2 * Copyright (c) 2010-2023 Contributors to the openHAB project
4 * See the NOTICE file(s) distributed with this work for additional
7 * This program and the accompanying materials are made available under the
8 * terms of the Eclipse Public License 2.0 which is available at
9 * http://www.eclipse.org/legal/epl-2.0
11 * SPDX-License-Identifier: EPL-2.0
13 package org.openhab.binding.nest.internal.sdm.api;
15 import static org.eclipse.jetty.http.HttpHeader.*;
16 import static org.eclipse.jetty.http.HttpMethod.POST;
17 import static org.openhab.binding.nest.internal.sdm.dto.SDMGson.GSON;
19 import java.io.IOException;
20 import java.time.Duration;
21 import java.util.HashMap;
22 import java.util.HashSet;
23 import java.util.List;
26 import java.util.concurrent.ExecutionException;
27 import java.util.concurrent.ScheduledThreadPoolExecutor;
28 import java.util.concurrent.TimeUnit;
29 import java.util.concurrent.TimeoutException;
30 import java.util.function.Consumer;
31 import java.util.stream.Collectors;
33 import org.eclipse.jdt.annotation.NonNullByDefault;
34 import org.eclipse.jetty.client.HttpClient;
35 import org.eclipse.jetty.client.util.StringContentProvider;
36 import org.eclipse.jetty.http.HttpMethod;
37 import org.openhab.binding.nest.internal.sdm.dto.PubSubRequestsResponses.PubSubAcknowledgeRequest;
38 import org.openhab.binding.nest.internal.sdm.dto.PubSubRequestsResponses.PubSubCreateRequest;
39 import org.openhab.binding.nest.internal.sdm.dto.PubSubRequestsResponses.PubSubPullRequest;
40 import org.openhab.binding.nest.internal.sdm.dto.PubSubRequestsResponses.PubSubPullResponse;
41 import org.openhab.binding.nest.internal.sdm.exception.FailedSendingPubSubDataException;
42 import org.openhab.binding.nest.internal.sdm.exception.InvalidPubSubAccessTokenException;
43 import org.openhab.binding.nest.internal.sdm.exception.InvalidPubSubAuthorizationCodeException;
44 import org.openhab.binding.nest.internal.sdm.listener.PubSubSubscriptionListener;
45 import org.openhab.core.auth.client.oauth2.AccessTokenResponse;
46 import org.openhab.core.auth.client.oauth2.OAuthClientService;
47 import org.openhab.core.auth.client.oauth2.OAuthException;
48 import org.openhab.core.auth.client.oauth2.OAuthFactory;
49 import org.openhab.core.auth.client.oauth2.OAuthResponseException;
50 import org.openhab.core.common.NamedThreadFactory;
51 import org.openhab.core.io.net.http.HttpClientFactory;
52 import org.slf4j.Logger;
53 import org.slf4j.LoggerFactory;
56 * The {@link PubSubAPI} implements a subset of the Pub/Sub REST API which allows for subscribing to SDM events.
58 * @author Wouter Born - Initial contribution
60 * @see https://cloud.google.com/pubsub/docs/reference/rest
61 * @see https://developers.google.com/nest/device-access/api/events
64 public class PubSubAPI {
66 private class Subscriber implements Runnable {
68 private final String subscriptionId;
70 Subscriber(String subscriptionId) {
71 this.subscriptionId = subscriptionId;
76 if (!subscriptionListeners.containsKey(subscriptionId)) {
77 logger.debug("Stop receiving subscription '{}' messages since there are no listeners", subscriptionId);
82 checkAccessTokenValidity();
83 String messages = pullSubscriptionMessages(subscriptionId);
85 PubSubPullResponse pullResponse = GSON.fromJson(messages, PubSubPullResponse.class);
87 if (pullResponse != null && pullResponse.receivedMessages != null) {
88 logger.debug("Subscription '{}' has {} new message(s)", subscriptionId,
89 pullResponse.receivedMessages.size());
90 forEachListener(listener -> pullResponse.receivedMessages
91 .forEach(message -> listener.onMessage(message.message)));
92 List<String> ackIds = pullResponse.receivedMessages.stream().map(message -> message.ackId)
93 .collect(Collectors.toList());
94 acknowledgeSubscriptionMessages(subscriptionId, ackIds);
96 forEachListener(PubSubSubscriptionListener::onNoNewMessages);
99 scheduler.submit(this);
100 } catch (FailedSendingPubSubDataException e) {
101 logger.debug("Expected exception while pulling message for '{}' subscription", subscriptionId, e);
102 Throwable cause = e.getCause();
103 if (!(cause instanceof InterruptedException)) {
104 forEachListener(listener -> listener.onError(e));
