[mqtt.homeassistant] fix unbounded growth of config for device_trigger (

openhab#17894)

Because of how it shares a channel, whenever openHAB was rebooted and it
would first restore the device trigger components from the channel configuration,
and then from the MQTT message, it didn't identify it as the same component
as before, and so would merge into another instance of itself. My Things.json
is normally 13MB, and had grown to 545MB, and my openHAB was constantly having
memory issues! So now just make sure we only keep unique information, which
will automatically clean up anyone in a bad state.

Signed-off-by: Cody Cutrer <[email protected]>

bundles/org.openhab.binding.mqtt.homeassistant/src/main/java/org/openhab/binding/mqtt/homeassistant/internal/component/DeviceTrigger.java

@@ -111,17 +111,22 @@ public boolean merge(DeviceTrigger other) {
         newConfiguration.put("nodeid", currentConfiguration.get("nodeid"));
         Object objectIdObject = currentConfiguration.get("objectid");
         if (objectIdObject instanceof String objectIdString) {
-            newConfiguration.put("objectid", List.of(objectIdString, other.getHaID().objectID));
+            if (!objectIdString.equals(other.getHaID().objectID)) {
+                newConfiguration.put("objectid", List.of(objectIdString, other.getHaID().objectID));
+            }
         } else if (objectIdObject instanceof List<?> objectIdList) {
-            newConfiguration.put("objectid",
-                    Stream.concat(objectIdList.stream(), Stream.of(other.getHaID().objectID)).toList());
+            newConfiguration.put("objectid", Stream.concat(objectIdList.stream(), Stream.of(other.getHaID().objectID))
+                    .sorted().distinct().toList());
         }
         Object configObject = currentConfiguration.get("config");
         if (configObject instanceof String configString) {
-            newConfiguration.put("config", List.of(configString, other.getChannelConfigurationJson()));
+            if (!configString.equals(other.getChannelConfigurationJson())) {
+                newConfiguration.put("config", List.of(configString, other.getChannelConfigurationJson()));
+            }
         } else if (configObject instanceof List<?> configList) {
             newConfiguration.put("config",
-                    Stream.concat(configList.stream(), Stream.of(other.getChannelConfigurationJson())).toList());
+                    Stream.concat(configList.stream(), Stream.of(other.getChannelConfigurationJson())).sorted()
+                            .distinct().toList());
         }
 
         // Append payload to allowed values
@@ -130,7 +135,8 @@ public boolean merge(DeviceTrigger other) {
             // Need to accept anything
             value = new TextValue();
         } else {
-            String[] newValues = Stream.concat(payloads.stream(), Stream.of(otherPayload)).toArray(String[]::new);
+            String[] newValues = Stream.concat(payloads.stream(), Stream.of(otherPayload)).distinct()
+                    .toArray(String[]::new);
             value = new TextValue(newValues);
         }