steffenr · January 29, 2018 07:23 · Jan 29, 2018
diff --git a/id_map_custom.php b/id_map_custom.php
@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * Implements hook_migration_plugins_alter().
+ */
+function my_module_migration_plugins_alter(array &$migrations) {
+  foreach ($migrations as $id => $configuration) {
+    if (!empty($migrations[$id]['idMap'])) {
+      // Do not override existing values.
+      continue;
+    }
+    // Override id map for each migration.
+    $migrations[$id]['idMap'] = [
+      'plugin' => 'sql_large_key',
+    ];
+  }
+}