Iss #30 - Update DAO to use safer deletion call, add DAO tests

Resolves #30 (closed)

persistence/runtime/src/main/java/org/eclipsefoundation/persistence/dao/impl/BaseHibernateDao.java

@@ -44,6 +44,8 @@ import org.slf4j.LoggerFactory;
 public abstract class BaseHibernateDao implements PersistenceDao {
     private static final Logger LOGGER = LoggerFactory.getLogger(BaseHibernateDao.class);
 
+    private static final int DEFAULT_MAX_LIMIT = 1000;
+
     @Inject
     EntityManager primaryConnectionManager;
 
@@ -73,20 +75,12 @@ public abstract class BaseHibernateDao implements PersistenceDao {
                 query = query.setFirstResult(getOffset(q)).setMaxResults(getLimit(q));
             }
         }
-
-        // add ordinal parameters
-        int ord = 1;
-        for (Clause c : q.getFilter().getClauses()) {
-            for (Object param : c.getParams()) {
-                // for each of params, if processing call statement, add params as registered params
-                if (q.getFilter() instanceof ParameterizedCallStatement) {
-                    ((StoredProcedureQuery) query).registerStoredProcedureParameter(ord, param.getClass(), ParameterMode.IN);
-                }
-                query.setParameter(ord++, param);
-            }
-        }
-        // run the query
-        return castResultsToType(query.getResultList(), q.getDocType());
+        // update ordinals for the request
+        handleOrdinals(q, query);
+        // run the query and detach the results (stability w/ hibernate contexts)
+        List<T> results = castResultsToType(query.getResultList(), q.getDocType());
+        results.forEach(r -> getSecondaryEntityManager().detach(r));
+        return results;
     }
 
     @Transactional
@@ -136,8 +130,8 @@ public abstract class BaseHibernateDao implements PersistenceDao {
         EntityManager em = getPrimaryEntityManager();
         List<T> results = get(q);
         if (results != null) {
-            // remove all matched documents
-            results.forEach(em::remove);
+            // remove all matched documents, merging to ensure we have attached versions (transaction barriers sometimes break)
+            results.forEach(r -> em.remove(em.merge(r)));
         }
     }
 
@@ -154,13 +148,7 @@ public abstract class BaseHibernateDao implements PersistenceDao {
 
         // build base query
         TypedQuery<Long> query = em.createQuery(q.getFilter().getCountSql(), Long.class);
-        // add ordinal parameters
-        int ord = 1;
-        for (Clause c : q.getFilter().getClauses()) {
-            for (Object param : c.getParams()) {
-                query.setParameter(ord++, param);
-            }
-        }
+        handleOrdinals(q, query);
         return query.getSingleResult();
     }
 
@@ -182,13 +170,53 @@ public abstract class BaseHibernateDao implements PersistenceDao {
         q.getWrapper().setHeader(PaginatedResultsFilter.MAX_PAGE_SIZE_HEADER, Integer.toString(getLimit(q)));
     }
 
+    /**
+     * Handle adding ordinals from the wrapped query param object into the base query to be sent to db.
+     * 
+     * @param q the wrapped query params for the current request
+     * @param actualQuery the actual DB query to be passed to the entity manager
+     */
+    private void handleOrdinals(RDBMSQuery<?> q, Query actualQuery) {
+        // add ordinal parameters
+        int ord = 1;
+        for (Clause c : q.getFilter().getClauses()) {
+            for (Object param : c.getParams()) {
+                // for each of params, if processing call statement, add params as registered params
+                if (q.getFilter() instanceof ParameterizedCallStatement) {
+                    ((StoredProcedureQuery) actualQuery).registerStoredProcedureParameter(ord, param.getClass(), ParameterMode.IN);
+                }
+                actualQuery.setParameter(ord++, param);
+            }
+        }
+    }
+
+    /**
+     * Get the limit for entities returned in a single bound request.
+     * 
+     * @param q the query params for the current request to check for set limit in params
+     * @return the number of entities allowed
+     */
     private int getLimit(RDBMSQuery<?> q) {
-        return q.getLimit() > 0 ? Math
-                .min(q.getLimit(),
-                        ConfigProvider.getConfig().getOptionalValue("eclipse.db.default.limit", Integer.class).orElseGet(() -> 1000))
-                : ConfigProvider.getConfig().getOptionalValue("eclipse.db.default.limit.max", Integer.class).orElseGet(() -> 1000);
+        return q.getLimit() > 0
+                ? Math
+                        .min(q.getLimit(),
+                                ConfigProvider
+                                        .getConfig()
+                                        .getOptionalValue("eclipse.db.default.limit", Integer.class)
+                                        .orElseGet(() -> DEFAULT_MAX_LIMIT))
+                : ConfigProvider
+                        .getConfig()
+                        .getOptionalValue("eclipse.db.default.limit.max", Integer.class)
+                        .orElseGet(() -> DEFAULT_MAX_LIMIT);
     }
 
+    /**
+     * Get offset cursor for the current request. Uses paging to enable batch requests that match the current max number of
+     * results by URL params.
+     * 
+     * @param q the current requests query parameters, used to check for offset params
+     * @return the offset of the current request, reactive to paging.
+     */
     private int getOffset(RDBMSQuery<?> q) {
         // allow for manual offsetting
         int manualOffset = q.getManualOffset();