HTTP-Bridge add support for time based subscribes

io.openems.edge.bridge.http/src/io/openems/edge/bridge/http/BridgeHttpImpl.java

@@ -1,9 +1,11 @@
 package io.openems.edge.bridge.http;
 
+import java.util.HashSet;
 import java.util.PriorityQueue;
+import java.util.Set;
 import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
 
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
@@ -23,26 +25,33 @@
 )
 public class BridgeHttpImpl implements BridgeHttp {
 
-	private static class EndpointCountdown {
+	public static class CycleEndpointCountdown {
 		private volatile int cycleCount;
-		public final Endpoint endpoint;
+		public final CycleEndpoint cycleEndpoint;
 		private volatile boolean running = false;
 
-		public EndpointCountdown(Endpoint endpoint) {
-			super();
+		public CycleEndpointCountdown(CycleEndpoint endpoint) {
 			this.cycleCount = endpoint.cycle();
-			this.endpoint = endpoint;
+			this.cycleEndpoint = endpoint;
 		}
 
-		public EndpointCountdown reset() {
-			this.cycleCount = this.endpoint.cycle();
+		/**
+		 * Resets the current cycle count to the initial cycle count.
+		 * 
+		 * @return this
+		 */
+		public CycleEndpointCountdown reset() {
+			this.cycleCount = this.cycleEndpoint.cycle();
 			return this;
 		}
 
 		public int getCycleCount() {
 			return this.cycleCount;
 		}
 
+		/**
+		 * Decreases the current cycle count by one.
+		 */
 		public void decreaseCycleCount() {
 			this.cycleCount--;
 		}
@@ -57,6 +66,53 @@ public void setRunning(boolean running) {
 
 	}
 
+	public static class TimeEndpointCountdown {
+		private final TimeEndpoint timeEndpoint;
+		private volatile boolean running = false;
+		private volatile boolean shutdown = false;
+		private Runnable shutdownCurrentTask;
+
+		public TimeEndpointCountdown(TimeEndpoint timeEndpoint) {
+			this.timeEndpoint = timeEndpoint;
+		}
+
+		public TimeEndpoint getTimeEndpoint() {
+			return this.timeEndpoint;
+		}
+
+		public boolean isRunning() {
+			return this.running;
+		}
+
+		public void setRunning(boolean running) {
+			this.running = running;
+		}
+
+		public boolean isShutdown() {
+			return this.shutdown;
+		}
+
+		public void setShutdown(boolean shutdown) {
+			this.shutdown = shutdown;
+		}
+
+		public void setShutdownCurrentTask(Runnable shutdownCurrentTask) {
+			this.shutdownCurrentTask = shutdownCurrentTask;
+		}
+
+		/**
+		 * Shuts down the current execution of the active task.
+		 */
+		public void shutdown() {
+			this.setShutdown(true);
+			final var shutdownTask = this.shutdownCurrentTask;
+			if (shutdownTask != null) {
+				shutdownTask.run();
+			}
+		}
+
+	}
+
 	private final Logger log = LoggerFactory.getLogger(BridgeHttpImpl.class);
 
 	@Reference
@@ -67,94 +123,155 @@ public void setRunning(boolean running) {
 
 	// TODO change to java 21 virtual threads
 	// TODO: Single pool for every http worker & avoid same endpoint in that pool
-	private final ExecutorService pool = Executors.newCachedThreadPool();
+	private final ScheduledExecutorService pool = Executors.newScheduledThreadPool(0);
 
-	private final PriorityQueue<EndpointCountdown> endpoints = new PriorityQueue<>(
+	private final PriorityQueue<CycleEndpointCountdown> cycleEndpoints = new PriorityQueue<>(
 			(e1, e2) -> e1.getCycleCount() - e2.getCycleCount());
 
-	/*
-	 * Default timeout values in ms
-	 */
-	private int connectTimeout = 5000;
-	private int readTimeout = 5000;
+	private final Set<TimeEndpointCountdown> timeEndpoints = new HashSet<>();
 
+	/**
+	 * Activate method.
+	 */
 	@Activate
-	protected void activate() {
+	public void activate() {
 		this.cycleSubscriber.subscribe(this::handleEvent);
 	}
 
+	/**
+	 * Deactivate method.
+	 */
 	@Deactivate
-	protected void deactivate() {
+	public void deactivate() {
 		this.cycleSubscriber.unsubscribe(this::handleEvent);
-		this.endpoints.clear();
+		this.cycleEndpoints.clear();
+		this.timeEndpoints.forEach(TimeEndpointCountdown::shutdown);
+		this.timeEndpoints.clear();
 		ThreadPoolUtils.shutdownAndAwaitTermination(this.pool, 0);
 	}
 