105 scheduler.schedule(this, RETRY_TIMEOUT.toNanos(), TimeUnit.NANOSECONDS);
107 } catch (InvalidPubSubAccessTokenException e) {
108 logger.warn("Cannot pull messages for '{}' subscription (access or refresh token invalid)",
110 forEachListener(listener -> listener.onError(e));
111 } catch (Exception e) {
112 logger.warn("Unexpected exception while pulling message for '{}' subscription", subscriptionId, e);
113 forEachListener(listener -> listener.onError(e));
114 scheduler.schedule(this, RETRY_TIMEOUT.toNanos(), TimeUnit.NANOSECONDS);
118 private void forEachListener(Consumer<PubSubSubscriptionListener> consumer) {
119 Set<PubSubSubscriptionListener> listeners = subscriptionListeners.get(subscriptionId);
120 if (listeners != null) {
121 listeners.forEach(consumer::accept);
123 logger.debug("Subscription '{}' has no listeners", subscriptionId);
128 private static final String AUTH_URL = "https://accounts.google.com/o/oauth2/auth";
129 private static final String TOKEN_URL = "https://accounts.google.com/o/oauth2/token";
130 private static final String REDIRECT_URI = "https://www.google.com";
132 private static final String PUBSUB_HANDLE_FORMAT = "%s.pubsub";
133 private static final String PUBSUB_SCOPE = "https://www.googleapis.com/auth/pubsub";
135 private static final String PUBSUB_URL_PREFIX = "https://pubsub.googleapis.com/v1/";
136 private static final int PUBSUB_PULL_MAX_MESSAGES = 10;
138 private static final String APPLICATION_JSON = "application/json";
139 private static final String BEARER = "Bearer ";
141 private static final Duration REQUEST_TIMEOUT = Duration.ofMinutes(1);
142 private static final Duration RETRY_TIMEOUT = Duration.ofSeconds(30);
144 private final Logger logger = LoggerFactory.getLogger(PubSubAPI.class);
146 private final HttpClient httpClient;
147 private final OAuthFactory oAuthFactory;
148 private final OAuthClientService oAuthService;
149 private final String oAuthServiceHandleId;
150 private final String projectId;
151 private final ScheduledThreadPoolExecutor scheduler;
152 private final Map<String, Set<PubSubSubscriptionListener>> subscriptionListeners = new HashMap<>();
154 public PubSubAPI(HttpClientFactory httpClientFactory, OAuthFactory oAuthFactory, String ownerId, String projectId,
155 String clientId, String clientSecret) {
156 this.httpClient = httpClientFactory.getCommonHttpClient();
157 this.projectId = projectId;
158 this.oAuthFactory = oAuthFactory;
159 this.oAuthServiceHandleId = String.format(PUBSUB_HANDLE_FORMAT, ownerId);
160 this.oAuthService = oAuthFactory.createOAuthClientService(oAuthServiceHandleId, TOKEN_URL, AUTH_URL, clientId,
161 clientSecret, PUBSUB_SCOPE, false);
162 scheduler = new ScheduledThreadPoolExecutor(3, new NamedThreadFactory(ownerId, true));
165 public void dispose() {
166 subscriptionListeners.clear();
167 scheduler.shutdownNow();
168 oAuthFactory.ungetOAuthService(oAuthServiceHandleId);
171 public void deleteOAuthServiceAndAccessToken() {
172 oAuthFactory.deleteServiceAndAccessToken(oAuthServiceHandleId);
175 public void authorizeClient(String authorizationCode) throws InvalidPubSubAuthorizationCodeException, IOException {
177 oAuthService.getAccessTokenResponseByAuthorizationCode(authorizationCode, REDIRECT_URI);
178 } catch (OAuthException | OAuthResponseException e) {
179 throw new InvalidPubSubAuthorizationCodeException(
180 "Failed to authorize Pub/Sub client. Check the authorization code or generate a new one.", e);
184 public void checkAccessTokenValidity() throws InvalidPubSubAccessTokenException, IOException {
185 getAuthorizationHeader();
188 private String acknowledgeSubscriptionMessages(String subscriptionId, List<String> ackIds)
189 throws FailedSendingPubSubDataException, InvalidPubSubAccessTokenException {
190 logger.debug("Acknowleding {} message(s) for '{}' subscription", ackIds.size(), subscriptionId);
191 String url = getSubscriptionUrl(subscriptionId) + ":acknowledge";
192 String requestContent = GSON.toJson(new PubSubAcknowledgeRequest(ackIds));
193 return postJson(url, requestContent);
196 public void addSubscriptionListener(String subscriptionId, PubSubSubscriptionListener listener) {
197 synchronized (subscriptionListeners) {
