Highlight selected page

example/ui_showcase.py

@@ -149,11 +149,17 @@ async def do_magic(_v, _o) -> None:
 
 #############################################################################################
 # Overview page                                                                             #
-# Here we show the ImageMap and HideRows                                                    #
+# Here we show the ImageMap, HideRows, WebPages and submenus.                               #
 #############################################################################################
 
 overview_page = web_server.page('overview', "Overview", menu_entry='Some Submenu', menu_icon='tachometer alternate',
-                                menu_sub_label="Overview")
+                                menu_sub_label="Overview", menu_sub_icon='tachometer alternate')
+
+submenu_page2 = web_server.page('empty-page', "Nothing here", menu_entry='Some Submenu', menu_sub_icon='couch',
+                                menu_sub_label="Empty Submenu")
+
+# adding sub menu entry to `Some Submenu` pointing the page above
+web_server.add_menu_entry('empty-page', label="Some Submenu", sub_icon='motorcycle', sub_label="Empty Submenu 2")
 
 # ImageMap supports all the different Buttons as items, as well as the special ImageMapLabel
 # The optional fourth entry of each item is a list of WebPageItems (everything we have shown so far – even an ImageMap))

shc/web/interface.py

@@ -17,6 +17,7 @@
 import os
 import pathlib
 import weakref
+from dataclasses import dataclass, field
 from json import JSONDecodeError
 from typing import Dict, Iterable, Union, List, Set, Any, Optional, Tuple, Generic, Type, Callable
 
@@ -42,6 +43,26 @@
 LastWillT = Tuple["WebApiObject[T]", T]
 
 
+@dataclass
+class MenuEntrySpec:
+    """Specification of one menu entry within the :class:`WebServer`"""
+    # The name of the page (link target)
+    page_name: Optional[str] = None
+    # The label of the entry in the main menu
+    label: Optional[str] = None
+    # If given, the menu entry is prepended with the named icon
+    icon: Optional[str] = None
+    # Flag whether this menu item is active
+    is_active: bool = False
+
+
+@dataclass
+class SubMenuEntrySpec(MenuEntrySpec):
+    """Specification of a sub menu entry within the :class:`WebServer`"""
+    # List of submenus if any
+    submenus: List[MenuEntrySpec] = field(default_factory=list)
+
+
 class WebServer(AbstractInterface):
     """
     A SHC interface to provide the web user interface and a REST+websocket API for interacting with Connectable objects.
@@ -81,14 +102,14 @@ def __init__(self, host: str, port: int, index_name: Optional[str] = None, root_
         self._associated_tasks: weakref.WeakSet[asyncio.Task] = weakref.WeakSet()
         # last will (object, value) per API websocket client (if set)
         self._api_ws_last_will: Dict[aiohttp.web.WebSocketResponse, LastWillT] = {}
-        # data structure of the user interface's main menu
+        # using class `MenuEntrySpec` and `SubMenuEntrySpec` as data structure for the user interface's main menu
         # The structure looks as follows:
-        # [('Label', 'icon', 'page_name'),
-        #  ('Submenu label', None, [
-        #     ('Label 2', 'icon', 'page_name2'), ...
+        # [('Label', 'icon', 'page_name', 'is_active'),
+        #  ('Submenu label', 'icon', None, 'is_active' [
+        #     ('Label 2', 'icon', 'page_name2', 'is_active'), ...
         #   ]),
         #  ...]
-        self.ui_menu_entries: List[Tuple[str, Optional[str], Union[str, List[Tuple[str, Optional[str], str]]]]] = []
+        self.ui_menu_entries: List[MenuEntrySpec] = []
         # List of all static js URLs to be included in the user interface pages
         self._js_files = [
             "/static/pack/main.js",
@@ -164,6 +185,9 @@ def page(self, name: str, title: Optional[str] = None, menu_entry: Union[bool, s
         Create a new WebPage with a given name.
 
         If there is already a page with that name existing, it will be returned.
+        For convenience you may create a menu entry pointing to the new page by specifying the
+        `menu_entry` attribute.  See :meth:`add_menu_entry` for creating plain menu entries.
+
 
         :param name: The `name` of the page, which is used in the page's URL to identify it.
         :param title: The title/heading of the page. If not given, the name is used.
@@ -197,6 +221,7 @@ def add_menu_entry(self, page_name: str, label: str, icon: Optional[str] = None,
         Create an entry for a named web UI page in the web UI's main navigation menu.
 
         The existence of the page is not checked, so menu entries can be created before the page has been created.
+        See :meth:`page` for creating pages.
 
