Add collaboration feature

Issue-ID: SDC-767
Change-Id: I14fb4c1f54086ed03a56a7ff7fab9ecd40381795
Signed-off-by: talig <talig@amdocs.com>

7 files changed, 587 insertions, 0 deletions

diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/config/ConfigurationManager.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/config/ConfigurationManager.java
new file mode 100644
index 0000000000..d960b8b9dc
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/config/ConfigurationManager.java
@@ -0,0 +1,113 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.notification.config;
+
+import org.openecomp.sdc.logging.api.Logger;
+import org.openecomp.sdc.logging.api.LoggerFactory;
+import org.openecomp.sdc.tosca.services.YamlUtil;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.function.BiConsumer;
+
+public class ConfigurationManager {
+
+    private static final String CONFIGURATION_YAML_FILE = "onboarding_configuration.yaml";
+    private static final String NOTIFICATIONS_CONFIG = "notifications";
+
+    private LinkedHashMap<String, Object> notificationsConfiguration;
+    private static final Logger LOGGER = LoggerFactory.getLogger(ConfigurationManager.class);
+    private static final ConfigurationManager SINGLETON = new ConfigurationManager();
+
+    public static ConfigurationManager getInstance() {
+        return SINGLETON;
+    }
+
+    private ConfigurationManager() {
+        initConfiguration();
+    }
+
+    private void initConfiguration() {
+
+        YamlUtil yamlUtil = new YamlUtil();
+        readConfigurationFromStream(yamlUtil, (filename, stream) -> {
+
+            if (stream == null) {
+                LOGGER.warn("Configuration not found: " + filename + ". Using defaults");
+                return;
+            }
+
+            Map<String, LinkedHashMap<String, Object>> configurationMap = yamlUtil.yamlToMap(stream);
+            if (configurationMap == null) {
+                LOGGER.warn("Configuration cannot be parsed: " + filename + ". Using defaults");
+                return;
+            }
+
+            notificationsConfiguration = configurationMap.get(NOTIFICATIONS_CONFIG);
+            if (notificationsConfiguration == null) {
+                LOGGER.error(NOTIFICATIONS_CONFIG +
+                        " is missing in configuration file '" + filename + "'. Using defaults");
+            }
+        });
+    }
+
+    private void readConfigurationFromStream(YamlUtil yamlUtil,
+                                             BiConsumer<String, InputStream> reader) {
+
+        String configurationYamlFile = System.getProperty(CONFIGURATION_YAML_FILE);
+
+        try {
+
+            if (configurationYamlFile == null) {
+
+                try (InputStream inputStream =
+                             yamlUtil.loadYamlFileIs("/" + CONFIGURATION_YAML_FILE)) {
+                    reader.accept(CONFIGURATION_YAML_FILE, inputStream);
+                }
+
+            } else {
+
+                try (InputStream inputStream = new FileInputStream(configurationYamlFile)) {
+                    reader.accept(configurationYamlFile, inputStream);
+                }
+            }
+
+        } catch (IOException e) {
+            LOGGER.error("Failed to read configuration", e);
+        }
+    }
+
+    public <T> T getConfigValue(String name, T defaultValue) {
+
+        Object value = notificationsConfiguration.get(name);
+
+        try {
+            return value == null ? defaultValue : (T) value;
+        } catch (ClassCastException e) {
+            LOGGER.warn(String.format("Failed to read configuration property '%s' as requested type. Using default '%s'",
+                    name, defaultValue), e);
+            return defaultValue;
+        }
+    }
+}
diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/types/NotificationEntityDto.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/types/NotificationEntityDto.java
new file mode 100644
index 0000000000..a415d9e081
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/types/NotificationEntityDto.java
@@ -0,0 +1,103 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.notification.types;
+
+import java.util.Map;
+import java.util.UUID;
+
+public class NotificationEntityDto {
+  private boolean read;
+  private UUID eventId;
+  private String dateTime;
+  private String eventType;
