[WIP] Implementing system notifications

agent/src/main/java/li/strolch/policy/notifications/DefaultNotificationsPolicy.java

@@ -0,0 +1,51 @@
+package li.strolch.policy.notifications;
+
+import li.strolch.model.Resource;
+import li.strolch.model.StrolchModelConstants;
+import li.strolch.persistence.api.StrolchTransaction;
+import li.strolch.utils.collections.DateRange;
+
+import java.time.ZonedDateTime;
+import java.util.List;
+
+import static li.strolch.model.StrolchModelConstants.*;
+
+public class DefaultNotificationsPolicy extends NotificationsPolicy {
+	public DefaultNotificationsPolicy(StrolchTransaction tx) {
+		super(tx);
+	}
+
+	@Override
+	public List<Resource> findUserNotifications() {
+		return tx().streamResources(StrolchModelConstants.TYPE_NOTIFICATION).filter(this::isForUser).toList();
+	}
+
+	protected boolean isForUser(Resource notification) {
+		if (!isActive(notification))
+			return false;
+		if (isForAll(notification))
+			return true;
+		return isForRole(notification) || isForGroup(notification);
+	}
+
+	protected boolean isActive(Resource notification) {
+		return new DateRange()
+				.from(notification.getDate(BAG_VISIBILITY, PARAM_VISIBLE_FROM), true)
+				.to(notification.getDate(BAG_VISIBILITY, PARAM_VISIBLE_TO), true)
+				.contains(ZonedDateTime.now());
+	}
+
+	protected boolean isForAll(Resource notification) {
+		return notification.getBoolean(BAG_VISIBILITY, PARAM_FOR_ALL);
+	}
+
+	protected boolean isForRole(Resource notification) {
+		List<String> roles = notification.getStringList(BAG_VISIBILITY, PARAM_ROLES);
+		return roles.isEmpty() || roles.stream().anyMatch(r -> tx().getCertificate().hasRole(r));
+	}
+
+	protected boolean isForGroup(Resource notification) {
+		List<String> groups = notification.getStringList(BAG_VISIBILITY, PARAM_GROUPS);
+		return groups.isEmpty() || groups.stream().anyMatch(r -> tx().getCertificate().hasGroup(r));
+	}
+}

agent/src/main/java/li/strolch/policy/notifications/NotificationsPolicy.java

@@ -0,0 +1,27 @@
+package li.strolch.policy.notifications;
+
+import li.strolch.model.Resource;
+import li.strolch.model.policy.PolicyDef;
+import li.strolch.persistence.api.StrolchTransaction;
+import li.strolch.policy.StrolchPolicy;
+
+import java.util.List;
+
+import static li.strolch.model.StrolchModelConstants.PolicyConstants.POLICY_DEFAULT;
+import static li.strolch.model.policy.PolicyDef.getJavaPolicy;
+import static li.strolch.model.policy.PolicyDef.getKeyPolicy;
+
+public abstract class NotificationsPolicy extends StrolchPolicy {
+
+	public NotificationsPolicy(StrolchTransaction tx) {
+		super(tx);
+	}
+
+	public abstract List<Resource> findUserNotifications();
+
+	public static NotificationsPolicy getDefaultPolicy(StrolchTransaction tx) {
+		PolicyDef defaultDef = getKeyPolicy(NotificationsPolicy.class, POLICY_DEFAULT);
+		PolicyDef fallbackDef = getJavaPolicy(NotificationsPolicy.class, DefaultNotificationsPolicy.class);
+		return tx.getPolicy(NotificationsPolicy.class, defaultDef, fallbackDef);
+	}
+}

agent/src/main/java/li/strolch/runtime/StrolchConstants.java

@@ -96,5 +96,6 @@ public class StrolchConstants extends StrolchModelConstants {
 		public static final String PRIVILEGE_UPDATE_PREFIX = "Update";
 		public static final String PRIVILEGE_REMOVE_PREFIX = "Remove";
 		public static final String PRIVILEGE_GET_PREFIX = "Get";
+		public static final String PRIVILEGE_GET_NOTIFICATIONS = "GetNotifications";
 	}
 }

model/src/main/java/li/strolch/model/StrolchModelConstants.java

@@ -72,6 +72,7 @@ public class StrolchModelConstants {
 
 	public static final String BAG_RELATIONS = "relations";
 	public static final String BAG_PARAMETERS = "parameters";
+	public static final String BAG_VISIBILITY = "visibility";
 	public static final String TYPE_PARAMETERS = "Parameters";
 	public static final String TYPE_VERSION = "Version";
 	public static final String TYPE_MEMORY = "Memory";
@@ -82,6 +83,8 @@ public class StrolchModelConstants {
 	public static final String TYPE_CONFIGURATION = "Configuration";
 	public static final String TYPE_OBJECTIVES = "Objectives";
 	public static final String TYPE_METRIC = "Metric";
+	public static final String TYPE_NOTIFICATION = "Notification";
+	public static final String TYPE_TEXT = "Text";
 
 	public static final String RES_CONFIGURATION = "configuration";
 