 	@Override
-	public void subscribe(Endpoint endpoint) {
-		if (!this.endpoints.offer(new EndpointCountdown(endpoint))) {
+	public void subscribeCycle(CycleEndpoint endpoint) {
+		if (!this.cycleEndpoints.offer(new CycleEndpointCountdown(endpoint))) {
 			this.log.warn("Unable to add " + endpoint + "!");
 		}
 	}
 
 	@Override
-	public CompletableFuture<String> request(String url) {
-		final var future = new CompletableFuture<String>();
-		this.pool.execute(this.urlFetcher.createTask(url, this.connectTimeout, this.readTimeout, future));
-		return future;
+	public void subscribeTime(TimeEndpoint endpoint) {
+		final var endpointCountdown = new TimeEndpointCountdown(endpoint);
+		this.timeEndpoints.add(endpointCountdown);
+		final var delay = endpoint.delayTimeProvider().nextRun(true, true);
+		final var future = this.pool.schedule(this.createTask(endpointCountdown), delay.amount(), delay.unit());
+		endpointCountdown.setShutdownCurrentTask(() -> future.cancel(false));
 	}
 
 	@Override
-	public void setTimeout(int connectTimeout, int readTimeout) {
-		this.connectTimeout = connectTimeout;
-		this.readTimeout = readTimeout;
+	public CompletableFuture<String> request(Endpoint endpoint) {
+		final var future = new CompletableFuture<String>();
+		this.pool.execute(() -> {
+			try {
+				final var result = this.urlFetcher.fetchEndpoint(endpoint);
+				future.complete(result);
+			} catch (Exception e) {
+				future.completeExceptionally(e);
+			}
+		});
+		return future;
 	}
 
 	private void handleEvent(Event event) {
 		switch (event.getTopic()) {
 		// TODO: Execute before TOPIC_CYCLE_BEFORE_PROCESS_IMAGE, like modbus bridge
 		case EdgeEventConstants.TOPIC_CYCLE_BEFORE_PROCESS_IMAGE -> {
 
-			if (this.endpoints.isEmpty()) {
+			if (this.cycleEndpoints.isEmpty()) {
 				return;
 			}
 
-			this.endpoints.forEach(EndpointCountdown::decreaseCycleCount);
+			this.cycleEndpoints.forEach(CycleEndpointCountdown::decreaseCycleCount);
 
-			while (this.endpoints.peek().getCycleCount() == 0) {
-				final var item = this.endpoints.poll();
+			while (this.cycleEndpoints.peek().getCycleCount() == 0) {
+				final var item = this.cycleEndpoints.poll();
 				synchronized (item) {
 					if (item.isRunning()) {
-						this.log.info("Process for " + item.endpoint + " is still running. Task is not queued twice");
-						this.endpoints.add(item.reset());
+						this.log.info(
+								"Process for " + item.cycleEndpoint + " is still running. Task is not queued twice");
+						this.cycleEndpoints.add(item.reset());
 						continue;
 					}
 
 					item.setRunning(true);
 				}
 				this.pool.execute(this.createTask(item));
 
-				this.endpoints.add(item.reset());
+				if (!this.cycleEndpoints.offer(item.reset())) {
+					this.log.warn("Unable to add " + item.cycleEndpoint + "!");
+				}
 			}
 		}
 		}
 	}
 
