Notification plugin interface and models

Currently Alerting, ISM and Reporting plugins are expected to make call to
Notification plugin to send notification.

The plugins can communicate using REST or Transport layer.
Transport layer makes call to same node and hence avoids network hop
so transport layer communication is preferred.
common-utils contains the model (with marshaling/unmarshaling code) for the communication.
above mentioned plugins consumes common-utils and uses these models for communication.

Note: Plugins runs on different JVM and hence the notification plugins needs to
check if the class is same before accessing the values.
transport marshaling/unmarshaling ( writeTo(output: StreamOutput) and
constructor(input: StreamInput) of models) are used for this purpose.
REST APIs in notification plugin uses toXContent and parse marshaling/unmarshaling

[Tests]
Contains unit test for all model classes

Signed-off-by: @akbhatta

detekt.yml

@@ -20,4 +20,12 @@ style:
     max: 10
   ReturnCount:
     active: true
-    max: 10
+    max: 10
+
+complexity:
+  LargeClass:
+    excludes: ['**/test/**']
+  LongMethod:
+    excludes: ['**/test/**']
+  LongParameterList:
+    excludes: ['**/test/**']

src/main/kotlin/org/opensearch/commons/notifications/NotificationConstants.kt

@@ -0,0 +1,71 @@
+package org.opensearch.commons.notifications
+
+/**
+ * Class containing Internal constants like JSON tags and defaults.
+ */
+object NotificationConstants {
+    const val CONFIG_ID_TAG = "config_id"
+    const val CONFIG_ID_LIST_TAG = "config_id_list"
+    const val EVENT_ID_TAG = "event_id"
+    const val EVENT_ID_LIST_TAG = "event_id_list"
+    const val EMAIL_ACCOUNT_ID_TAG = "email_account_id"
+    const val REFERENCE_ID_TAG = "reference_id"
+    const val CHANNEL_ID_LIST_TAG = "channel_id_list"
+    const val CONFIG_NAME_TAG = "config_name"
+    const val CONFIG_TYPE_TAG = "config_type"
+    const val CONFIG_TAG = "config"
+    const val EVENT_TAG = "event"
+    const val EVENT_SOURCE_TAG = "event_source"
+    const val FEATURE_TAG = "feature"
+    const val THREAD_CONTEXT_TAG = "context"
+    const val CHANNEL_MESSAGE_TAG = "channel_message"
+    const val TEXT_DESCRIPTION_TAG = "text_description"
+    const val HTML_DESCRIPTION_TAG = "html_description"
+    const val ATTACHMENT_TAG = "attachment"
+    const val FILE_NAME_TAG = "file_name"
+    const val FILE_ENCODING_TAG = "file_encoding"
+    const val FILE_DATA_TAG = "file_data"
+    const val FILE_CONTENT_TYPE_TAG = "file_content_type"
+    const val RECIPIENT_TAG = "recipient"
+    const val RECIPIENT_LIST_TAG = "recipient_list"
+    const val EMAIL_RECIPIENT_STATUS_TAG = "email_recipient_status"
+    const val EMAIL_GROUP_ID_LIST_TAG = "email_group_id_list"
+    const val STATUS_CODE_TAG = "status_code"
+    const val STATUS_TEXT_TAG = "status_text"
+    const val DELIVERY_STATUS_TAG = "delivery_status"
+    const val NAME_TAG = "name"
+    const val DESCRIPTION_TAG = "description"
+    const val IS_ENABLED_TAG = "is_enabled"
+    const val FEATURE_LIST_TAG = "feature_list"
+    const val TITLE_TAG = "title"
+    const val SEVERITY_TAG = "severity"
+    const val TAGS_TAG = "tags"
+    const val URL_TAG = "url"
+    const val HEADER_PARAMS_TAG = "header_params"
+    const val HOST_TAG = "host"
+    const val PORT_TAG = "port"
+    const val METHOD_TAG = "method"
+    const val FROM_ADDRESS_TAG = "from_address"
+    const val UPDATED_TIME_TAG = "last_updated_time_ms"
+    const val CREATED_TIME_TAG = "created_time_ms"
+    const val TENANT_TAG = "tenant"
+    const val CONFIG_LIST_TAG = "config_list"
+    const val EVENT_LIST_TAG = "event_list"
+    const val FEATURE_CONFIG_LIST_TAG = "feature_channel_list"
+    const val DELETE_RESPONSE_LIST_TAG = "delete_response_list"
+    const val FROM_INDEX_TAG = "from_index"
+    const val MAX_ITEMS_TAG = "max_items"
+    const val SORT_FIELD_TAG = "sort_field"
+    const val SORT_ORDER_TAG = "sort_order"
+    const val FILTER_PARAM_LIST_TAG = "filter_param_list"
+    const val STATUS_LIST_TAG = "status_list"
+    const val START_INDEX_TAG = "start_index"
+    const val TOTAL_HITS_TAG = "total_hits"
+    const val TOTAL_HIT_RELATION_TAG = "total_hit_relation"
+    const val QUERY_TAG = "query"
+    const val COMPACT_TAG = "compact"
+    const val CONFIG_TYPE_LIST_TAG = "config_type_list"
+    const val PLUGIN_FEATURES_TAG = "plugin_features"
+
+    const val DEFAULT_MAX_ITEMS = 1000
+}

