Fix potential Invalid state. Transaction has already started in `Re…

…positoryMetaAnalyzerTask`

The task works in such a way that a single `QueryManager` (and thus DN `ExecutionContext` and associated transaction) is shared across analyses of multiple components. Failure to analyze one component does not abort the overall analysis for all components.

Due to missing transaction rollbacks, the `RepositoryMetaAnalyzerTask` could end up in a situation where the `QueryManager`s active transaction failed to commit for one component, such that persisting of results for all following components would fail with `NucleusTransactionException: Invalid state. Transaction has already started`.

This fix is a mere workaround for the missing rollback of the `persist` method. DependencyTrack#2677 has been raised to address this for the entire application.

Signed-off-by: nscuro <nscuro@protonmail.com>

src/main/java/org/dependencytrack/persistence/QueryManager.java

@@ -1315,6 +1315,23 @@ public void runInTransaction(final Runnable runnable) {
         }
     }
 
+    /**
+     * Convenience method to ensure that any active transaction is rolled back.
+     * <p>
+     * Calling this method may sometimes be necessary due to {@link AlpineQueryManager#persist(Object)}
+     * no performing a rollback in case committing the transaction fails. This can impact other persistence
+     * operations performed in the same session (e.g. {@code NucleusTransactionException: Invalid state. Transaction has already started}).
+     *
+     * @see <a href="https://github.com/DependencyTrack/dependency-track/issues/2677">Issue 2677</a>
+     * @since 4.8.0
+     */
+    public void ensureNoActiveTransaction() {
+        final Transaction trx = pm.currentTransaction();
+        if (trx != null && trx.isActive()) {
+            trx.rollback();
+        }
+    }
+
     public void recursivelyDeleteTeam(Team team) {
         pm.setProperty("datanucleus.query.sql.allowAll", true);
         final Transaction trx = pm.currentTransaction();

src/main/java/org/dependencytrack/tasks/repositories/RepositoryMetaAnalyzerTask.java

@@ -72,11 +72,9 @@ public class RepositoryMetaAnalyzerTask implements Subscriber {
     /**
      * {@inheritDoc}
      */
-    @SuppressWarnings("unchecked")
     public void inform(final Event e) {
-        if (e instanceof RepositoryMetaEvent) {
+        if (e instanceof final RepositoryMetaEvent event) {
             LOGGER.debug("Analyzing component repository metadata");
-            final RepositoryMetaEvent event = (RepositoryMetaEvent)e;
             // TODO - Remove when https://github.com/DependencyTrack/dependency-track/issues/2110 is implemented
             Timer timer = Timer.builder("repository_meta_analyzer_task")
                     .description("Repository meta analyzer task timer")
@@ -89,6 +87,7 @@ public void inform(final Event e) {
                     // Refreshing the object by querying for it again is preventative
                     LOGGER.info("Performing component repository metadata analysis against " + components.size() + " components");
                     for (final Component component: components) {
+                        qm.ensureNoActiveTransaction(); // Workaround for https://github.com/DependencyTrack/dependency-track/issues/2677
                         analyze(qm, qm.getObjectById(Component.class, component.getId()));
                     }
                     LOGGER.info("Completed component repository metadata analysis against " + components.size() + " components");
@@ -101,6 +100,7 @@ public void inform(final Event e) {
                         final List<Component> components = qm.getAllComponents(project);
                         LOGGER.debug("Performing component repository metadata analysis against " + components.size() + " components in project: " + project.getUuid());
                         for (final Component component: components) {
+                            qm.ensureNoActiveTransaction(); // Workaround for https://github.com/DependencyTrack/dependency-track/issues/2677
                             analyze(qm, component);
                         }
                         LOGGER.debug("Completed component repository metadata analysis against " + components.size() + " components in project: " + project.getUuid());