From c6b9bc057f7432c598163c93bbdbe930c14a8456 Mon Sep 17 00:00:00 2001
From: Fadhlaoui Raed <raed.fadhlaoui@hotmail.com>
Date: Mon, 2 Nov 2026 20:35:30 -0500
Subject: [PATCH] fix: parse application/*+json request bodies as JSON

The default JSON parser was registered without a type, so body-parser
matched only application/json. Bodies sent with a structured syntax
suffix type, such as application/vnd.api+json (required by JSON:API) or
application/merge-patch+json, fell through to the raw parser and reached
the function as a Buffer.

Give the JSON parser its own options with
type ['application/json', 'application/*+json']. The CloudEvents parser
still runs first for application/cloudevents+json, and the text parser
keeps its existing options.

Fixes #809
---
 src/server.ts            |  9 ++++++++-
 test/integration/http.ts | 14 ++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/server.ts b/src/server.ts
index 7710088d1..72f2b6722 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -69,6 +69,13 @@ export function getServer(
     limit: requestLimit,
     verify: rawBodySaver,
   };
+  // Parse structured syntax suffix types such as application/vnd.api+json as
+  // JSON too (RFC 6839). application/cloudevents+json is matched by the
+  // CloudEvents parser first.
+  const jsonBodySavingOptions = {
+    ...defaultBodySavingOptions,
+    type: ['application/json', 'application/*+json'],
+  };
   const cloudEventsBodySavingOptions = {
     type: 'application/cloudevents+json',
     limit: requestLimit,
@@ -89,7 +96,7 @@ export function getServer(
 
   // Apply middleware
   app.use(bodyParser.json(cloudEventsBodySavingOptions));
-  app.use(bodyParser.json(defaultBodySavingOptions));
+  app.use(bodyParser.json(jsonBodySavingOptions));
   app.use(bodyParser.text(defaultBodySavingOptions));
   app.use(bodyParser.urlencoded(urlEncodedOptions));
   // The parser will process ALL content types so MUST come last.
diff --git a/test/integration/http.ts b/test/integration/http.ts
index ec78d4f91..400eaf11e 100644
--- a/test/integration/http.ts
+++ b/test/integration/http.ts
@@ -117,4 +117,18 @@ describe('HTTP Function', () => {
       assert.strictEqual(callCount, test.expectedCallCount);
     });
   });
+
+  ['application/vnd.api+json', 'application/merge-patch+json'].forEach(
+    contentType => {
+      it(`parses a ${contentType} body as JSON`, async () => {
+        const response = await supertest(getTestServer('testHttpFunction'))
+          .post('/')
+          .set('Content-Type', contentType)
+          .send(JSON.stringify({text: 'hello'}));
+
+        assert.deepStrictEqual(response.body, {result: 'hello'});
+        assert.strictEqual(response.status, 200);
+      });
+    },
+  );
 });