Allow limiting results in queryDataLeaf

This exposes queryResultLimit parameter in queryDataLeaf,
same as was implemented for queryDataNodes API.

Issue-ID: CPS-2680
Signed-off-by: danielhanrahan <daniel.hanrahan@est.tech>
Change-Id: Ieb922ac1acc91dbfd67fb5ade7856213a2f93ce8

4 files changed, 28 insertions, 6 deletions

diff --git a/cps-service/src/main/java/org/onap/cps/api/CpsQueryService.java b/cps-service/src/main/java/org/onap/cps/api/CpsQueryService.java
index 30c8bbbdf3..d6c1f7fc60 100644
--- a/cps-service/src/main/java/org/onap/cps/api/CpsQueryService.java
+++ b/cps-service/src/main/java/org/onap/cps/api/CpsQueryService.java
@@ -74,6 +74,19 @@ public interface CpsQueryService {
     <T> Set<T> queryDataLeaf(String dataspaceName, String anchorName, String cpsPath, Class<T> targetClass);
 
     /**
+     * Get data leaf for the given dataspace and anchor by cps path.
+     *
+     * @param dataspaceName      dataspace name
+     * @param anchorName         anchor name
+     * @param cpsPath            cps path
+     * @param queryResultLimit   the maximum number of data nodes to return; if less than 1, returns all matching nodes
+     * @param targetClass        class of the expected data type
+     * @return a collection of data objects of expected type
+     */
+    <T> Set<T> queryDataLeaf(String dataspaceName, String anchorName, String cpsPath, int queryResultLimit,
+                             Class<T> targetClass);
+
+    /**
      * Get data nodes for the given dataspace across all anchors by cps path.
      *
      * @param dataspaceName dataspace name
diff --git a/cps-service/src/main/java/org/onap/cps/impl/CpsQueryServiceImpl.java b/cps-service/src/main/java/org/onap/cps/impl/CpsQueryServiceImpl.java
index a3884820c7..5abdd0fe2b 100644
--- a/cps-service/src/main/java/org/onap/cps/impl/CpsQueryServiceImpl.java
+++ b/cps-service/src/main/java/org/onap/cps/impl/CpsQueryServiceImpl.java
@@ -67,8 +67,15 @@ public class CpsQueryServiceImpl implements CpsQueryService {
     @Override
     public <T> Set<T> queryDataLeaf(final String dataspaceName, final String anchorName, final String cpsPath,
                                     final Class<T> targetClass) {
+        return queryDataLeaf(dataspaceName, anchorName, cpsPath, NO_LIMIT, targetClass);
+    }
+
+    @Override
+    public <T> Set<T> queryDataLeaf(final String dataspaceName, final String anchorName, final String cpsPath,
+                                    final int queryResultLimit, final Class<T> targetClass) {
         cpsValidator.validateNameCharacters(dataspaceName, anchorName);
-        return cpsDataPersistenceService.queryDataLeaf(dataspaceName, anchorName, cpsPath, targetClass);
+        return cpsDataPersistenceService.queryDataLeaf(dataspaceName, anchorName, cpsPath, queryResultLimit,
+                targetClass);
     }
 
     @Override
diff --git a/cps-service/src/main/java/org/onap/cps/spi/CpsDataPersistenceService.java b/cps-service/src/main/java/org/onap/cps/spi/CpsDataPersistenceService.java
index 5be5fb0481..b319929e47 100644
--- a/cps-service/src/main/java/org/onap/cps/spi/CpsDataPersistenceService.java
+++ b/cps-service/src/main/java/org/onap/cps/spi/CpsDataPersistenceService.java
@@ -208,10 +208,12 @@ public interface CpsDataPersistenceService {
      * @param dataspaceName          dataspace name
      * @param anchorName             anchor name
      * @param cpsPath                cps path
+     * @param queryResultLimit       limits the number of returned entities (if less than 1 returns all)
      * @param targetClass            class of the expected data type
      * @return a collection of data objects of expected type
      */
-    <T> Set<T> queryDataLeaf(String dataspaceName, String anchorName, String cpsPath, Class<T> targetClass);
+    <T> Set<T> queryDataLeaf(String dataspaceName, String anchorName, String cpsPath, int queryResultLimit,
+                             Class<T> targetClass);
 
     /**
      * Get a datanode by dataspace name and cps path across all anchors.
diff --git a/cps-service/src/test/groovy/org/onap/cps/impl/CpsQueryServiceImplSpec.groovy b/cps-service/src/test/groovy/org/onap/cps/impl/CpsQueryServiceImplSpec.groovy
index 9db4aa4c3e..d581727e40 100644
--- a/cps-service/src/test/groovy/org/onap/cps/impl/CpsQueryServiceImplSpec.groovy
+++ b/cps-service/src/test/groovy/org/onap/cps/impl/CpsQueryServiceImplSpec.groovy
@@ -77,8 +77,8 @@ class CpsQueryServiceImplSpec extends Specification {
         and: 'the CpsValidator is called on the dataspaceName, schemaSetName and anchorName'
             1 * mockCpsValidator.validateNameCharacters(dataspaceName)
         where: 'all fetch descendants options are supported'
-        fetchDescendantsOption << [FetchDescendantsOption.OMIT_DESCENDANTS, FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS,
-                                   FetchDescendantsOption.DIRECT_CHILDREN_ONLY, new FetchDescendantsOption(10)]
+            fetchDescendantsOption << [FetchDescendantsOption.OMIT_DESCENDANTS, FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS,
+                                       FetchDescendantsOption.DIRECT_CHILDREN_ONLY, new FetchDescendantsOption(10)]
     }
 
     def 'Query total anchors for dataspace and cps path.'() {
@@ -91,7 +91,7 @@ class CpsQueryServiceImplSpec extends Specification {
     def 'Query data leaf.'() {
         when: 'a query for a specific leaf is executed'
             objectUnderTest.queryDataLeaf('some-dataspace', 'some-anchor', '/cps-path/@id', Object.class)
-        then: 'solution is not implemented yet'
-            1 * mockCpsDataPersistenceService.queryDataLeaf('some-dataspace', 'some-anchor', '/cps-path/@id', Object.class)
+        then: 'the persistence service is called once with the correct parameters'
+            1 * mockCpsDataPersistenceService.queryDataLeaf('some-dataspace', 'some-anchor', '/cps-path/@id', 0, Object.class)
     }
 }