+  private Map<String, Object> eventAttributes;
+
+  public NotificationEntityDto() {
+  }
+  public NotificationEntityDto(boolean read, UUID eventId, String eventType,
+                               Map<String, Object> eventAttributes) {
+    this.read = read;
+    this.eventId = eventId;
+    this.eventType = eventType;
+    this.eventAttributes = eventAttributes;
+  }
+
+  public NotificationEntityDto(boolean read, UUID eventId,String eventType,
+                               Map<String, Object> eventAttributes, String dateTime) {
+    this.read = read;
+    this.eventId = eventId;
+    this.dateTime = dateTime;
+    this.eventType = eventType;
+    this.eventAttributes = eventAttributes;
+  }
+
+  public boolean isRead() {
+    return read;
+  }
+
+  public void setRead(boolean read) {
+    this.read = read;
+  }
+
+  public UUID getEventId() {
+    return eventId;
+  }
+
+  public void setEventId(UUID eventId) {
+    this.eventId = eventId;
+  }
+
+  public String getEventType() {
+    return eventType;
+  }
+
+  public void setEventType(String eventType) {
+    this.eventType = eventType;
+  }
+
+  public Map<String, Object> getEventAttributes() {
+    return eventAttributes;
+  }
+
+  public void setEventAttributes(Map<String, Object> eventAttributes) {
+    this.eventAttributes = eventAttributes;
+  }
+
+  public String getDateTime() {
+    return dateTime;
+  }
+
+  public void setDateTime(String dateTime) {
+    this.dateTime = dateTime;
+  }
+
+  @Override
+  public String toString() {
+    return "NotificationEntityDto {"
+        + ", state='" + (read ? "Read" : "Noread") + '\''
+        + ", dateTime='" + dateTime + '\''
+        + ", eventId='" + eventId + '\''
+        + ", eventType='" + eventType + '\''
+        + ", eventAttributes='" + eventAttributes + '\''
+        + '}';
+  }
+
+}
diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/types/NotificationsStatusDto.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/types/NotificationsStatusDto.java
new file mode 100644
index 0000000000..fd8d32090e
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/types/NotificationsStatusDto.java
@@ -0,0 +1,72 @@
+package org.openecomp.sdc.notification.types;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+
+/**
+ * @author avrahamg
+ * @since June 29, 2017
+ */
+public class NotificationsStatusDto {
+    private List<NotificationEntityDto> notifications;
+    private List<UUID> newEntries = new ArrayList<>();
+    private UUID lastScanned;
+    private UUID endOfPage;
+    private long numOfNotSeenNotifications;
+
+    public NotificationsStatusDto() {
+    }
+
+    public List<NotificationEntityDto> getNotifications() {
+        return notifications;
+    }
+
+    public void setNotifications(
+        List<NotificationEntityDto> notifications) {
+        this.notifications = notifications;
+    }
+
+    public List<UUID> getNewEntries() {
+        return newEntries;
+    }
+
+    public void setNewEntries(List<UUID> newEntries) {
+        this.newEntries = newEntries;
+    }
+
+    public UUID getLastScanned() {
+        return lastScanned;
+    }
+
+    public void setLastScanned(UUID lastScanned) {
+        this.lastScanned = lastScanned;
+    }
+
+    public UUID getEndOfPage() {
+        return endOfPage;
+    }
+
+    public void setEndOfPage(UUID endOfPage) {
+        this.endOfPage = endOfPage;
+    }
+
+    public long getNumOfNotSeenNotifications() {
+        return numOfNotSeenNotifications;
+    }
+
+    public void setNumOfNotSeenNotifications(long numOfNotSeenNotifications) {
+        this.numOfNotSeenNotifications = numOfNotSeenNotifications;
+    }
+
+    @Override
+    public String toString() {
+        return "NotificationsStatusDto{" +
+                "notifications=" + notifications +
+                ", newEntries=" + newEntries +
+                ", lastScanned=" + lastScanned +
+                ", endOfPage=" + endOfPage +
+                ", numOfNotSeenNotifications=" + numOfNotSeenNotifications +
+                '}';
+    }
+}
diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NewNotificationsReader.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NewNotificationsReader.java
new file mode 100644
index 0000000000..75b9f5c786
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NewNotificationsReader.java
