Add license expiry messages (#3153)

webapp/utils/constants.jsx

@@ -750,5 +750,7 @@ export default {
     MHPNS: 'https://push.mattermost.com',
     MTPNS: 'http://push-test.mattermost.com',
     BOT_NAME: 'BOT',
-    POST_COLLAPSE_TIMEOUT: 1000 * 60 * 5 // five minutes
+    POST_COLLAPSE_TIMEOUT: 1000 * 60 * 5, // five minutes
+    LICENSE_EXPIRY_NOTIFICATION: 1000 * 60 * 60 * 24 * 15, // 15 days
+    LICENSE_GRACE_PERIOD: 1000 * 60 * 60 * 24 * 15 // 15 days
 };

webapp/utils/license_utils.jsx

@@ -0,0 +1,45 @@
+// Copyright (c) 2016 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+import Constants from 'utils/constants.jsx';
+
+import React from 'react';
+import {FormattedDate} from 'react-intl';
+
+export function isLicenseExpiring() {
+    if (window.mm_license.IsLicensed !== 'true') {
+        return false;
+    }
+
+    const timeDiff = parseInt(global.window.mm_license.ExpiresAt, 10) - Date.now();
+    return timeDiff <= Constants.LICENSE_EXPIRY_NOTIFICATION;
+}
+
+export function isLicenseExpired() {
+    if (window.mm_license.IsLicensed !== 'true') {
+        return false;
+    }
+
+    const timeDiff = parseInt(global.window.mm_license.ExpiresAt, 10) - Date.now();
+    return timeDiff < 0;
+}
+
+export function isLicensePastGracePeriod() {
+    if (window.mm_license.IsLicensed !== 'true') {
+        return false;
+    }
+
+    const timeDiff = Date.now() - parseInt(global.window.mm_license.ExpiresAt, 10);
+    return timeDiff > Constants.LICENSE_GRACE_PERIOD;
+}
+
+export function displayExpiryDate() {
+    return (
+        <FormattedDate
+            value={new Date(parseInt(global.window.mm_license.ExpiresAt, 10))}
+            day='2-digit'
+            month='long'
+            year='numeric'
+        />
+    );
+}