198 Set<PubSubSubscriptionListener> listeners = subscriptionListeners.get(subscriptionId);
199 if (listeners == null) {
200 listeners = new HashSet<>();
201 subscriptionListeners.put(subscriptionId, listeners);
203 listeners.add(listener);
204 if (listeners.size() == 1) {
205 scheduler.submit(new Subscriber(subscriptionId));
210 public void removeSubscriptionListener(String subscriptionId, PubSubSubscriptionListener listener) {
211 synchronized (subscriptionListeners) {
212 Set<PubSubSubscriptionListener> listeners = subscriptionListeners.get(subscriptionId);
213 if (listeners != null) {
214 listeners.remove(listener);
215 if (listeners.isEmpty()) {
216 subscriptionListeners.remove(subscriptionId);
217 scheduler.getQueue().removeIf(runnable -> runnable instanceof Subscriber
218 && ((Subscriber) runnable).subscriptionId.equals(subscriptionId));
224 public void createSubscription(String subscriptionId, String topicName)
225 throws FailedSendingPubSubDataException, InvalidPubSubAccessTokenException {
226 logger.debug("Creating '{}' subscription", subscriptionId);
227 String url = getSubscriptionUrl(subscriptionId);
228 String requestContent = GSON.toJson(new PubSubCreateRequest(topicName, true));
229 putJson(url, requestContent);
232 private String getAuthorizationHeader() throws InvalidPubSubAccessTokenException, IOException {
234 AccessTokenResponse response = oAuthService.getAccessTokenResponse();
235 if (response == null || response.getAccessToken() == null || response.getAccessToken().isEmpty()) {
236 throw new InvalidPubSubAccessTokenException(
237 "No Pub/Sub access token. Client may not have been authorized.");
239 if (response.getRefreshToken() == null || response.getRefreshToken().isEmpty()) {
240 throw new InvalidPubSubAccessTokenException(
241 "No Pub/Sub refresh token. Delete and readd credentials, then reauthorize.");
243 return BEARER + response.getAccessToken();
244 } catch (OAuthException | OAuthResponseException e) {
245 throw new InvalidPubSubAccessTokenException(
246 "Error fetching Pub/Sub access token. Check the authorization code or generate a new one.", e);
250 private String getSubscriptionUrl(String subscriptionId) {
251 return PUBSUB_URL_PREFIX + "projects/" + projectId + "/subscriptions/" + subscriptionId;
254 private String postJson(String url, String requestContent)
255 throws FailedSendingPubSubDataException, InvalidPubSubAccessTokenException {
257 logger.debug("Posting JSON to: {}", url);
258 String response = httpClient.newRequest(url) //
260 .header(ACCEPT, APPLICATION_JSON) //
261 .header(AUTHORIZATION, getAuthorizationHeader()) //
262 .content(new StringContentProvider(requestContent), APPLICATION_JSON) //
263 .timeout(REQUEST_TIMEOUT.toNanos(), TimeUnit.NANOSECONDS) //
265 .getContentAsString();
266 logger.debug("Response: {}", response);
268 } catch (ExecutionException | InterruptedException | IOException | TimeoutException e) {
269 throw new FailedSendingPubSubDataException("Failed to send JSON POST request", e);
273 private String pullSubscriptionMessages(String subscriptionId)
274 throws FailedSendingPubSubDataException, InvalidPubSubAccessTokenException {
275 logger.debug("Pulling messages for '{}' subscription", subscriptionId);
276 String url = getSubscriptionUrl(subscriptionId) + ":pull";
277 String requestContent = GSON.toJson(new PubSubPullRequest(PUBSUB_PULL_MAX_MESSAGES));
278 return postJson(url, requestContent);
281 private String putJson(String url, String requestContent)
282 throws FailedSendingPubSubDataException, InvalidPubSubAccessTokenException {
284 logger.debug("Putting JSON to: {}", url);
285 String response = httpClient.newRequest(url) //
286 .method(HttpMethod.PUT) //
287 .header(ACCEPT, APPLICATION_JSON) //
288 .header(AUTHORIZATION, getAuthorizationHeader()) //
289 .content(new StringContentProvider(requestContent), APPLICATION_JSON) //
290 .timeout(REQUEST_TIMEOUT.toNanos(), TimeUnit.NANOSECONDS) //
292 .getContentAsString();
293 logger.debug("Response: {}", response);
295 } catch (ExecutionException | InterruptedException | IOException | TimeoutException e) {
296 throw new FailedSendingPubSubDataException("Failed to send JSON PUT request", e);