Add api.group.read to get a group by id

src/sidebar/services/api.js

@@ -232,6 +232,7 @@ function api(apiRoutes, auth, store) {
       member: {
         delete: apiCall('group.member.delete'),
       },
+      read: apiCall('group.read'),
     },
     groups: {
       list: apiCall('groups.read'),

src/sidebar/services/test/api-index.json

@@ -29,6 +29,11 @@
           "method": "DELETE",
           "desc": "Remove the current user from a group."
         }
+      },
+      "read": {
+        "url": "https://example.com/api/groups/:id",
+        "method": "GET",
+        "desc": "Fetch a group."
       }
     },
     "links": {

src/sidebar/services/test/api-test.js

@@ -124,6 +124,14 @@ describe('sidebar.services.api', function() {
     return api.group.member.delete({ pubid: 'an-id', userid: 'me' });
   });
 
+  it('gets a group by provided group id', () => {
+    const group = { id: 'group-id', name: 'Group' };
+    expectCall('get', 'groups/group-id', 200, group);
+    return api.group.read({ id: 'group-id' }).then(group_ => {
+      assert.deepEqual(group_, group);
+    });
+  });
+
   it('removes internal properties before sending data to the server', () => {
     const annotation = {
       $highlight: true,