From db405d243c1f0913c9bfa698a24fc076e7ede933 Mon Sep 17 00:00:00 2001
From: Michael Olorunnisola <michael.olorunnisola@elastic.co>
Date: Mon, 2 Feb 2026 17:51:27 -0500
Subject: [PATCH] [Cases][Webhook] - Better handle 204 responses (#251090)

## Summary

Currently when an update is made to an external connector that returns a
`204` no content response, the rest of the incident update fails. This
should not occur as a 204 is a valid response

Fixes https://github.com/elastic/kibana/issues/251108

### Checklist

Check the PR satisfies following conditions.

- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

(cherry picked from commit 926e3a2ea37ef37f0a2faed96c241a8179901a24)
---
 .../cases_webhook/service.test.ts             | 42 +++++++++++++++++++
 .../cases_webhook/utils.test.ts               | 26 ++++++++++++
 .../connector_types/cases_webhook/utils.ts    |  5 +++
 3 files changed, 73 insertions(+)

diff --git a/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/service.test.ts b/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/service.test.ts
index b3cc82a68554e..bbf48a457b645 100644
--- a/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/service.test.ts
+++ b/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/service.test.ts
@@ -1354,6 +1354,48 @@ describe('Cases webhook service', () => {
         '[Action][Webhook - Case Management]: Unable to update case with id 1. Error: Unsupported content type: text/html in GET https://example.com. Supported content types: application/json.'
       );
     });
+
+    it('it should throw if the request status is a 204 and has data', async () => {
+      requestMock.mockImplementation(() =>
+        createAxiosResponse({
+          data: 'some data',
+          headers: { ['content-type']: 'text/html' },
+          status: 204,
+        })
+      );
+
+      await expect(service.updateIncident(incident)).rejects.toThrow(
+        '[Action][Webhook - Case Management]: Unable to update case with id 1. Error: Unsupported content type: text/html in GET https://example.com. Supported content types: application/json.'
+      );
+    });
+
+    it('it should NOT throw if the request status is a 204 and is empty', async () => {
+      // Initial mock for the update call
+      requestMock.mockImplementationOnce(() =>
+        createAxiosResponse({
+          data: undefined,
+          headers: { ['content-type']: 'text/html' },
+          status: 204,
+        })
+      );
+
+      // Second mock for the getIncident call inside updateIncident
+      requestMock.mockImplementationOnce(() =>
+        createAxiosResponse({
+          data: {
+            id: '1',
+            key: 'CK-1',
+          },
+        })
+      );
+
+      await expect(service.updateIncident(incident)).resolves.toEqual({
+        id: '1',
+        title: 'CK-1',
+        pushedDate: mockTime.toISOString(),
+        url: 'https://coolsite.net/browse/CK-1',
+      });
+    });
   });
 
   describe('createComment', () => {
diff --git a/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.test.ts b/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.test.ts
index 8e73e1d6682fd..a069e11869fb4 100644
--- a/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.test.ts
+++ b/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.test.ts
@@ -64,6 +64,32 @@ describe('cases_webhook/utils', () => {
         headers: new AxiosHeaders({}),
       },
     };
+
+    it('Does not throw when the response status is 204 and there is no data', () => {
+      expect(() =>
+        throwDescriptiveErrorIfResponseIsNotValid({
+          res: {
+            ...res,
+            status: 204,
+            data: undefined,
+          },
+        })
+      ).not.toThrow();
+    });
+
+    it('Throws when the response status is 204 and requiredAttributesToBeInTheResponse is set', () => {
+      expect(() =>
+        throwDescriptiveErrorIfResponseIsNotValid({
+          res: {
+            ...res,
+            status: 204,
+            data: undefined,
+          },
+          requiredAttributesToBeInTheResponse: ['field.simple'],
+        })
+      ).toThrow();
+    });
+
     it('Throws error when missing content-type', () => {
       expect(() =>
         throwDescriptiveErrorIfResponseIsNotValid({
diff --git a/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.ts b/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.ts
index 2a13e35a375a9..753915de24833 100644
--- a/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.ts
+++ b/x-pack/platform/plugins/shared/stack_connectors/server/connector_types/cases_webhook/utils.ts
@@ -43,6 +43,11 @@ export const throwDescriptiveErrorIfResponseIsNotValid = ({
   const contentType = res.headers['content-type'];
   const data = res.data;
 
+  // If status is 204 and there is no data, we just return
+  if (res.status === 204 && isEmpty(data) && requiredAttributesToBeInTheResponse.length === 0) {
+    return;
+  }
+
   /**
    * Check that the content-type of the response is application/json.
    * Then includes is added because the header can be application/json;charset=UTF-8.