[Developer] #424 speed up permission object selection

src/main/java/com/cloudhandson/vpdbackoffice/config/DbPoolWarmup.java

@@ -0,0 +1,50 @@
+package com.cloudhandson.vpdbackoffice.config;
+
+import com.cloudhandson.vpdbackoffice.service.PermissionService;
+import com.cloudhandson.vpdbackoffice.service.ProtectedObjectService;
+import java.sql.Connection;
+import javax.sql.DataSource;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+public class DbPoolWarmup {
+
+  private static final Logger log = LoggerFactory.getLogger(DbPoolWarmup.class);
+  private final DataSource dataSource;
+  private final ProtectedObjectService protectedObjectService;
+  private final PermissionService permissionService;
+
+  public DbPoolWarmup(
+      DataSource dataSource,
+      ProtectedObjectService protectedObjectService,
+      PermissionService permissionService
+  ) {
+    this.dataSource = dataSource;
+    this.protectedObjectService = protectedObjectService;
+    this.permissionService = permissionService;
+  }
+
+  @EventListener(ApplicationReadyEvent.class)
+  public void warmup() {
+    try (Connection ignored = dataSource.getConnection()) {
+      log.info("Backoffice DB pool warmed up");
+      warmupBackofficeCatalog();
+    } catch (Exception exception) {
+      log.warn("Backoffice DB pool warm-up failed: {}", exception.getMessage());
+    }
+  }
+
+  private void warmupBackofficeCatalog() {
+    long started = System.nanoTime();
+    var objects = protectedObjectService.findEnabled();
+    objects.forEach(object -> protectedObjectService.findColumns(object.objectId()));
+    protectedObjectService.findDatabaseObjects();
+    permissionService.findRoles();
+    permissionService.findPermissionViews();
+    log.info("Backoffice DB catalog cache warmed up in {}ms", (System.nanoTime() - started) / 1_000_000);
+  }
+}