fix: concurrent issue when bulk-generate with db lock retry and change concurrent to for loop for db lock safe thread.

packages/core/server/services/bulk-generate.ts

@@ -3,6 +3,53 @@ import { UID } from '@strapi/strapi';
 import { getPluginService } from '../util/getPluginService';
 import { GenerationType } from '../types';
 
+// Helper function to safely extract error message
+function getErrorMessage(err: unknown): string {
+  if (typeof err === 'object' && err && 'message' in err) {
+    const { message } = err as { message?: unknown };
+    if (typeof message === 'string') {
+      return message.toLowerCase();
+    }
+  }
+  return '';
+}
+
+// Deadlock/locking retry helper for all major DBs
+async function withDbLockRetry<T>(
+  fn: () => Promise<T>,
+  retries = 3,
+  delay = 100,
+): Promise<T | undefined> {
+  for (let i = 0; i < retries; i++) {
+    try {
+      // eslint-disable-next-line no-await-in-loop
+      const result = await fn();
+      return result;
+    } catch (err: unknown) {
+      // Safe type guard
+      const msg: string = getErrorMessage(err);
+      // Covers MySQL/MariaDB/Postgres/SQLite
+      if (
+        (
+          msg.includes('deadlock') || // MySQL, MariaDB, Postgres
+          msg.includes('could not serialize access') || // Postgres
+          msg.includes('lock wait timeout') || // MySQL, MariaDB
+          msg.includes('database is locked') // SQLite
+        ) && i < retries - 1
+      ) {
+        // eslint-disable-next-line no-await-in-loop
+        await new Promise<void>((resolve) => { setTimeout(resolve, delay); });
+        // continue is intentional and allowed here
+        // eslint-disable-next-line no-continue
+        continue;
+      }
+      throw err;
+    }
+  }
+  // If all retries exhausted, throw an error (this satisfies consistent-return)
+  throw new Error('withDbLockRetry: operation failed after max retries');
+}
+
 export interface GenerateParams {
   types: UID.ContentType[],
   generationType: GenerationType,
@@ -18,30 +65,35 @@ const generateUrlAliases = async (params: GenerateParams): Promise<number> => {
   const { types, generationType } = params;
   let generatedCount = 0;
 
-  // Map over all the types sent in the request.
-  await Promise.all(types.map(async (type) => {
+  // No concurrency: process each type one by one
+  // eslint-disable-next-line no-restricted-syntax
+  for (const type of types) {
+    // Lock-safe delete operations
     if (generationType === 'all') {
       // Delete all the URL aliases for the given type.
-      await strapi.db.query('plugin::webtools.url-alias').deleteMany({
+      // eslint-disable-next-line no-await-in-loop
+      await withDbLockRetry(() => strapi.db.query('plugin::webtools.url-alias').deleteMany({
         where: { contenttype: type },
-      });
+      }));
     }
 
     if (generationType === 'only_generated') {
       // Delete all the auto generated URL aliases of the given type.
-      await strapi.db.query('plugin::webtools.url-alias').deleteMany({
+      // eslint-disable-next-line no-await-in-loop
+      await withDbLockRetry(() => strapi.db.query('plugin::webtools.url-alias').deleteMany({
         where: { contenttype: type, generated: true },
-      });
+      }));
     }
 
     let relations: string[] = [];
-    let languages: string[] = [undefined];
+    let languages: string[] = [];
 
-    languages = [];
+    // eslint-disable-next-line no-await-in-loop
     const locales = await strapi.documents('plugin::i18n.locale').findMany({});
     languages = locales.map((locale) => locale.code);
 
     // Get all relations for the type
+    // eslint-disable-next-line no-await-in-loop
     await Promise.all(languages.map(async (lang) => {
       const urlPatterns = await getPluginService('url-pattern').findByUid(type, lang);
       urlPatterns.forEach((urlPattern) => {
@@ -51,6 +103,7 @@ const generateUrlAliases = async (params: GenerateParams): Promise<number> => {
     }));
 
     // Query all the entities of the type that do not have a corresponding URL alias.
+    // eslint-disable-next-line no-await-in-loop
     const entities = await strapi.documents(type as 'api::test.test').findMany({
       filters: { url_alias: null },
       populate: {
@@ -77,29 +130,30 @@ const generateUrlAliases = async (params: GenerateParams): Promise<number> => {
       const resolvedPath = getPluginService('url-pattern').resolvePattern(type, entity, urlPatterns[0]);
 
       // eslint-disable-next-line no-await-in-loop
-      const newUrlAlias = await strapi.documents('plugin::webtools.url-alias').create({
+      const newUrlAlias = await withDbLockRetry(() => strapi.documents('plugin::webtools.url-alias').create({
         data: {
           url_path: resolvedPath,
           generated: true,
           contenttype: type,
           locale: entity.locale,
         },
-      });
+      }));
 
       // eslint-disable-next-line no-await-in-loop
-      await strapi.documents(type as 'api::test.test').update({
+      await withDbLockRetry(() => strapi.documents(type as 'api::test.test').update({
         documentId: entity.documentId,
         data: {
           url_alias: [newUrlAlias.documentId],
         },
-      });
+      }));
 
+      // Safe parallel localizations—OK for a handful of locales
       // eslint-disable-next-line no-await-in-loop
       await Promise.all(entity.localizations.map(async (loc) => {
         const patterns = await getPluginService('url-pattern').findByUid(type, loc.locale);
         const path = getPluginService('url-pattern').resolvePattern(type, loc, patterns[0]);
 
-        const alias = await strapi.documents('plugin::webtools.url-alias').update({
+        const alias = await withDbLockRetry(() => strapi.documents('plugin::webtools.url-alias').update({
           documentId: newUrlAlias.documentId,
           locale: loc.locale,
           data: {
@@ -108,20 +162,20 @@ const generateUrlAliases = async (params: GenerateParams): Promise<number> => {
             contenttype: type,
             locale: entity.locale,
           },
-        });
+        }));
 
-        await strapi.documents(type as 'api::test.test').update({
+        await withDbLockRetry(() => strapi.documents(type as 'api::test.test').update({
           documentId: entity.documentId,
           locale: loc.locale,
           data: {
             url_alias: [alias.documentId],
           },
-        });
+        }));
       }));
 
       generatedCount += 1;
     }
-  }));
+  }
 
   return generatedCount;
 };