current read client is being used
547 : *
548 : */
549 2036 : bool IsIdle() const { return mState == ClientState::Idle; }
550 2182 : bool IsInactiveICDSubscription() const { return mState == ClientState::InactiveICDSubscription; }
551 1153 : bool IsSubscriptionActive() const { return mState == ClientState::SubscriptionActive; }
552 696 : bool IsAwaitingInitialReport() const { return mState == ClientState::AwaitingInitialReport; }
553 252 : bool IsAwaitingSubscribeResponse() const { return mState == ClientState::AwaitingSubscribeResponse; }
554 :
555 : CHIP_ERROR GenerateEventPaths(EventPathIBs::Builder & aEventPathsBuilder, const Span<EventPathParams> & aEventPaths);
556 : CHIP_ERROR GenerateAttributePaths(AttributePathIBs::Builder & aAttributePathIBsBuilder,
557 : const Span<AttributePathParams> & aAttributePaths);
558 :
559 : CHIP_ERROR GenerateDataVersionFilterList(DataVersionFilterIBs::Builder & aDataVersionFilterIBsBuilder,
560 : const Span<AttributePathParams> & aAttributePaths,
561 : const Span<DataVersionFilter> & aDataVersionFilters, bool & aEncodedDataVersionList);
562 : CHIP_ERROR BuildDataVersionFilterList(DataVersionFilterIBs::Builder & aDataVersionFilterIBsBuilder,
563 : const Span<AttributePathParams> & aAttributePaths,
564 : const Span<DataVersionFilter> & aDataVersionFilters, bool & aEncodedDataVersionList);
565 : CHIP_ERROR ReadICDOperatingModeFromAttributeDataIB(TLV::TLVReader && aReader, PeerType & aType);
566 : CHIP_ERROR ProcessAttributeReportIBs(TLV::TLVReader & aAttributeDataIBsReader);
567 : CHIP_ERROR ProcessEventReportIBs(TLV::TLVReader & aEventReportIBsReader);
568 :
569 : static void OnLivenessTimeoutCallback(System::Layer * apSystemLayer, void * apAppState);
570 : CHIP_ERROR ProcessSubscribeResponse(System::PacketBufferHandle && aPayload);
571 : CHIP_ERROR RefreshLivenessCheckTimer();
572 : CHIP_ERROR ComputeLivenessCheckTimerTimeout(System::Clock::Timeout * aTimeout);
573 : void CancelLivenessCheckTimer();
574 : void CancelResubscribeTimer();
575 : void TriggerResubscriptionForLivenessTimeout(CHIP_ERROR aReason);
576 : void MoveToState(const ClientState aTargetState);
577 : CHIP_ERROR ProcessAttributePath(AttributePathIB::Parser & aAttributePath, ConcreteDataAttributePath & aClusterInfo);
578 : CHIP_ERROR ProcessReportData(System::PacketBufferHandle && aPayload, ReportType aReportType);
579 : const char * GetStateStr() const;
580 :
581 : /*
582 : * Checks if we should re-subscribe based on the specified re-subscription policy. If we should, re-subscription is scheduled
583 : * aNextResubscribeIntervalMsec is updated accordingly, and true is returned.
584 : *
585 : * If we should not resubscribe, false is returned.
586 : *
587 : * @param[out] aNextResubscribeIntervalMsec How long we will wait before trying to auto-resubscribe.
588 : */
589 : bool ResubscribeIfNeeded(uint32_t & aNextResubscribeIntervalMsec);
590 :
591 : // Specialized request-sending functions.
592 : CHIP_ERROR SendReadRequest(ReadPrepareParams & aReadPrepareParams);
593 : // SendSubscribeRequest performs som validation on aSubscribePrepareParams
594 : // and then calls SendSubscribeRequestImpl.
595 : CHIP_ERROR SendSubscribeRequest(const ReadPrepareParams & aSubscribePrepareParams);
596 : CHIP_ERROR SendSubscribeRequestImpl(const ReadPrepareParams & aSubscribePrepareParams);
597 : void UpdateDataVersionFilters(const ConcreteDataAttributePath & aPath);
598 : static void OnResubscribeTimerCallback(System::Layer * apSystemLayer, void * apAppState);
599 : // Called to ensure OnReportBegin is called before calling OnEventData or OnAttributeData
600 : void NoteReportingData();
601 :
602 : /*
603 : * Called internally to signal the completion of all work on this object, gracefully close the
604 : * exchange and finally, signal to the application that it's
605 : * safe to release this object.
