Login: automatically log out on expired token.

This is a bit of a workaround.
The problem is that we cache auth tokens, but that auth tokens can expire.
Thins means that we could have a stale auth token after coming back to
the app after a long time, so we need to fetch a new one.

Logging out is a bit of a nuclear option, but since this is a rare
scenario, it can do for now.

src/LoginGate.tsx

@@ -12,7 +12,7 @@ import LoginForm from './components/LoginForm';
 import EncryptionLoginForm from './components/EncryptionLoginForm';
 
 import { store, StoreState, CredentialsDataRemote } from './store';
-import { deriveKey, fetchCredentials, fetchUserInfo } from './store/actions';
+import { deriveKey, fetchCredentials, fetchUserInfo, logout } from './store/actions';
 
 import * as EteSync from 'etesync';
 import * as C from './constants';
@@ -35,9 +35,15 @@ function EncryptionPart(props: { credentials: CredentialsDataRemote }) {
       setUserInfo(fetchedUserInfo.payload);
     }).catch((e: Error) => {
       // Do nothing.
-      if ((e instanceof EteSync.HTTPError) && (e.status !== 404)) {
+      if (e instanceof EteSync.HTTPError) {
+        if (e.status === 404) {
+          // Do nothing
+        } else if (e.status === 401) {
+          store.dispatch(logout(credentials));
+        } else {
           setError(e);
         }
+      }
     }).finally(() => {
       setFetched(true);
     });

src/store/actions.ts

@@ -6,7 +6,7 @@ import { Action, createAction, createActions } from 'redux-actions';
 import * as EteSync from 'etesync';
 import { UserInfo } from 'etesync';
 
-import { CredentialsData, EntriesData, SettingsType } from './';
+import { CredentialsData, CredentialsDataRemote, EntriesData, SettingsType } from './';
 
 export const { fetchCredentials } = createActions({
   FETCH_CREDENTIALS: (username: string, password: string, server: string) => {
@@ -34,7 +34,7 @@ export const { fetchCredentials } = createActions({
 
 export const logout = createAction(
   'LOGOUT',
-  (etesync: CredentialsData) => {
+  (etesync: CredentialsDataRemote) => {
     (async () => {
       const authenticator = new EteSync.Authenticator(etesync.serviceApiUrl);
       try {