Add prev/next buttons when viewing upgrade details

tailbone/templates/master/view.mako

@@ -26,6 +26,24 @@
   % endif
 </%def>
 
+<%def name="content_title()">
+  % if master.supports_prev_next:
+      <div style="float: right;">
+        % if prev_instance:
+            ${h.link_to(u"« Older", url('{}.view'.format(route_prefix), uuid=prev_instance.uuid), class_='button')}
+        % else:
+            ${h.link_to(u"« Older", '#', class_='button', disabled='disabled')}
+        % endif
+        % if next_instance:
+            ${h.link_to(u"Newer »", url('{}.view'.format(route_prefix), uuid=next_instance.uuid), class_='button')}
+        % else:
+            ${h.link_to(u"Newer »", '#', class_='button', disabled='disabled')}
+        % endif
+      </div>
+  % endif
+  <h1>${instance_title}</h1>
+</%def>
+
 <%def name="context_menu_items()">
   <li>${h.link_to("Permalink for this {}".format(model_title), action_url('view', instance))}</li>
   % if master.has_versions and request.rattail_config.versioning_enabled() and request.has_perm('{}.versions'.format(permission_prefix)):

tailbone/templates/themes/better/master/view.mako

@@ -1,8 +1,6 @@
 ## -*- coding: utf-8; -*-
 <%inherit file="tailbone:templates/master/view.mako" />
 
-<%def name="content_title()">
-  <h1>${instance_title}</h1>
-</%def>
+## TODO: remove this once it's safe (no callers use it)...
 
 ${parent.body()}

tailbone/views/master.py

@@ -75,6 +75,7 @@ class MasterView(View):
     executable = False
     execute_progress_template = None
     execute_progress_initial_msg = None
+    supports_prev_next = False
 
     supports_mobile = False
     mobile_creatable = False

tailbone/views/upgrades.py

@@ -56,6 +56,7 @@ class UpgradeView(MasterView):
     executable = True
     execute_progress_template = '/upgrade.mako'
     execute_progress_initial_msg = "Upgrading"
+    supports_prev_next = True
 
     labels = {
         'executed_by': "Executed by",
@@ -127,6 +128,18 @@ class UpgradeView(MasterView):
         if upgrade.status_code == self.enum.UPGRADE_STATUS_EXECUTING:
             return 'notice'
 
+    def template_kwargs_view(self, **kwargs):
+        upgrade = kwargs['instance']
+        upgrades = self.Session.query(model.Upgrade)\
+                               .filter(model.Upgrade.uuid != upgrade.uuid)
+        kwargs['prev_instance'] = upgrades.filter(model.Upgrade.created <= upgrade.created)\
+                                          .order_by(model.Upgrade.created.desc())\
+                                          .first()
+        kwargs['next_instance'] = upgrades.filter(model.Upgrade.created >= upgrade.created)\
+                                          .order_by(model.Upgrade.created)\
+                                          .first()
+        return kwargs
+
     def configure_form(self, f):
         super(UpgradeView, self).configure_form(f)
         f.set_enum('status_code', self.enum.UPGRADE_STATUS)