@@ -99,6 +102,11 @@ public class StrolchModelConstants {
 	public static final String PARAM_START_DATE = "startDate";
 	public static final String PARAM_MODE = "mode";
 	public static final String PARAM_GROUP = "group";
+	public static final String PARAM_VISIBLE_FROM = "visibleFrom";
+	public static final String PARAM_VISIBLE_TO = "visibleTo";
+	public static final String PARAM_FOR_ALL = "forAll";
+	public static final String PARAM_ROLES = "roles";
+	public static final String PARAM_GROUPS = "groups";
 
 	public static class PolicyConstants {
 		public static final String POLICY_DEFAULT = "Default";

web-rest/src/main/java/li/strolch/rest/StrolchRestfulConstants.java

@@ -48,6 +48,8 @@ public class StrolchRestfulConstants {
 	public static final String PARAM_TO = "to";
 	public static final String PARAM_FILTER = "filter";
 	public static final String PARAM_QUERY = "query";
+	public static final String PARAM_TITLE = "title";
+	public static final String PARAM_TEXT = "text";
 
 	public static final MediaType TEXT_CSV_TYPE = new MediaType("text", "csv");
 	public static final String TEXT_CSV = "text/csv";

web-rest/src/main/java/li/strolch/rest/endpoint/NotificationResource.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2024 Robert von Burg <eitch@eitchnet.ch>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.rest.endpoint;
+
+import com.google.gson.JsonArray;
+import com.google.gson.JsonObject;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.ws.rs.GET;
+import jakarta.ws.rs.Path;
+import jakarta.ws.rs.Produces;
+import jakarta.ws.rs.core.Context;
+import jakarta.ws.rs.core.MediaType;
+import jakarta.ws.rs.core.Response;
+import li.strolch.agent.api.StrolchAgent;
+import li.strolch.model.ParameterBag;
+import li.strolch.model.Resource;
+import li.strolch.persistence.api.StrolchTransaction;
+import li.strolch.policy.notifications.NotificationsPolicy;
+import li.strolch.privilege.model.Certificate;
+import li.strolch.rest.RestfulStrolchComponent;
+import li.strolch.rest.helper.ResponseUtil;
+import li.strolch.utils.helper.StringHelper;
+import li.strolch.utils.iso8601.ISO8601;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.function.Function;
+
+import static java.util.Optional.ofNullable;
+import static li.strolch.model.StrolchModelConstants.*;
+import static li.strolch.privilege.base.PrivilegeConstants.REALM;
+import static li.strolch.rest.StrolchRestfulConstants.*;
+import static li.strolch.runtime.StrolchConstants.StrolchPrivilegeConstants.PRIVILEGE_GET_NOTIFICATIONS;
+import static li.strolch.utils.helper.ExceptionHelper.getCallerMethod;
+import static li.strolch.utils.helper.ExceptionHelper.getCallerMethodNoClass;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+@Path("strolch/notifications")
+public class NotificationResource {
+
+	private static final Logger logger = LoggerFactory.getLogger(NotificationResource.class);
+
+	private StrolchTransaction openTx(Certificate certificate) {
+		String realm = certificate.getRealm();
+		if (StringHelper.isEmpty(realm))
+			realm = REALM;
+		return RestfulStrolchComponent.getInstance().openTx(certificate, realm, getCallerMethod());
+	}
+
+	private static Certificate validateCertificate(HttpServletRequest request) {
+		Certificate cert = (Certificate) request.getAttribute(STROLCH_CERTIFICATE);
+		RestfulStrolchComponent rest = RestfulStrolchComponent.getInstance();
+		rest.validate(cert).validateAction(PRIVILEGE_GET_NOTIFICATIONS, getCallerMethodNoClass(2));
+		return cert;
+	}
+
+	@GET
+	@Produces(MediaType.APPLICATION_JSON)
+	public Response getNotifications(@Context HttpServletRequest request) {
+		Certificate cert = validateCertificate(request);
+		try (StrolchTransaction tx = openTx(cert)) {
+			List<Resource> notifications = NotificationsPolicy.getDefaultPolicy(tx).findUserNotifications();
+			Function<Resource, JsonObject> visitor = notificationToJson(tx.getAgent(), cert);
+			return ResponseUtil.toResponse(DATA, notifications.stream().map(visitor).filter(Objects::nonNull).toList());
+		} catch (Exception e) {
+			logger.error(e.getMessage(), e);
+			return ResponseUtil.toResponse(e);
+		}
+	}
+
+	private static Function<Resource, JsonObject> notificationToJson(StrolchAgent agent, Certificate cert) {
+		return notification -> {
+			JsonObject notificationJ = new JsonObject();
+
+			String lang = cert.getLocale().getLanguage();
+			Optional<ParameterBag> textBagO = ofNullable(notification.getParameterBag(lang))
+					.or(() -> ofNullable(notification.getParameterBag(agent.getLocale().getLanguage())))
+					.or(() -> notification.streamOfParameterBagsByType(TYPE_TEXT).findFirst());
+			if (textBagO.isEmpty())
+				return null;
+			ParameterBag textBag = textBagO.get();
+
+			notificationJ.addProperty(PARAM_TITLE, textBag.getString(PARAM_TITLE));
+			notificationJ.addProperty(PARAM_TEXT, textBag.getString(PARAM_TEXT));
+			notificationJ.addProperty(PARAM_VISIBLE_FROM, ISO8601.toString(textBag.getDate(PARAM_VISIBLE_FROM)));
+			notificationJ.addProperty(PARAM_VISIBLE_TO, ISO8601.toString(textBag.getDate(PARAM_VISIBLE_TO)));
+
+			return notificationJ;
+		};
+	}
+}