src/main/kotlin/org/opensearch/commons/notifications/NotificationsPluginInterface.kt

@@ -0,0 +1,215 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ *
+ * Modifications Copyright OpenSearch Contributors. See
+ * GitHub history for details.
+ */
+
+/*
+ * Copyright 2021 Amazon.com, Inc. or its affiliates. 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.
+ * A copy of the License is located at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * or in the "license" file accompanying this file. This file 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 org.opensearch.commons.notifications
+
+import org.opensearch.action.ActionListener
+import org.opensearch.client.node.NodeClient
+import org.opensearch.commons.ConfigConstants.OPENSEARCH_SECURITY_USER_INFO_THREAD_CONTEXT
+import org.opensearch.commons.notifications.action.CreateNotificationConfigRequest
+import org.opensearch.commons.notifications.action.CreateNotificationConfigResponse
+import org.opensearch.commons.notifications.action.DeleteNotificationConfigRequest
+import org.opensearch.commons.notifications.action.DeleteNotificationConfigResponse
+import org.opensearch.commons.notifications.action.GetFeatureChannelListRequest
+import org.opensearch.commons.notifications.action.GetFeatureChannelListResponse
+import org.opensearch.commons.notifications.action.GetNotificationConfigRequest
+import org.opensearch.commons.notifications.action.GetNotificationConfigResponse
+import org.opensearch.commons.notifications.action.GetNotificationEventRequest
+import org.opensearch.commons.notifications.action.GetNotificationEventResponse
+import org.opensearch.commons.notifications.action.GetPluginFeaturesRequest
+import org.opensearch.commons.notifications.action.GetPluginFeaturesResponse
+import org.opensearch.commons.notifications.action.NotificationsActions.CREATE_NOTIFICATION_CONFIG_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.DELETE_NOTIFICATION_CONFIG_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.GET_FEATURE_CHANNEL_LIST_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.GET_NOTIFICATION_CONFIG_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.GET_NOTIFICATION_EVENT_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.GET_PLUGIN_FEATURES_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.SEND_NOTIFICATION_ACTION_TYPE
+import org.opensearch.commons.notifications.action.NotificationsActions.UPDATE_NOTIFICATION_CONFIG_ACTION_TYPE
+import org.opensearch.commons.notifications.action.SendNotificationRequest
+import org.opensearch.commons.notifications.action.SendNotificationResponse
+import org.opensearch.commons.notifications.action.UpdateNotificationConfigRequest
+import org.opensearch.commons.notifications.action.UpdateNotificationConfigResponse
+import org.opensearch.commons.notifications.model.ChannelMessage
+import org.opensearch.commons.notifications.model.EventSource
+import org.opensearch.commons.utils.SecureClientWrapper
+
+/**
+ * All the transport action plugin interfaces for the Notification plugin
+ */
+object NotificationsPluginInterface {
+
+    /**
+     * Create notification configuration.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun createNotificationConfig(
+        client: NodeClient,
+        request: CreateNotificationConfigRequest,
+        listener: ActionListener<CreateNotificationConfigResponse>
+    ) {
+        client.execute(
+            CREATE_NOTIFICATION_CONFIG_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Update notification configuration.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun updateNotificationConfig(
+        client: NodeClient,
+        request: UpdateNotificationConfigRequest,
+        listener: ActionListener<UpdateNotificationConfigResponse>
+    ) {
+        client.execute(
+            UPDATE_NOTIFICATION_CONFIG_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Delete notification configuration.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun deleteNotificationConfig(
+        client: NodeClient,
+        request: DeleteNotificationConfigRequest,
+        listener: ActionListener<DeleteNotificationConfigResponse>
+    ) {
+        client.execute(
