Issue #2817833 by Jo Fitzgerald, ckaotik, svendecabooter: Delay sql map table creation

core/modules/migrate/src/Plugin/migrate/id_map/Sql.php

@@ -3,6 +3,7 @@
 namespace Drupal\migrate\Plugin\migrate\id_map;
 
 use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Database\DatabaseException;
 use Drupal\Core\Field\BaseFieldDefinition;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
 use Drupal\Core\Plugin\PluginBase;
@@ -161,6 +162,18 @@ public function __construct(array $configuration, $plugin_id, $plugin_definition
     $this->migration = $migration;
     $this->eventDispatcher = $event_dispatcher;
     $this->message = new MigrateMessage();
+
+    if (!isset($this->database)) {
+      $this->database = \Drupal::database();
+    }
+
+    // Default generated table names, limited to 63 characters.
+    $machine_name = str_replace(':', '__', $this->migration->id());
+    $prefix_length = strlen($this->database->tablePrefix());
+    $this->mapTableName = 'migrate_map_' . Unicode::strtolower($machine_name);
+    $this->mapTableName = Unicode::substr($this->mapTableName, 0, 63 - $prefix_length);
+    $this->messageTableName = 'migrate_message_' . Unicode::strtolower($machine_name);
+    $this->messageTableName = Unicode::substr($this->messageTableName, 0, 63 - $prefix_length);
   }
 
   /**
@@ -246,7 +259,6 @@ protected function destinationIdFields() {
    *   The map table name.
    */
   public function mapTableName() {
-    $this->init();
     return $this->mapTableName;
   }
 
@@ -257,7 +269,6 @@ public function mapTableName() {
    *   The message table name.
    */
   public function messageTableName() {
-    $this->init();
     return $this->messageTableName;
   }
 
@@ -278,9 +289,6 @@ public function getQualifiedMapTableName() {
    *   The database connection object.
    */
   public function getDatabase() {
-    if (!isset($this->database)) {
-      $this->database = \Drupal::database();
-    }
     $this->init();
     return $this->database;
   }
@@ -291,13 +299,6 @@ public function getDatabase() {
   protected function init() {
     if (!$this->initialized) {
       $this->initialized = TRUE;
-      // Default generated table names, limited to 63 characters.
-      $machine_name = str_replace(':', '__', $this->migration->id());
-      $prefix_length = strlen($this->getDatabase()->tablePrefix());
-      $this->mapTableName = 'migrate_map_' . Unicode::strtolower($machine_name);
-      $this->mapTableName = Unicode::substr($this->mapTableName, 0, 63 - $prefix_length);
-      $this->messageTableName = 'migrate_message_' . Unicode::strtolower($machine_name);
-      $this->messageTableName = Unicode::substr($this->messageTableName, 0, 63 - $prefix_length);
       $this->ensureTables();
     }
   }
@@ -696,21 +697,17 @@ public function prepareUpdate() {
    * {@inheritdoc}
    */
   public function processedCount() {
-    return $this->getDatabase()->select($this->mapTableName())
-      ->countQuery()
-      ->execute()
-      ->fetchField();
+    return $this->countHelper(NULL, $this->mapTableName());
   }
 
   /**
    * {@inheritdoc}
    */
   public function importedCount() {
-    return $this->getDatabase()->select($this->mapTableName())
-      ->condition('source_row_status', [MigrateIdMapInterface::STATUS_IMPORTED, MigrateIdMapInterface::STATUS_NEEDS_UPDATE], 'IN')
-      ->countQuery()
-      ->execute()
-      ->fetchField();
+    return $this->countHelper([
+      MigrateIdMapInterface::STATUS_IMPORTED,
+      MigrateIdMapInterface::STATUS_NEEDS_UPDATE,
+    ]);
   }
 
   /**
@@ -737,20 +734,28 @@ public function messageCount() {
   /**
    * Counts records in a table.
    *
-   * @param int $status
-   *   An integer for the source_row_status column.
+   * @param int|array $status
+   *   (optional) Status code(s) to filter the source_row_status column.
    * @param string $table
    *   (optional) The table to work. Defaults to NULL.
    *
    * @return int
    *   The number of records.
    */
-  protected function countHelper($status, $table = NULL) {
-    $query = $this->getDatabase()->select($table ?: $this->mapTableName());
+  protected function countHelper($status = NULL, $table = NULL) {
+    // Use database directly to avoid creating tables.
+    $query = $this->database->select($table ?: $this->mapTableName());
     if (isset($status)) {
-      $query->condition('source_row_status', $status);
+      $query->condition('source_row_status', $status, is_array($status) ? 'IN' : '=');
+    }
+    try {
+      $count = $query->countQuery()->execute()->fetchField();
+    }
+    catch (DatabaseException $e) {
+      // The table does not exist, therefore there are no records.
+      $count = 0;
     }
-    return $query->countQuery()->execute()->fetchField();
+    return $count;
   }
 
   /**

core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php

@@ -1010,4 +1010,23 @@ private function getIdMapContents() {
     return $contents;
   }
 
+  public function testMapTableCreation() {
+    $id_map = $this->getIdMap();
+
+    $map_table_name = $id_map->mapTableName();
+    $message_table_name = $id_map->messageTableName();
+    $this->assertEquals('migrate_map_sql_idmap_test', $map_table_name);
+    $this->assertEquals('migrate_message_sql_idmap_test', $message_table_name);
+
+    // Check that tables don't exist.
+    $this->assertFalse($this->database->schema()->tableExists($map_table_name));
+    $this->assertFalse($this->database->schema()->tableExists($message_table_name));
+
+    $id_map->getDatabase();
+
+    // Check that tables do exist.
+    $this->assertTrue($this->database->schema()->tableExists($map_table_name));
+    $this->assertTrue($this->database->schema()->tableExists($message_table_name));
+  }
+
 }