Fetching data node by xpath - rest and service layers

IssueID: CPS-71
Change-Id: I54801fc12a8aa700d85e774780c9990b7f19c747
Signed-off-by: Ruslan Kashapov <ruslan.kashapov@pantheon.tech>

1 files changed, 18 insertions, 0 deletions

diff --git a/cps-service/src/main/java/org/onap/cps/api/CpsDataService.java b/cps-service/src/main/java/org/onap/cps/api/CpsDataService.java
index a8f49655a..7960d12ef 100644
--- a/cps-service/src/main/java/org/onap/cps/api/CpsDataService.java
+++ b/cps-service/src/main/java/org/onap/cps/api/CpsDataService.java
@@ -1,6 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2020 Nordix Foundation
+ *  Modifications Copyright (C) 2021 Pantheon.tech
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
@@ -20,12 +21,15 @@
 package org.onap.cps.api;
 
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.onap.cps.spi.FetchDescendantsOption;
 import org.onap.cps.spi.exceptions.DataValidationException;
+import org.onap.cps.spi.model.DataNode;
 
 /*
  * Datastore interface for handling CPS data.
  */
 public interface CpsDataService {
+
     /**
      * Persists data for the given anchor and dataspace.
      *
@@ -35,4 +39,18 @@ public interface CpsDataService {
      * @throws DataValidationException when json data is invalid
      */
     void saveData(@NonNull String dataspaceName, @NonNull String anchorName, @NonNull String jsonData);
+
+    /**
+     * Retrieves datanode by XPath for given dataspace and anchor.
+     *
+     * @param dataspaceName          dataspace name
+     * @param anchorName             anchor name
+     * @param xpath                  xpath
+     * @param fetchDescendantsOption defines the scope of data to fetch: either single node or all the descendant nodes
+     *                               (recursively) as well
+     * @return data node object
+     */
+    DataNode getDataNode(@NonNull String dataspaceName, @NonNull String anchorName, @NonNull String xpath,
+        @NonNull FetchDescendantsOption fetchDescendantsOption);
+
 }