[chromecast] Added configuration flag to disable background discovery (#11689)

* Added configuration flag to disable background discovery

Signed-off-by: Christoph Weitkamp <github@christophweitkamp.de>

bundles/org.openhab.binding.chromecast/README.md

@@ -28,15 +28,21 @@ Configure a Callback URL when the Chromecast cannot connect using the Primary Ad
 
 ## Discovery
 
-Chromecast devices are discovered on the network using UPnP.
+Chromecast devices are discovered on the network using mDNS.
 No authentication is required for accessing the devices on the network.
+Auto-discovery is enabled by default.
+To disable it, you can add the following line to `<openHAB-conf>/services/runtime.cfg`:
+
+```
+discovery.chromecast:background=false
+```
 
 ## Thing Configuration
 
 Chromecast devices can also be manually added.
 The only configuration parameter is the `ipAddress`.
 For an audio group also the port is necessary.
-The autodiscovery process finds the port automatically.
+The auto-discovery process finds the port automatically.
 With manual thing configuration the parameter `port` must be determined manually.
 
 Example for audio group:

bundles/org.openhab.binding.chromecast/src/main/java/org/openhab/binding/chromecast/internal/discovery/ChromecastDiscoveryParticipant.java

@@ -14,7 +14,7 @@ package org.openhab.binding.chromecast.internal.discovery;
 
 import static org.openhab.binding.chromecast.internal.ChromecastBindingConstants.*;
 
-import java.util.HashMap;
+import java.util.Dictionary;
 import java.util.Map;
 import java.util.Set;
 
@@ -24,22 +24,28 @@ import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.eclipse.jdt.annotation.Nullable;
 import org.openhab.core.config.discovery.DiscoveryResult;
 import org.openhab.core.config.discovery.DiscoveryResultBuilder;
+import org.openhab.core.config.discovery.DiscoveryService;
 import org.openhab.core.config.discovery.mdns.MDNSDiscoveryParticipant;
 import org.openhab.core.thing.ThingTypeUID;
 import org.openhab.core.thing.ThingUID;
+import org.osgi.service.component.ComponentContext;
+import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
+import org.osgi.service.component.annotations.Modified;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
- * The {@link ChromecastDiscoveryParticipant} is responsible for discovering Chromecast devices through UPnP.
+ * The {@link ChromecastDiscoveryParticipant} is responsible for discovering Chromecast devices through mDNS.
  *
  * @author Kai Kreuzer - Initial contribution
  * @author Daniel Walters - Change discovery protocol to mDNS
+ * @author Christoph Weitkamp - Use "discovery.chromecast:background=false" to disable discovery service
  */
-@Component
+@Component(configurationPid = "discovery.chromecast")
 @NonNullByDefault
 public class ChromecastDiscoveryParticipant implements MDNSDiscoveryParticipant {
+
     private final Logger logger = LoggerFactory.getLogger(ChromecastDiscoveryParticipant.class);
 
     private static final String PROPERTY_MODEL = "md";
@@ -47,6 +53,27 @@ public class ChromecastDiscoveryParticipant implements MDNSDiscoveryParticipant
     private static final String PROPERTY_DEVICE_ID = "id";
     private static final String SERVICE_TYPE = "_googlecast._tcp.local.";
 
+    private boolean isAutoDiscoveryEnabled = true;
+
+    @Activate
+    protected void activate(ComponentContext componentContext) {
+        activateOrModifyService(componentContext);
+    }
+
+    @Modified
+    protected void modified(ComponentContext componentContext) {
+        activateOrModifyService(componentContext);
+    }
+
+    private void activateOrModifyService(ComponentContext componentContext) {
+        Dictionary<String, @Nullable Object> properties = componentContext.getProperties();
+        String autoDiscoveryPropertyValue = (String) properties
+                .get(DiscoveryService.CONFIG_PROPERTY_BACKGROUND_DISCOVERY);
+        if (autoDiscoveryPropertyValue != null && !autoDiscoveryPropertyValue.isBlank()) {
+            isAutoDiscoveryEnabled = Boolean.valueOf(autoDiscoveryPropertyValue);
+        }
+    }
+
     @Override
     public Set<ThingTypeUID> getSupportedThingTypeUIDs() {
         return SUPPORTED_THING_TYPES_UIDS;
@@ -59,25 +86,20 @@ public class ChromecastDiscoveryParticipant implements MDNSDiscoveryParticipant
 
     @Override
     public @Nullable DiscoveryResult createResult(ServiceInfo service) {
-        final ThingUID uid = getThingUID(service);
+        if (isAutoDiscoveryEnabled) {
-        if (uid == null) {
+            ThingUID uid = getThingUID(service);
-            return null;
+            if (uid != null) {
-        }
-
-        final Map<String, Object> properties = new HashMap<>(5);
                 String host = service.getHostAddresses()[0];
-        properties.put(HOST, host);
                 int port = service.getPort();
-        properties.put(PORT, port);
                 logger.debug("Chromecast Found: {} {}", host, port);
                 String id = service.getPropertyString(PROPERTY_DEVICE_ID);
-        properties.put(DEVICE_ID, id);
                 String friendlyName = service.getPropertyString(PROPERTY_FRIENDLY_NAME); // friendly name;
-
+                return DiscoveryResultBuilder.create(uid).withThingType(getThingType(service))
-        final DiscoveryResult result = DiscoveryResultBuilder.create(uid).withThingType(getThingType(service))
+                        .withProperties(Map.of(HOST, host, PORT, port, DEVICE_ID, id))
-                .withProperties(properties).withRepresentationProperty(DEVICE_ID).withLabel(friendlyName).build();
+                        .withRepresentationProperty(DEVICE_ID).withLabel(friendlyName).build();
-
+            }
-        return result;
+        }
+        return null;
     }
 
     private @Nullable ThingTypeUID getThingType(final ServiceInfo service) {
@@ -102,8 +124,7 @@ public class ChromecastDiscoveryParticipant implements MDNSDiscoveryParticipant
         if (thingTypeUID != null) {
             String id = service.getPropertyString(PROPERTY_DEVICE_ID); // device id
             return new ThingUID(thingTypeUID, id);
-        } else {
+        }
         return null;
     }
-    }
 }