From 52800710a294e32ebda6ba8a224fe85d289bfa0f Mon Sep 17 00:00:00 2001
From: Kasper Fabricius Kristensen
 <45367945+kasperkristensen@users.noreply.github.com>
Date: Tue, 14 Nov 2023 21:48:10 +0100
Subject: [PATCH] fix(medusa): Error handling middleware should be applied when
 no config is exported (#5634)

**What**
- Fixes an issue where the default errorHandler middleware was not applied if the user did not have a `middlewares.ts` file.
- Updates the type of `MiddlewaresConfig` so `middlewares` is now optional, as people might want to only set a bodyParser config for a matcher and not provide any additional middleware.
---
 .changeset/smooth-baboons-repeat.md                  |  5 +++++
 packages/medusa/src/loaders/helpers/routing/index.ts | 11 +++++------
 packages/medusa/src/loaders/helpers/routing/types.ts |  2 +-
 3 files changed, 11 insertions(+), 7 deletions(-)
 create mode 100644 .changeset/smooth-baboons-repeat.md

diff --git a/.changeset/smooth-baboons-repeat.md b/.changeset/smooth-baboons-repeat.md
new file mode 100644
index 0000000000..6cd6e44ac1
--- /dev/null
+++ b/.changeset/smooth-baboons-repeat.md
@@ -0,0 +1,5 @@
+---
+"@medusajs/medusa": patch
+---
+
+fix(medusa): Ensure that errorHandler middleware is applied if no middleware config exists
diff --git a/packages/medusa/src/loaders/helpers/routing/index.ts b/packages/medusa/src/loaders/helpers/routing/index.ts
index fc3dd89b4f..3dd53092d0 100644
--- a/packages/medusa/src/loaders/helpers/routing/index.ts
+++ b/packages/medusa/src/loaders/helpers/routing/index.ts
@@ -653,12 +653,7 @@ export class RoutesLoader {
    */
   applyErrorHandlerMiddleware(): void {
     const middlewareDescriptor = this.globalMiddlewaresDescriptor
-
-    if (!middlewareDescriptor) {
-      return
-    }
-
-    const errorHandlerFn = middlewareDescriptor.config?.errorHandler
+    const errorHandlerFn = middlewareDescriptor?.config?.errorHandler
 
     /**
      * If the user has opted out of the error handler then return
@@ -740,6 +735,10 @@ export class RoutesLoader {
      */
 
     for (const route of routes) {
+      if (!route.middlewares || !route.middlewares.length) {
+        continue
+      }
+
       const methods = (
         Array.isArray(route.method) ? route.method : [route.method]
       ).filter(Boolean) as MiddlewareVerb[]
diff --git a/packages/medusa/src/loaders/helpers/routing/types.ts b/packages/medusa/src/loaders/helpers/routing/types.ts
index 3a71c2fba1..d5521f9009 100644
--- a/packages/medusa/src/loaders/helpers/routing/types.ts
+++ b/packages/medusa/src/loaders/helpers/routing/types.ts
@@ -65,7 +65,7 @@ export type MiddlewareRoute = {
   method?: MiddlewareVerb | MiddlewareVerb[]
   matcher: string | RegExp
   bodyParser?: ParserConfig
-  middlewares: MiddlewareFunction[]
+  middlewares?: MiddlewareFunction[]
 }
 
 export type MiddlewaresConfig = {