Pass log to GraphStoreCatalog on dbms startup

The log is used to warn if a listener fails

Author: FlorentinD

core/src/main/java/org/neo4j/gds/core/GdsLogExtension.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.gds.core;
+
+import org.neo4j.annotations.service.ServiceProvider;
+import org.neo4j.gds.compat.Neo4jProxy;
+import org.neo4j.gds.core.loading.GraphStoreCatalog;
+import org.neo4j.kernel.extension.ExtensionFactory;
+import org.neo4j.kernel.extension.ExtensionType;
+import org.neo4j.kernel.extension.context.ExtensionContext;
+import org.neo4j.kernel.lifecycle.Lifecycle;
+import org.neo4j.kernel.lifecycle.LifecycleAdapter;
+import org.neo4j.logging.internal.LogService;
+
+@ServiceProvider
+public class GdsLogExtension extends ExtensionFactory<GdsLogExtension.Dependencies> {
+
+    public GdsLogExtension() {
+        super(ExtensionType.GLOBAL, "gds.log");
+    }
+
+    @Override
+    public Lifecycle newInstance(ExtensionContext context, Dependencies dependencies) {
+        return LifecycleAdapter.onInit(() -> {
+            var log = Neo4jProxy.getUserLog(dependencies.logService(), GdsLogExtension.class);
+            GraphStoreCatalog.setLog(log);
+        });
+    }
+
+    interface Dependencies {
+        LogService logService();
+    }
+}

core/src/main/java/org/neo4j/gds/core/loading/GraphStoreCatalog.java

@@ -26,9 +26,11 @@
 import org.neo4j.gds.api.GraphStore;
 import org.neo4j.gds.config.GraphProjectConfig;
 import org.neo4j.gds.utils.StringJoining;
+import org.neo4j.logging.Log;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Optional;
@@ -45,6 +47,10 @@ public final class GraphStoreCatalog {
 
     private static final List<GraphStoreCatalogListener> listeners = new ArrayList<>();
 
+    // as we want to use the Neo4j log if possible and the catalog is a static instance,
+    // we make the log injectable
+    private static Optional<Log> log = Optional.empty();
+
     private GraphStoreCatalog() { }
 
     public static void registerListener(GraphStoreCatalogListener listener) {
@@ -55,6 +61,10 @@ public static void unregisterListener(GraphStoreCatalogListener listener) {
         listeners.remove(listener);
     }
 
+    public static void setLog(Log log) {
+        GraphStoreCatalog.log = Optional.of(log);
+    }
+
     public static GraphStoreWithConfig get(CatalogRequest request, String graphName) {
         var userCatalogKey = UserCatalog.UserCatalogKey.of(request.databaseName(), graphName);
         var ownCatalog = getUserCatalog(request.username());
@@ -174,7 +184,18 @@ private static void set(GraphProjectConfig config, GraphStore graphStore, boolea
             return userCatalog;
         });
 
-        listeners.forEach(listener -> listener.onProject(config.username(), config.graphName()));
+        listeners.forEach(listener -> {
+            try {
+                listener.onProject(config.username(), config.graphName());
+            } catch (Exception e) {
+                log.ifPresent(l -> l.warn(String.format(
+                    Locale.US,
+                    "Could not call listener %s on setting the graph %s",
+                    listener,
+                    config.graphName()
+                ), e));
+            }
+        });
     }
 
     public static boolean exists(String username, String databaseName, String graphName) {