[Camden] Refactor generic error template.

templates/web/base/errors/generic.html

@@ -1,18 +1,25 @@
+[% IF message == 'invalid id_token' ~%]
+[% title = BLOCK %][% TRY %][% PROCESS 'errors/_sso_title.html' %][% CATCH file %]Login[% END %][% END ~%]
+[% END %]
 [% DEFAULT title = loc('Error') %]
 [% DEFAULT header_class = 'failure' %]
-[% INCLUDE 'header.html', title = title %]
+[% INCLUDE 'header.html' %]
 
 [% IF csrf_token ~%]
 <input type="hidden" name="token" value="[% csrf_token %]">
 [% END ~%]
 
-<div class="confirmation-header confirmation-header--[% header_class %]">
-    <h1>[% title %]</h1>
-    <p>[% message | safe %]</p>
-    [% IF error_id %]
-        <small>[% tprintf(loc('Code: %s'), error_id) %]</small>
-    [% END %]
-</div>
+[% IF message == 'invalid id_token' %]
+    [% PROCESS 'errors/sso.html' %]
+[% ELSE %]
+    <div class="confirmation-header confirmation-header--[% header_class %]">
+        <h1>[% title %]</h1>
+        <p>[% message | safe %]</p>
+        [% IF error_id %]
+            <small>[% tprintf(loc('Code: %s'), error_id) %]</small>
+        [% END %]
+    </div>
+[% END %]
 
 [% INCLUDE 'footer.html' %]
 

templates/web/base/errors/sso.html

@@ -0,0 +1,21 @@
+[%
+# Very occasionally the user will run into this error when logging in, either because
+# the redirects from B2C aren't working correctly, or the user's browser doesn't have
+# a cookie set, or their session doesn't have the relevant oauth values stored.
+# The exact cause is currently unknown and hard to pin down due to the transient
+# nature of the bug.
+# Because the login invariably works the next time the user tries, this workaround
+# just presents the OIDC login button again (labelled as a 'continue' button...) and
+# will thus allow them to login successfully. In theory.
+%]
+<div>
+    <h1>[% title %]</h1>
+    <form action="/auth" method="post" name="general_auth" class="validate">
+        <input type="hidden" name="r" value="[% c.req.params.r | html %]">
+        <div class="form-box">
+            <button name="social_sign_in" value="oidc" class="btn btn--block btn--social btn--oidc">
+                Click here to continue...
+            </button>
+            </div>
+    </form>
+</div>

templates/web/brent/errors/_sso_title.html

@@ -0,0 +1 @@
+My Account login

templates/web/camden/errors/_sso_title.html

@@ -0,0 +1 @@
+Staff login

templates/web/highwaysengland/errors/_sso_title.html

@@ -0,0 +1 @@
+Staff login

templates/web/tfl/errors/_sso_title.html

@@ -0,0 +1 @@
+Staff login