From 531ffd6d58e9517da27a9d00a935a5bc805f6de1 Mon Sep 17 00:00:00 2001
From: Mattermost Build <build@mattermost.com>
Date: Thu, 9 Jan 2020 09:35:08 +0100
Subject: [PATCH] Automated cherry pick of #3790 (#3791)

* Handle lower case headers

* Change var name
---
 app/init/fetch.js      | 24 +++++++---------
 app/init/fetch.test.js | 64 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 14 deletions(-)
 create mode 100644 app/init/fetch.test.js

diff --git a/app/init/fetch.js b/app/init/fetch.js
index bb8f2fb14..edd05091e 100644
--- a/app/init/fetch.js
+++ b/app/init/fetch.js
@@ -17,8 +17,8 @@ import {t} from 'app/utils/i18n';
 
 /* eslint-disable no-throw-literal */
 
-const HEADER_X_CLUSTER_ID = 'X-Cluster-Id';
-const HEADER_TOKEN = 'Token';
+export const HEADER_X_CLUSTER_ID = 'X-Cluster-Id';
+export const HEADER_TOKEN = 'Token';
 
 let managedConfig;
 
@@ -99,23 +99,19 @@ Client4.doFetchWithResponse = async (url, options) => {
         });
     }
 
-    if (headers[HEADER_X_CLUSTER_ID] || headers[HEADER_X_CLUSTER_ID.toLowerCase()]) {
-        const clusterId = headers[HEADER_X_CLUSTER_ID] || headers[HEADER_X_CLUSTER_ID.toLowerCase()];
-        if (clusterId && Client4.clusterId !== clusterId) {
-            Client4.clusterId = clusterId; /* eslint-disable-line require-atomic-updates */
-        }
+    const clusterId = headers[HEADER_X_CLUSTER_ID] || headers[HEADER_X_CLUSTER_ID.toLowerCase()];
+    if (clusterId && Client4.clusterId !== clusterId) {
+        Client4.clusterId = clusterId; /* eslint-disable-line require-atomic-updates */
     }
 
-    if (headers[HEADER_TOKEN] || headers[HEADER_TOKEN.toLowerCase()]) {
-        const token = headers[HEADER_TOKEN] || headers[HEADER_TOKEN.toLowerCase()];
+    const token = headers[HEADER_TOKEN] || headers[HEADER_TOKEN.toLowerCase()];
+    if (token) {
         Client4.setToken(token);
     }
 
-    if (headers[HEADER_X_VERSION_ID] && !headers['Cache-Control']) {
-        const serverVersion = headers[HEADER_X_VERSION_ID];
-        if (serverVersion && Client4.serverVersion !== serverVersion) {
-            Client4.serverVersion = serverVersion; /* eslint-disable-line require-atomic-updates */
-        }
+    const serverVersion = headers[HEADER_X_VERSION_ID] || headers[HEADER_X_VERSION_ID.toLowerCase()];
+    if (serverVersion && !headers['Cache-Control'] && Client4.serverVersion !== serverVersion) {
+        Client4.serverVersion = serverVersion; /* eslint-disable-line require-atomic-updates */
     }
 
     if (response.ok) {
diff --git a/app/init/fetch.test.js b/app/init/fetch.test.js
new file mode 100644
index 000000000..316fc53c6
--- /dev/null
+++ b/app/init/fetch.test.js
@@ -0,0 +1,64 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+import {Client4} from 'mattermost-redux/client';
+import {HEADER_X_VERSION_ID} from 'mattermost-redux/client/client4';
+
+import {
+    HEADER_X_CLUSTER_ID,
+    HEADER_TOKEN,
+} from 'app/init/fetch';
+
+describe('Fetch', () => {
+    test('doFetchWithResponse handles empty headers', async () => {
+        const setToken = jest.spyOn(Client4, 'setToken');
+        const response = {
+            json: () => Promise.resolve('data'),
+            headers: {},
+            ok: true,
+        };
+        global.fetch.mockReturnValueOnce(response);
+        await Client4.doFetchWithResponse('https://mattermost.com', {method: 'GET'});
+        expect(Client4.serverVersion).toEqual('');
+        expect(Client4.clusterId).toEqual('');
+        expect(setToken).not.toHaveBeenCalled();
+    });
+
+    test('doFetchWithResponse handles title case headers', async () => {
+        const setToken = jest.spyOn(Client4, 'setToken');
+        const headers = {
+            [HEADER_X_VERSION_ID]: 'VersionId',
+            [HEADER_X_CLUSTER_ID]: 'ClusterId',
+            [HEADER_TOKEN]: 'Token',
+        };
+        const response = {
+            json: () => Promise.resolve('data'),
+            ok: true,
+            headers,
+        };
+        global.fetch.mockReturnValueOnce(response);
+        await Client4.doFetchWithResponse('https://mattermost.com', {method: 'GET'});
+        expect(Client4.serverVersion).toEqual(headers[HEADER_X_VERSION_ID]);
+        expect(Client4.clusterId).toEqual(headers[HEADER_X_CLUSTER_ID]);
+        expect(setToken).toHaveBeenCalledWith(headers[HEADER_TOKEN]);
+    });
+
+    test('doFetchWithResponse handles lower case headers', async () => {
+        const setToken = jest.spyOn(Client4, 'setToken');
+        const headers = {
+            [HEADER_X_VERSION_ID.toLowerCase()]: 'versionid',
+            [HEADER_X_CLUSTER_ID.toLowerCase()]: 'clusterid',
+            [HEADER_TOKEN.toLowerCase()]: 'token',
+        };
+        const response = {
+            json: () => Promise.resolve('data'),
+            ok: true,
+            headers,
+        };
+        global.fetch.mockReturnValueOnce(response);
+        await Client4.doFetchWithResponse('https://mattermost.com', {method: 'GET'});
+        expect(Client4.serverVersion).toEqual(headers[HEADER_X_VERSION_ID.toLowerCase()]);
+        expect(Client4.clusterId).toEqual(headers[HEADER_X_CLUSTER_ID.toLowerCase()]);
+        expect(setToken).toHaveBeenCalledWith(headers[HEADER_TOKEN.toLowerCase()]);
+    });
+});
\ No newline at end of file