Merge pull request #333 from IBM/johntimm-master

Issue #329 - skip resource query if pageSize == 0

Author: JohnTimm

fhir-persistence-jdbc/src/main/java/com/ibm/fhir/persistence/jdbc/impl/FHIRPersistenceJDBCImpl.java

@@ -426,8 +426,8 @@ public MultiResourceResult<Resource> search(FHIRPersistenceContext context, Clas
                     }
                 }
 
-                // For _summary=count, we don't need to return any resource
-                if (searchResultCount > 0 && !SummaryValueSet.COUNT.equals(searchContext.getSummaryParameter())) {
+                // For _summary=count or pageSize == 0, we return only the count
+                if (searchResultCount > 0 && !SummaryValueSet.COUNT.equals(searchContext.getSummaryParameter()) && searchContext.getPageSize() > 0) {
                     query = queryBuilder.buildQuery(resourceType, searchContext);
 
                     List<String> elements = searchContext.getElementsParameters();
@@ -749,7 +749,8 @@ public <T extends Resource> MultiResourceResult<T> history(FHIRPersistenceContex
     }
 
     /**
-     * Validate pageSize and pageNumber in the FHIRPagingContext and update invalid paging context parameters.
+     * Validate pageSize and pageNumber in the FHIRPagingContext instance and update 
+     * paging context parameters accordingly.
      * 
      * @param pagingContext
      *     the FHIRPagingContext instance (FHIRSearchContext or FHIRHistoryContext)

fhir-persistence/src/test/java/com/ibm/fhir/persistence/test/common/AbstractPagingTest.java

@@ -228,6 +228,21 @@ public void testHistoryPaging() throws Exception {
         assertEquals(outcome.getIssue().get(0).getCode(), IssueType.INVALID);
     }
 
+    public void testPageSizeEqualsZero() throws Exception {
+        Map<String, List<String>> queryParameters;
+        queryParameters = new HashMap<>();
+        queryParameters.put("_sort", Collections.singletonList("integer"));
+        queryParameters.put("_tag", Collections.singletonList("pagingTest"));
+        queryParameters.put("_page", Collections.singletonList("1"));
+        queryParameters.put("_count", Collections.singletonList("0"));
+        FHIRSearchContext searchContext = SearchUtil.parseQueryParameters(Basic.class, queryParameters);
+        searchContext.setLenient(true);
+        MultiResourceResult<Resource> result = runQueryTest(searchContext, Basic.class, queryParameters, 1);
+        assertTrue(result.isSuccess());
+        assertTrue(result.getResource().isEmpty());
+        assertTrue(result.getOutcome() == null);
+    }
+    
     @Test
     public void testInvalidPage0() throws Exception {
         Map<String, List<String>> queryParameters;

fhir-server/src/main/java/com/ibm/fhir/server/resources/FHIRResource.java

@@ -3875,10 +3875,13 @@ private Boolean isUpdateCreateEnabled() {
 
     private Bundle addLinks(FHIRPagingContext context, Bundle bundle, String requestUri) {
         String selfUri = null;
+        SummaryValueSet summaryParameter = null;
         Bundle.Builder bundleBuilder = bundle.toBuilder();
         if (context instanceof FHIRSearchContext) {
+            FHIRSearchContext searchContext = (FHIRSearchContext) context;
+            summaryParameter = searchContext.getSummaryParameter();
             try {
-                selfUri = SearchUtil.buildSearchSelfUri(requestUri, (FHIRSearchContext) context);
+                selfUri = SearchUtil.buildSearchSelfUri(requestUri, searchContext);
             } catch (Exception e) {
                 log.log(Level.WARNING, "Unable to construct self link for search result bundle; using the request URI instead.", e);
             }
@@ -3891,10 +3894,8 @@ private Bundle addLinks(FHIRPagingContext context, Bundle bundle, String request
                 Bundle.Link.builder().relation(string("self")).url(Url.of(selfUri)).build();
         bundleBuilder.link(selfLink);
 
-        // If for search with _summary=count, then don't add previous and next links.
-        if (!(context instanceof FHIRSearchContext 
-                && ((FHIRSearchContext) context).getSummaryParameter() != null
-                && ((FHIRSearchContext) context).getSummaryParameter().equals(SummaryValueSet.COUNT))) {
+        // If for search with _summary=count or pageSize == 0, then don't add previous and next links.
+        if (!SummaryValueSet.COUNT.equals(summaryParameter) && context.getPageSize() > 0) {
             int nextPageNumber = context.getPageNumber() + 1;
             if (nextPageNumber <= context.getLastPageNumber()) {