Show the nomad agent version of the agent the UI is served from

ui/app/services/system.js

@@ -28,6 +28,20 @@ export default class SystemService extends Service {
     });
   }
 
+  @computed
+  get agent() {
+    const token = this.token;
+    return PromiseObject.create({
+      promise: token
+        .authorizedRawRequest(`/${namespace}/agent/self`)
+        .then(jsonWithDefault({}))
+        .then(agent => {
+          agent.version = agent.member?.Tags?.build || 'Unknown';
+          return agent;
+        }),
+    });
+  }
+
   @computed
   get defaultRegion() {
     const token = this.token;

ui/app/styles/components/gutter.scss

@@ -1,4 +1,6 @@
 .gutter {
+  display: flex;
+  flex-direction: column;
   height: 100%;
   border-right: 1px solid $grey-blue;
   overflow: hidden;
@@ -56,6 +58,13 @@
   .menu {
     z-index: $z-gutter;
   }
+
+  .gutter-footer {
+    text-align: center;
+    border-top: 1px solid lighten($grey-blue, 10%);
+    padding: 0.5em 0;
+    margin-top: auto;
+  }
 }
 
 // Treated as an element of the gutter component despite not being nested within

ui/app/templates/components/gutter-menu.hbs

@@ -84,6 +84,9 @@
         <li><LinkTo @route="topology" @activeClass="is-active" data-test-gutter-link="topology">Topology</LinkTo></li>
       </ul>
     </aside>
+    <footer class="gutter-footer">
+      <span class="is-faded">v{{this.system.agent.version}}</span>
+    </footer>
   </div>
 </div>
 <div data-test-page-content class="page-column is-right">

ui/mirage/config.js

@@ -323,6 +323,12 @@ export default function() {
     };
   });
 
+  this.get('/agent/self', function({ agents }) {
+    return {
+      member: this.serialize(agents.first()),
+    };
+  });
+
   this.get('/agent/monitor', function({ agents, nodes }, { queryParams }) {
     const serverId = queryParams.server_id;
     const clientId = queryParams.client_id;

ui/tests/acceptance/regions-test.js

@@ -152,7 +152,7 @@ module('Acceptance | regions (many)', function(hooks) {
     );
   });
 
-  test('when the region is not the default region, all api requests include the region query param', async function(assert) {
+  test('when the region is not the default region, all api requests other than the agent/self request include the region query param', async function(assert) {
     window.localStorage.removeItem('nomadTokenSecret');
     const region = server.db.regions[1].id;
 
@@ -178,7 +178,11 @@ module('Acceptance | regions (many)', function(hooks) {
     );
 
     appRequests.forEach(req => {
-      assert.ok(req.url.includes(`region=${region}`), req.url);
+      if (req.url === '/v1/agent/self') {
+        assert.notOk(req.url.includes('region='), `(no region) ${req.url}`);
+      } else {
+        assert.ok(req.url.includes(`region=${region}`), req.url);
+      }
     });
   });
 });