606 : *
607 : * If aError != CHIP_NO_ERROR, this will trigger re-subscriptions if allowResubscription is true
608 : * AND if this ReadClient instance is tracking a subscription AND the applications decides to do so
609 : * in their implementation of Callback::OnResubscriptionNeeded().
610 : */
611 : void Close(CHIP_ERROR aError, bool allowResubscription = true);
612 :
613 : void StopResubscription();
614 : void ClearActiveSubscriptionState();
615 :
616 : static void HandleDeviceConnected(void * context, Messaging::ExchangeManager & exchangeMgr,
617 : const SessionHandle & sessionHandle);
618 : static void HandleDeviceConnectionFailure(void * context, const OperationalSessionSetup::ConnectionFailureInfo & failureInfo);
619 :
620 : CHIP_ERROR GetMinEventNumber(const ReadPrepareParams & aReadPrepareParams, Optional<EventNumber> & aEventMin);
621 :
622 : /**
623 : * Start setting up a CASE session to our peer, if we can locate a
624 : * CASESessionManager. Returns error if we did not even manage to kick off
625 : * a CASE attempt.
626 : */
627 : CHIP_ERROR EstablishSessionToPeer();
628 :
629 : Messaging::ExchangeManager * mpExchangeMgr = nullptr;
630 : Messaging::ExchangeHolder mExchange;
631 : Callback & mpCallback;
632 : ClientState mState = ClientState::Idle;
633 : bool mIsReporting = false;
634 : bool mIsInitialReport = true;
635 : // boolean to check if client is waiting for the first priming report
636 : bool mWaitingForFirstPrimingReport = true;
637 : bool mPendingMoreChunks = false;
638 : uint16_t mMinIntervalFloorSeconds = 0;
639 : uint16_t mMaxInterval = 0;
640 : SubscriptionId mSubscriptionId = 0;
641 : ScopedNodeId mPeer;
642 : InteractionType mInteractionType = InteractionType::Read;
643 : Timestamp mEventTimestamp;
644 :
645 : bool mForceCaseOnNextResub = true;
646 : bool mIsResubscriptionScheduled = false;
647 :
648 : // mMinimalResubscribeDelay is used to store the delay returned with a BUSY
649 : // response to a Sigma1 message.
650 : System::Clock::Milliseconds16 mMinimalResubscribeDelay = System::Clock::kZero;
651 :
652 : chip::Callback::Callback<OnDeviceConnected> mOnConnectedCallback;
653 : chip::Callback::Callback<OperationalSessionSetup::OnSetupFailure> mOnConnectionFailureCallback;
654 :
655 : ReadClient * mpNext = nullptr;
656 : InteractionModelEngine * mpImEngine = nullptr;
657 :
658 : //
659 : // This stores the params associated with the interaction in a specific set of cases:
660 : // 1. Stores all parameters when used with subscriptions initiated using SendAutoResubscribeRequest.
661 : // 2. Stores just the SessionHolder when used with any subscriptions.
662 : //
663 : ReadPrepareParams mReadPrepareParams;
664 : uint32_t mNumRetries = 0;
665 :
666 : System::Clock::Timeout mLivenessTimeoutOverride = System::Clock::kZero;
667 :
668 : bool mIsPeerLIT = false;
669 :
670 : // End Of Container (0x18) uses one byte.
671 : static constexpr uint16_t kReservedSizeForEndOfContainer = 1;
672 : // Reserved size for the uint8_t InteractionModelRevision flag, which takes up 1 byte for the control tag and 1 byte for the
673 : // context tag, 1 byte for value
674 : static constexpr uint16_t kReservedSizeForIMRevision = 1 + 1 + 1;
675 : // Reserved buffer for TLV level overhead (the overhead for data version filter IBs EndOfContainer, IM reversion end
676 : // of RequestMessage (another end of container)).
677 : static constexpr uint16_t kReservedSizeForTLVEncodingOverhead =
678 : kReservedSizeForEndOfContainer + kReservedSizeForIMRevision + kReservedSizeForEndOfContainer;
679 :
680 : #if CHIP_PROGRESS_LOGGING
681 : // Tracks the time when a subscribe request is successfully sent.
682 : // This timestamp allows for logging the duration taken to established the subscription.
683 : System::Clock::Timestamp mSubscribeRequestTime = System::Clock::kZero;
684 : #endif
685 : };
686 :
687 : }; // namespace app
688 : }; // namespace chip
689 : #endif // CHIP_CONFIG_ENABLE_READ_CLIENT
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