@@ -0,0 +1,29 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.notification.workers;
+
+import org.openecomp.sdc.notification.types.NotificationsStatusDto;
+
+import java.util.UUID;
+
+public interface NewNotificationsReader {
+	NotificationsStatusDto getNewNotifications(String ownerId, UUID eventId, int limit);
+}
diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NotificationReceiver.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NotificationReceiver.java
new file mode 100644
index 0000000000..ee802640c4
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NotificationReceiver.java
@@ -0,0 +1,69 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.notification.workers;
+
+import org.openecomp.sdc.notification.types.NotificationsStatusDto;
+
+import java.util.UUID;
+import java.util.function.Consumer;
+
+
+
+public class NotificationReceiver {
+
+	public String ownerId = null;
+	public Consumer<NotificationsStatusDto> notesProcessor = null;
+	public UUID lastEventId = null;
+
+	NotificationReceiver(String ownerId, UUID lastEventId, Consumer<NotificationsStatusDto> notesProcessor) {
+		this.ownerId = ownerId;
+		this.lastEventId = lastEventId;
+		this.notesProcessor = notesProcessor;
+	}
+
+	NotificationReceiver(String ownerId, Consumer<NotificationsStatusDto> notesProcessor) {
+		this(ownerId, null, notesProcessor);
+	}
+
+	public void setOwnerId(String ownerId) {
+		this.ownerId = ownerId;
+	}
+
+	public String getOwnerId() {
+		return this.ownerId;
+	}
+
+	public void setNotesProcessor(Consumer<NotificationsStatusDto> notesProcessor) {
+		this.notesProcessor = notesProcessor;
+	}
+
+	public Consumer<NotificationsStatusDto> getNotesProcessor() {
+		return this.notesProcessor;
+	}
+
+	public void setLastEventId(UUID lastEventId) {
+		this.lastEventId = lastEventId;
+	}
+
+	public UUID getlastEventId() {
+		return this.lastEventId;
+	}
+}
diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NotificationWorker.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NotificationWorker.java
new file mode 100644
index 0000000000..e8c2006d5c
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/NotificationWorker.java
@@ -0,0 +1,117 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.notification.workers;
+
+import org.apache.commons.collections4.CollectionUtils;
+import org.openecomp.sdc.logging.api.Logger;
+import org.openecomp.sdc.logging.api.LoggerFactory;
+import org.openecomp.sdc.notification.config.ConfigurationManager;
+import org.openecomp.sdc.notification.types.NotificationsStatusDto;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Consumer;
+
+public class NotificationWorker {
+
+	private static final int DEFAULT_POLLING_INTERVAL = 2000;
+	private static final String POLLING_INTERVAL = "pollingIntervalMsec";
+	private static final int DEFAULT_SELECTION_LIMIT = 10;
+	private static final String SELECTION_SIZE = "selectionSize";
+
+	private static boolean stopRunning = false;
+
+	private int selectionLimit = DEFAULT_SELECTION_LIMIT;
+	private int pollingSleepInterval = DEFAULT_POLLING_INTERVAL;
+
+	private static final Logger LOGGER = LoggerFactory.getLogger(NotificationWorker.class);
+
+	private static Map<String, NotificationReceiver> activeUsers = new ConcurrentHashMap<>();
+	private NewNotificationsReader news = null;
+
+	public NotificationWorker(NewNotificationsReader news) {
+		ConfigurationManager cm = ConfigurationManager.getInstance();
+		pollingSleepInterval = cm.getConfigValue(POLLING_INTERVAL, DEFAULT_POLLING_INTERVAL);
+		selectionLimit = cm.getConfigValue(SELECTION_SIZE, DEFAULT_SELECTION_LIMIT);
+
+		Objects.requireNonNull(news, "NotificationNews object is not initialized.");
+		this.news = news;
+
+		NotificationWorker.Poller p = new Poller();
+		Thread thread = new Thread(p);
+		thread.start();
+	}
+
+	public Map<String, NotificationReceiver> getActiveUsers() {
+		return activeUsers;
+	}
+
+	public class Poller extends Thread {
+		public void run() {
+			try {
+				while (!stopRunning) {
+					pollNotifications();
+					Thread.sleep(pollingSleepInterval);
+				}
+			}
+			catch (InterruptedException e) {
+				LOGGER.error("Interrupted Exception during Notification poller launch.", e);
+			}
+		}
+
+		private void pollNotifications() {
+
+			Map<String, NotificationReceiver> currUsers = new HashMap<>();
