Issue 1315: Store file preview to database when file preview is created on Item Page load. (#1316)

* Issue ufal/clarin-dspace1315: Store file preview to database when file preview is created on item page load

* assert text improvement

* PR comments: commit context only when any of the file preview is successfully created

* chabge variable name

Author: kuchtiak-ufal

dspace-server-webapp/src/main/java/org/dspace/app/rest/repository/MetadataBitstreamRestRepository.java

@@ -66,8 +66,7 @@ public class MetadataBitstreamRestRepository extends DSpaceRestRepository<Metada
     @SearchRestMethod(name = "byHandle")
     public Page<MetadataBitstreamWrapperRest> findByHandle(@Parameter(value = "handle", required = true) String handle,
                                                            @Parameter(value = "fileGrpType") String fileGrpType,
-                                                           Pageable pageable)
-            throws Exception {
+                                                           Pageable pageable) throws Exception {
         if (StringUtils.isBlank(handle)) {
             throw new DSpaceBadRequestException("handle cannot be null!");
         }
@@ -80,6 +79,8 @@ public Page<MetadataBitstreamWrapperRest> findByHandle(@Parameter(value = "handl
         List<MetadataBitstreamWrapperRest> rs = new ArrayList<>();
         DSpaceObject dso;
 
+        boolean previewContentCreated = false;
+
         try {
             dso = handleService.resolveToObject(context, handle);
         } catch (Exception e) {
@@ -127,6 +128,7 @@ public Page<MetadataBitstreamWrapperRest> findByHandle(@Parameter(value = "handl
                                     for (FileInfo fi : fileInfos) {
                                         previewContentService.createPreviewContent(context, bitstream, fi);
                                     }
+                                    previewContentCreated = true;
                                 }
                             }
                         } else {
@@ -147,6 +149,11 @@ public Page<MetadataBitstreamWrapperRest> findByHandle(@Parameter(value = "handl
             }
         }
 
+        // commit changes if any preview content was generated
+        if (previewContentCreated) {
+            context.commit();
+        }
+
         return new PageImpl<>(rs, pageable, rs.size());
     }
 

dspace-server-webapp/src/test/java/org/dspace/app/rest/MetadataBitstreamRestRepositoryIT.java

@@ -12,6 +12,7 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
@@ -84,16 +85,16 @@ public void setup() throws Exception {
                 .build();
 
         // create empty THUMBNAIL bundle
-        bundleService.create(context, publicItem, "THUMBNAIL");
-
-        String bitstreamContent = "ThisIsSomeDummyText";
-        InputStream is = IOUtils.toInputStream(bitstreamContent, CharEncoding.UTF_8);
-        bts = BitstreamBuilder.
-                createBitstream(context, publicItem, is)
-                .withName("Bitstream")
-                .withDescription("Description")
-                .withMimeType("application/x-gzip")
-                .build();
+        bundleService.create(context, publicItem, "ORIGINAL");
+
+        try (InputStream is = getClass().getResourceAsStream("assetstore/logos.tgz")) {
+            bts = BitstreamBuilder.
+                    createBitstream(context, publicItem, is)
+                    .withName("Bitstream")
+                    .withDescription("Description")
+                    .withMimeType("application/x-gtar")
+                    .build();
+        }
 
         // Allow composing of file preview in the config
         configurationService.setProperty("create.file-preview.on-item-page-load", true);
@@ -116,6 +117,8 @@ public void findByHandle() throws Exception {
         // There is no restriction, so the user could preview the file
         boolean canPreview = true;
 
+        assertFalse("Expects preview content not created yet.", previewContentService.hasPreview(context, bts));
+
         getClient().perform(get(METADATABITSTREAM_SEARCH_BY_HANDLE_ENDPOINT)
                         .param("handle", publicItem.getHandle())
                         .param("fileGrpType", FILE_GRP_TYPE))
@@ -135,13 +138,13 @@ public void findByHandle() throws Exception {
                         .value(hasItem(is((int) bts.getSizeBytes()))))
                 .andExpect(jsonPath("$._embedded.metadatabitstreams[*].canPreview")
                         .value(Matchers.containsInAnyOrder(Matchers.is(canPreview))))
-                .andExpect(jsonPath("$._embedded.metadatabitstreams[*].fileInfo").exists())
+                .andExpect(jsonPath("$._embedded.metadatabitstreams[0].fileInfo").value(Matchers.hasSize(2)))
                 .andExpect(jsonPath("$._embedded.metadatabitstreams[*].checksum")
                         .value(Matchers.containsInAnyOrder(Matchers.containsString(bts.getChecksum()))))
                 .andExpect(jsonPath("$._embedded.metadatabitstreams[*].href")
                         .value(Matchers.containsInAnyOrder(Matchers.containsString(url))));
 
-
+        assertTrue("Expects preview content created and stored.", previewContentService.hasPreview(context, bts));
     }
 
     @Test