+            DELETE_NOTIFICATION_CONFIG_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Get notification configuration.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun getNotificationConfig(
+        client: NodeClient,
+        request: GetNotificationConfigRequest,
+        listener: ActionListener<GetNotificationConfigResponse>
+    ) {
+        client.execute(
+            GET_NOTIFICATION_CONFIG_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Get notification events.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun getNotificationEvent(
+        client: NodeClient,
+        request: GetNotificationEventRequest,
+        listener: ActionListener<GetNotificationEventResponse>
+    ) {
+        client.execute(
+            GET_NOTIFICATION_EVENT_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Get notification plugin features.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun getPluginFeatures(
+        client: NodeClient,
+        request: GetPluginFeaturesRequest,
+        listener: ActionListener<GetPluginFeaturesResponse>
+    ) {
+        client.execute(
+            GET_PLUGIN_FEATURES_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Get notification channel configuration enabled for a feature.
+     * @param client Node client for making transport action
+     * @param request The request object
+     * @param listener The listener for getting response
+     */
+    fun getFeatureChannelList(
+        client: NodeClient,
+        request: GetFeatureChannelListRequest,
+        listener: ActionListener<GetFeatureChannelListResponse>
+    ) {
+        client.execute(
+            GET_FEATURE_CHANNEL_LIST_ACTION_TYPE,
+            request,
+            listener
+        )
+    }
+
+    /**
+     * Send notification API enabled for a feature. No REST API. Internal API only for Inter plugin communication.
+     * @param client Node client for making transport action
+     * @param eventSource The notification event information
+     * @param channelMessage The notification message
+     * @param channelIds The list of channel ids to send message to.
+     * @param listener The listener for getting response
+     */
+    fun sendNotification(
+        client: NodeClient,
+        eventSource: EventSource,
+        channelMessage: ChannelMessage,
+        channelIds: List<String>,
+        listener: ActionListener<SendNotificationResponse>
+    ) {
+        val threadContext: String? =
+            client.threadPool().threadContext.getTransient<String>(OPENSEARCH_SECURITY_USER_INFO_THREAD_CONTEXT)
+        val wrapper = SecureClientWrapper(client) // Executing request in privileged mode
+        wrapper.execute(
+            SEND_NOTIFICATION_ACTION_TYPE,
+            SendNotificationRequest(eventSource, channelMessage, channelIds, threadContext),
+            listener
+        )
+    }
+}

src/main/kotlin/org/opensearch/commons/notifications/action/BaseResponse.kt

@@ -0,0 +1,59 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ *
+ * Modifications Copyright OpenSearch Contributors. See
+ * GitHub history for details.
+ */
+
+/*
+ * Copyright 2021 Amazon.com, Inc. or its affiliates. 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.
+ * A copy of the License is located at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * or in the "license" file accompanying this file. This file 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 org.opensearch.commons.notifications.action
+
+import org.opensearch.action.ActionResponse
+import org.opensearch.common.io.stream.StreamInput
+import org.opensearch.common.xcontent.ToXContentObject
+import org.opensearch.rest.RestStatus
+import java.io.IOException
+
+/**
+ * Base response which give REST status.
+ */
+abstract class BaseResponse : ActionResponse, ToXContentObject {
+
+    /**
+     * constructor for creating the class
+     */
+    constructor()
+
+    /**
+     * {@inheritDoc}
+     */
+    @Throws(IOException::class)
+    constructor(input: StreamInput) : super(input)
+
+    /**
+     * get rest status for the response. Useful override for multi-status response.
+     * @return RestStatus for the response
+     */
+    open fun getStatus(): RestStatus {
+        return RestStatus.OK
+    }
+}