+			currUsers.putAll(getActiveUsers());
+
+			for (NotificationReceiver receiver : currUsers.values()) {
+				String ownerId = receiver.getOwnerId();
+				UUID eventId = receiver.getlastEventId();
+				NotificationsStatusDto status = news.getNewNotifications(ownerId, eventId, selectionLimit);
+				if(Objects.nonNull(status) && CollectionUtils.isNotEmpty(status.getNotifications())) {
+					receiver.setLastEventId(status.getLastScanned());
+					receiver.getNotesProcessor().accept(status);
+				}
+			}
+		}
+
+	}
+
+	public void register(String ownerId, UUID lastDelivered, Consumer<NotificationsStatusDto> notesProcessor) {
+		NotificationReceiver receiver = new NotificationReceiver(ownerId, lastDelivered, notesProcessor);
+		activeUsers.put(ownerId, receiver);
+		LOGGER.debug("User {} is registered with eventId: {}", ownerId, receiver.getlastEventId());
+	}
+
+	public void unregister(String ownerId) {
+		activeUsers.remove(ownerId);
+		LOGGER.debug("User {} is unregistered.", ownerId);
+	}
+
+	public void stopPolling() {
+		LOGGER.debug("Stop notification polling.");
+		stopRunning = true;
+	}
+
+}
diff --git a/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/impl/NewNotificationsReaderRestImpl.java b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/impl/NewNotificationsReaderRestImpl.java
new file mode 100644
index 0000000000..a332efaf5a
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-notification-lib/openecomp-sdc-notification-worker/src/main/java/org/openecomp/sdc/notification/workers/impl/NewNotificationsReaderRestImpl.java
@@ -0,0 +1,84 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.sdc.notification.workers.impl;
+
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.openecomp.sdc.logging.api.Logger;
+import org.openecomp.sdc.logging.api.LoggerFactory;
+import org.openecomp.sdc.notification.config.ConfigurationManager;
+import org.openecomp.sdc.notification.types.NotificationsStatusDto;
+import org.openecomp.sdc.notification.workers.NewNotificationsReader;
+
+import javax.ws.rs.core.HttpHeaders;
+import javax.ws.rs.core.MediaType;
+import java.io.InputStreamReader;
+import java.util.UUID;
+
+public class NewNotificationsReaderRestImpl implements NewNotificationsReader {
+
+    private static final String USER_ID_HEADER_PARAM = "USER_ID";
+    private static final String LAST_DELIVERED_QUERY_PARAM = "LAST_DELIVERED_EVENT_ID";
+    private static final String LIMIT_QUERY_PARAM = "NOTIFICATION_ROWS_LIMIT";
+    private static final String BE_HOST = "beHost";
+    private static final String BE_PORT = "beHttpPort";
+    private static final String DEFAULT_BE_HOST = "localhost";
+    private static final int DEFAULT_BE_PORT = 8080;
+    private static final String URL = "http://%s:%d/onboarding-api/v1.0/notifications/worker?";
+    private static final ObjectMapper mapper = new ObjectMapper();
+
+    private static String beHost;
+    private static int bePort;
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(NewNotificationsReaderRestImpl.class);
+
+    public NewNotificationsReaderRestImpl() {
+        ConfigurationManager cm = ConfigurationManager.getInstance();
+        bePort = cm.getConfigValue(BE_PORT, DEFAULT_BE_PORT);
+        beHost = cm.getConfigValue(BE_HOST, DEFAULT_BE_HOST);
+    }
+
+    public NotificationsStatusDto getNewNotifications(String ownerId, UUID eventId, int limit) {
+        HttpClient client = HttpClientBuilder.create().build();
+        String url = String.format(URL, beHost, bePort);
+
+        url = url + LIMIT_QUERY_PARAM + "=" + limit;
+        if (eventId != null) {
+            url = url + "&" + LAST_DELIVERED_QUERY_PARAM + "=" + eventId;
+        }
+
+        HttpGet request = new HttpGet(url);
+        request.addHeader(HttpHeaders.ACCEPT, MediaType.APPLICATION_JSON);
+        request.addHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON);
+        request.addHeader(USER_ID_HEADER_PARAM, ownerId);
+
+        try {
+            HttpResponse response = client.execute(request);
+            return mapper.readValue(new InputStreamReader(response.getEntity().getContent()), NotificationsStatusDto.class);
+        } catch (Exception e) {
+            LOGGER.error("Failed to execute the request {}", url, e);
+            return null;
+        }
+    }
+}