-	private Runnable createTask(EndpointCountdown endpointItem) {
-		final var future = new CompletableFuture<String>();
-		future.whenComplete((t, e) -> {
+	private Runnable createTask(CycleEndpointCountdown endpointItem) {
+		return () -> {
 			try {
-				if (e != null) {
-					endpointItem.endpoint.onError().accept(e);
-					return;
-				}
-				endpointItem.endpoint.result().accept(t);
+				final var result = this.urlFetcher.fetchEndpoint(endpointItem.cycleEndpoint.endpoint());
+				endpointItem.cycleEndpoint.result().accept(result);
+			} catch (Exception e) {
+				endpointItem.cycleEndpoint.onError().accept(e);
 			} finally {
 				synchronized (endpointItem) {
 					endpointItem.setRunning(false);
 				}
 			}
-		});
-		return this.urlFetcher.createTask(endpointItem.endpoint.url(), this.connectTimeout, this.readTimeout, future);
+		};
+	}
+
+	private Runnable createTask(TimeEndpointCountdown endpointCountdown) {
+		return () -> {
+			synchronized (endpointCountdown) {
+				if (endpointCountdown.isShutdown()) {
+					return;
+				}
+				endpointCountdown.setRunning(true);
+			}
+			boolean currentRunSuccessful;
+			try {
+				final var result = this.urlFetcher.fetchEndpoint(endpointCountdown.getTimeEndpoint().endpoint());
+				endpointCountdown.getTimeEndpoint().onResult().accept(result);
+				currentRunSuccessful = true;
+			} catch (Exception e) {
+				endpointCountdown.getTimeEndpoint().onError().accept(e);
+				currentRunSuccessful = false;
+			}
+			synchronized (endpointCountdown) {
+				if (endpointCountdown.isShutdown()) {
+					return;
+				}
+			}
+
+			try {
+				final var nextDelay = endpointCountdown.getTimeEndpoint().delayTimeProvider().nextRun(false,
+						currentRunSuccessful);
+				final var future = this.pool.schedule(this.createTask(endpointCountdown), nextDelay.amount(),
+						nextDelay.unit());
+				endpointCountdown.setShutdownCurrentTask(() -> future.cancel(false));
+			} catch (Exception e) {
+				if (this.pool.isShutdown()) {
+					return;
+				}
+				this.log.error("Unexpected exception during Task", e);
+			}
+		};
+	}
+
+	public PriorityQueue<CycleEndpointCountdown> getCycleEndpoints() {
+		return this.cycleEndpoints;
 	}
+
+	public Set<TimeEndpointCountdown> getTimeEndpoints() {
+		return this.timeEndpoints;
+	}
+
 }

io.openems.edge.bridge.http/src/io/openems/edge/bridge/http/CycleSubscriber.java

@@ -1,7 +1,7 @@
 package io.openems.edge.bridge.http;
 
-import java.util.LinkedList;
-import java.util.List;
+import java.util.HashSet;
+import java.util.Set;
 import java.util.function.Consumer;
 
 import org.osgi.service.component.annotations.Component;
@@ -21,13 +21,15 @@
 })
 public class CycleSubscriber implements EventHandler {
 
-	private final List<Consumer<Event>> eventHandler = new LinkedList<>();
+	private final Set<Consumer<Event>> eventHandler = new HashSet<>();
 
 	@Override
 	public void handleEvent(Event event) {
 		switch (event.getTopic()) {
 		case EdgeEventConstants.TOPIC_CYCLE_BEFORE_PROCESS_IMAGE -> {
-			this.eventHandler.forEach(t -> t.accept(event));
+			synchronized (this.eventHandler) {
+				this.eventHandler.forEach(t -> t.accept(event));
+			}
 		}
 		}
 	}
@@ -38,7 +40,9 @@ public void handleEvent(Event event) {
 	 * @param eventHandler the handler to execute on every event
 	 */
 	public void subscribe(Consumer<Event> eventHandler) {
-		this.eventHandler.add(eventHandler);
+		synchronized (this.eventHandler) {
+			this.eventHandler.add(eventHandler);
+		}
 	}
 
 	/**
@@ -49,7 +53,9 @@ public void subscribe(Consumer<Event> eventHandler) {
 	 *         found returs false
 	 */
 	public boolean unsubscribe(Consumer<Event> eventHandler) {
-		return this.eventHandler.remove(eventHandler);
+		synchronized (this.eventHandler) {
+			return this.eventHandler.remove(eventHandler);
+		}
 	}
 
 }

io.openems.edge.bridge.http/src/io/openems/edge/bridge/http/UrlFetcher.java

@@ -1,24 +1,17 @@
 package io.openems.edge.bridge.http;
 
-import java.util.concurrent.CompletableFuture;
+import io.openems.edge.bridge.http.api.BridgeHttp.Endpoint;
 
 public interface UrlFetcher {
 
 	/**
 	 * Creates a {@link Runnable} to execute a request with the given parameters.
 	 * 
-	 * @param urlString      the url to fetch
-	 * @param connectTimeout the connection timeout
-	 * @param readTimeout    the read timeout
-	 * @param future         the {@link CompletableFuture} to fulfill after the
-	 *                       fetch
+	 * @param endpoint the {@link Endpoint} to fetch
+	 * 
 	 * @return the {@link Runnable} to run to execute the fetch
+	 * @throws Exception on error
 	 */
-	public Runnable createTask(//
-			String urlString, //
-			int connectTimeout, //
-			int readTimeout, //
-			CompletableFuture<String> future //
-	);
+	public String fetchEndpoint(Endpoint endpoint) throws Exception;
 
 }