Move database migration to a premium service

api/src/org/labkey/api/data/DatabaseMigrationService.java

@@ -0,0 +1,90 @@
+package org.labkey.api.data;
+
+import org.apache.logging.log4j.Logger;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.labkey.api.query.TableSorter;
+import org.labkey.api.services.ServiceRegistry;
+import org.labkey.api.util.logging.LogHelper;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+public interface DatabaseMigrationService
+{
+    Logger LOG = LogHelper.getLogger(DatabaseMigrationService.class, "Information about database migration");
+
+    static @NotNull DatabaseMigrationService get()
+    {
+        DatabaseMigrationService ret = ServiceRegistry.get().getService(DatabaseMigrationService.class);
+        return ret != null ? ret : new DatabaseMigrationService() {};
+    }
+
+    static void setInstance(DatabaseMigrationService impl)
+    {
+        ServiceRegistry.get().registerService(DatabaseMigrationService.class, impl);
+    }
+
+    // By default, no-op implementation that simply logs
+    default void migrate(boolean shouldInsertData, @Nullable String migrationDataSource)
+    {
+        LOG.warn("Database migration service is not present; database migration is a premium feature.");
+    }
+
+    // By default, no-op implementation
+    default void registerHandler(DbSchema schema, MigrationHandler handler) {}
+
+    interface MigrationHandler
+    {
+        void beforeVerification(DbSchema targetSchema);
+
+        void beforeSchema(DbSchema targetSchema);
+
+        List<TableInfo> getTablesToCopy(DbSchema targetSchema);
+
+        void afterSchema(DbSchema targetSchema);
+    }
+
+    class DefaultMigrationHandler implements MigrationHandler
+    {
+        @Override
+        public void beforeVerification(DbSchema targetSchema)
+        {
+        }
+
+        @Override
+        public void beforeSchema(DbSchema targetSchema)
+        {
+        }
+
+        @Override
+        public List<TableInfo> getTablesToCopy(DbSchema targetSchema)
+        {
+            Set<TableInfo> sortedTables = new LinkedHashSet<>(TableSorter.sort(targetSchema, true));
+
+            Set<TableInfo> allTables = targetSchema.getTableNames().stream()
+                .map(targetSchema::getTable)
+                .collect(Collectors.toCollection(HashSet::new));
+            allTables.removeAll(sortedTables);
+
+            if (!allTables.isEmpty())
+            {
+                LOG.info("These tables were removed by TableSorter: {}", allTables);
+            }
+
+            return sortedTables.stream()
+                // Skip all views and virtual tables (e.g., test.Containers2, which is a table on SS but a view on PG)
+                .filter(table -> table.getTableType() == DatabaseTableType.TABLE)
+                .collect(Collectors.toCollection(ArrayList::new)); // Ensure mutable
+        }
+
+        @Override
+        public void afterSchema(DbSchema targetSchema)
+        {
+        }
+    }
+}