rework the navigation menu of the Web UI

CHANGES.md

@@ -23,7 +23,11 @@
 * Move the host statistics collector to the statistics collector process. 
   The option `stats_collecting_period` is now applicable to host statistics collector.
 
-* Re-apply the eventual process `extra_args` when restarting the application.  
+* Re-apply the eventual process `extra_args` when restarting the application.
+
+* In the Supervisors navigation menu of the Web UI, add a red light to Supervisor instances having raised a failure.
+
+* Rework the navigation menu of the Web UI.
 
 * Rework **Supvisors** `RPCInterface` exceptions.
 
@@ -534,7 +538,7 @@
 * In the Process page of the Web UI, expand / shrink actions are not applicable to programs that are not owned
   by a Supervisor group.
 
-* In the application navigation menu of the Web UI, add a red light near the Applications title if any application
+* In the Applications navigation menu of the Web UI, add a red light near the Applications title if any application
   has raised a failure.
 
 * In the Application page of the Web UI, default starting strategy is the starting strategy defined
@@ -566,7 +570,7 @@
 
 * Enable stop sequence on *Unmanaged* applications.
 
-* In the application navigation menu of the Web UI, add a red light to applications having raised a failure.
+* In the Applications navigation menu of the Web UI, add a red light to applications having raised a failure.
 
 * New application rules `distributed` and `addresses` added to the **Supvisors** rules file.
   Non-distributed applications have all their processes started on the same node chosen in accordance with the

supvisors/ui/application.html

@@ -24,7 +24,7 @@ <h1><a href="index.html" meld:id="supvisors_mid"><img src="img/supvisors.png"/><
             </header>
 
             <nav id="instance_list">
-                <h2>Supervisors</h2>
+                <h2 meld:id="instance_h_mid">Supervisors</h2>
                 <div>
                     <ul>
                         <li meld:id="instance_li_mid"><a href="#" meld:id="instance_a_mid">Supervisor</a></li>

supvisors/ui/css/menu.css

@@ -111,5 +111,6 @@ nav li.failure::after {
     content: url(../img/red_light_30.png);
     float: right;
     position: relative;
-    top: -30px;
+    top: -29px;
+    right: -5px;
 }

supvisors/ui/host_instance.html

@@ -24,7 +24,7 @@ <h1><a href="index.html" meld:id="supvisors_mid"><img src="img/supvisors.png"/><
             </header>
 
             <nav id="instance_list">
-                <h2>Supervisors</h2>
+                <h2 meld:id="instance_h_mid">Supervisors</h2>
                 <div>
                     <ul>
                         <li meld:id="instance_li_mid"><a href="#" meld:id="instance_a_mid">Supervisor</a></li>

supvisors/ui/index.html

@@ -27,7 +27,7 @@ <h1>
             </header>
 
             <nav id="instance_list">
-                <h2>Supervisors</h2>
+                <h2 meld:id="instance_h_mid">Supervisors</h2>
                 <div>
                     <ul>
                         <li meld:id="instance_li_mid"><a href="#" meld:id="instance_a_mid">Supervisor</a></li>

supvisors/ui/proc_instance.html

@@ -24,7 +24,7 @@ <h1><a href="index.html" meld:id="supvisors_mid"><img src="img/supvisors.png"/><
             </header>
 
             <nav id="instance_list">
-                <h2>Supervisors</h2>
+                <h2 meld:id="instance_h_mid">Supervisors</h2>
                 <div>
                     <ul>
                         <li meld:id="instance_li_mid"><a href="#" meld:id="instance_a_mid">Supervisor</a></li>

supvisors/web/viewhandler.py

@@ -131,10 +131,11 @@ def write_nav(self, root, identifier=None, appli=None):
         self.write_nav_instances(root, identifier)
         self.write_nav_applications(root, appli)
 
-    def write_nav_instances(self, root, identifier):
+    def write_nav_instances(self, root, identifier: str) -> None:
         """ Write the node part of the navigation menu. """
         mid_elt = root.findmeld('instance_li_mid')
         identifiers = list(self.supvisors.mapper.instances.keys())
+        any_failure = False
         # in discovery mode, other Supvisors instances arrive randomly in every Supvisors instance
         # so let's sort them by name
         if self.supvisors.options.discovery_mode:
@@ -145,10 +146,14 @@ def write_nav_instances(self, root, identifier):
             except KeyError:
                 self.logger.debug(f'ViewHandler.write_nav_instances: failed to get instance status from {item}')
             else:
+                failure = status.has_error()
+                any_failure |= failure
                 # set element class
                 update_attrib(li_elt, 'class', status.state.name)
                 if item == identifier:
                     update_attrib(li_elt, 'class', 'active')
+                if failure:
+                    update_attrib(li_elt, 'class', 'failure')
                 # set hyperlink attributes
                 elt = li_elt.findmeld('instance_a_mid')
                 if status.state_modes.starting_jobs or status.state_modes.stopping_jobs:
@@ -161,10 +166,14 @@ def write_nav_instances(self, root, identifier):
                 else:
                     update_attrib(elt, 'class', 'off')
                 # set content
-                identifier = item
+                displayed_item = item
                 if item == self.sup_ctx.master_identifier:
-                    identifier = f'{MASTER_SYMBOL} {item}'
-                elt.content(identifier)
+                    displayed_item = f'{MASTER_SYMBOL} {item}'
+                elt.content(displayed_item)
+        # warn at title level if any application has a failure
+        if any_failure:
+            elt = root.findmeld('instance_h_mid')
+            update_attrib(elt, 'class', 'failure')
 
     def write_nav_applications(self, root, appli):
         """ Write the application part of the navigation menu. """
@@ -199,7 +208,8 @@ def write_nav_applications(self, root, appli):
             elt.content(item.application_name)
         # warn at title level if any application has a failure
         if any_failure:
-            update_attrib(root.findmeld('appli_h_mid'), 'class', 'failure')
+            elt = root.findmeld('appli_h_mid')
+            update_attrib(elt, 'class', 'failure')
 
     def write_header(self, root):
         """ Write the header part of the page.