Fixes: Connecting slack commands from subdomain

app/scenes/Settings/Slack.js

@@ -11,12 +11,14 @@ import HelpText from 'components/HelpText';
 import SlackButton from './components/SlackButton';
 import CollectionsStore from 'stores/CollectionsStore';
 import IntegrationsStore from 'stores/IntegrationsStore';
+import AuthStore from 'stores/AuthStore';
 import Notice from 'shared/components/Notice';
 import getQueryVariable from 'shared/utils/getQueryVariable';
 
 type Props = {
   collections: CollectionsStore,
   integrations: IntegrationsStore,
+  auth: AuthStore,
 };
 
 @observer
@@ -36,7 +38,8 @@ class Slack extends React.Component<Props> {
   }
 
   render() {
-    const { collections, integrations } = this.props;
+    const { collections, integrations, auth } = this.props;
+    const teamId = auth.team ? auth.team.id : '';
 
     return (
       <CenteredContent>
@@ -48,6 +51,12 @@ class Slack extends React.Component<Props> {
             Outline to your team. Try again?
           </Notice>
         )}
+        {this.error === 'unauthenticated' && (
+          <Notice>
+            Something went wrong while authenticating your request. Please try
+            logging in again?
+          </Notice>
+        )}
         <HelpText>
           Preview Outline links your team mates share and use the{' '}
           <Code>/outline</Code> slash command in Slack to search for documents
@@ -60,7 +69,7 @@ class Slack extends React.Component<Props> {
             <SlackButton
               scopes={['commands', 'links:read', 'links:write']}
               redirectUri={`${BASE_URL}/auth/slack.commands`}
-              state=""
+              state={teamId}
             />
           )}
         </p>
@@ -130,4 +139,4 @@ const Code = styled.code`
   border-radius: 4px;
 `;
 
-export default inject('collections', 'integrations')(Slack);
+export default inject('collections', 'integrations', 'auth')(Slack);

server/auth/slack.js

@@ -69,8 +69,9 @@ router.get('slack.callback', auth({ required: false }), async ctx => {
   ctx.signIn(user, team, 'slack', isFirstSignin);
 });
 
-router.get('slack.commands', auth(), async ctx => {
-  const { code, error } = ctx.request.query;
+router.get('slack.commands', auth({ required: false }), async ctx => {
+  const { code, state, error } = ctx.request.query;
+  const user = ctx.state.user;
   ctx.assertPresent(code || error, 'code is required');
 
   if (error) {
@@ -78,9 +79,28 @@ router.get('slack.commands', auth(), async ctx => {
     return;
   }
 
+  // this code block accounts for the root domain being unable to
+  // access authentcation for subdomains. We must forward to the appropriate
+  // subdomain to complete the oauth flow
+  if (!user) {
+    if (state) {
+      try {
+        const team = await Team.findById(state);
+        return ctx.redirect(
+          `${team.url}/auth${ctx.request.path}?${ctx.request.querystring}`
+        );
+      } catch (err) {
+        return ctx.redirect(
+          `/settings/integrations/slack?error=unauthenticated`
+        );
+      }
+    } else {
+      return ctx.redirect(`/settings/integrations/slack?error=unauthenticated`);
+    }
+  }
+
   const endpoint = `${process.env.URL || ''}/auth/slack.commands`;
   const data = await Slack.oauthAccess(code, endpoint);
-  const user = ctx.state.user;
 
   const authentication = await Authentication.create({
     service: 'slack',