         :param page_name: The name of the page (link target)
         :param label: The label of the entry (or the submenu to place the entry in) in the main menu
@@ -207,21 +232,26 @@ def add_menu_entry(self, page_name: str, label: str, icon: Optional[str] = None,
         :raises ValueError: If there is already a menu entry with the same label (or a submenu entry with the same two
             labels)
         """
-        existing_entry = next((e for e in self.ui_menu_entries if e[0] == label), None)
+        existing_entry: Optional[MenuEntrySpec] = next((e for e in self.ui_menu_entries if e.label == label), None)
         if not sub_label:
             if existing_entry:
                 raise ValueError("UI main menu entry with label {} exists already. Contents: {}"
-                                 .format(label, existing_entry[2]))
-            self.ui_menu_entries.append((label, icon, page_name))
+                                 .format(label, existing_entry.page_name))
+            self.ui_menu_entries.append(MenuEntrySpec(label=label, icon=icon, page_name=page_name))
 
         elif existing_entry:
-            if not isinstance(existing_entry[2], list):
+            if not isinstance(existing_entry, SubMenuEntrySpec):
                 raise ValueError("Existing UI main menu entry with label {} is not a submenu but a link to page {}"
-                                 .format(label, existing_entry[2]))
-            existing_entry[2].append((sub_label, sub_icon, page_name))
-
+                                 .format(label, existing_entry.page_name))
+            existing_entry.submenus.append(MenuEntrySpec(label=sub_label, icon=sub_icon, page_name=page_name))
         else:
-            self.ui_menu_entries.append((label, icon, [(sub_label, sub_icon, page_name)]))
+            self.ui_menu_entries.append(
+                SubMenuEntrySpec(
+                    label=label,
+                    icon=icon,
+                    submenus=[MenuEntrySpec(label=sub_label, icon=sub_icon, page_name=page_name)],
+                )
+            )
 
     def api(self, type_: Type, name: str) -> "WebApiObject":
         """
@@ -291,11 +321,34 @@ async def _page_handler(self, request: aiohttp.web.Request) -> aiohttp.web.Respo
 
         html_title = self.title_formatter(page.title)
         template = jinja_env.get_template('page.htm')
-        body = await template.render_async(title=page.title, segments=page.segments, menu=self.ui_menu_entries,
-                                           root_url=self.root_url, js_files=self._js_files, css_files=self._css_files,
-                                           server_token=id(self), html_title=html_title)
+        self._mark_active_menu_items(page.name)
+        body = await template.render_async(
+            title=page.title,
+            segments=page.segments,
+            menu=self.ui_menu_entries,
+            root_url=self.root_url,
+            js_files=self._js_files,
+            css_files=self._css_files,
+            server_token=id(self),
+            html_title=html_title,
+            SubMenuEntrySpec=SubMenuEntrySpec,
+        )
         return aiohttp.web.Response(body=body, content_type="text/html", charset='utf-8')
 
+    def _mark_active_menu_items(self, page_name: str):
+        """Set menu items is_active flag if current page matches page_name/target link."""
+        for item in self.ui_menu_entries:
+            if isinstance(item, SubMenuEntrySpec):
+                item.is_active = False
+                for sub_item in item.submenus:
+                    if page_name == sub_item.page_name:
+                        item.is_active = True
+                        sub_item.is_active = True
+                    else:
+                        sub_item.is_active = False
+            else:
+                item.is_active = page_name == item.page_name
+
     async def _ui_websocket_handler(self, request: aiohttp.web.Request) -> aiohttp.web.WebSocketResponse:
         ws = aiohttp.web.WebSocketResponse()
         await ws.prepare(request)

shc/web/templates/base.htm

@@ -32,21 +32,22 @@
 <body>
     {% if menu %}
         <div class="ui sidebar inverted vertical menu main-menu">
-            {% for label, icon, link in menu %}
-                {% if link is string %}
-                    <a class="item" href="{{ root_url }}/page/{{ link }}/">
-                        {% if icon %}<i class="{{ icon }} icon"></i>{% endif %}
-                        {{ label }}
+            {% for item in menu %}
+                {% if item.submenus is not defined %}
+                    <a class="item{% if item.is_active %} activated{% endif %}" href="{{ root_url }}/page/{{ item.page_name }}/">
+                        {% if item.icon %}<i class="{{ item.icon }} icon"></i>{% endif %}
+                        {{ item.label }}
                     </a>
                 {% else %}
-                    <div class="item">
-                        {% if icon %}<i class="{{ icon }} icon"></i>{% endif %}
-                        <div class="header">{{ label }}</div>
+                    <div class="item{% if item.is_active %} activated{% endif %}">
+                        {% if item.icon %}<i class="{{ item.icon }} icon"></i>{% endif %}
+                        <div class="header">{{ item.label }}</div>
                         <div class="menu">
-                            {% for sub_label, sub_icon, sub_link in link %}
-                                <a class="item" href="{{ root_url }}/page/{{ sub_link }}/">
-                                    {% if sub_icon %}<i class="{{ sub_icon }} icon"></i>{% endif %}
-                                    {{ sub_label }}
+                            {% for sub_item in item.submenus %}
+                                <a class="item{% if sub_item.is_active %} selected{% endif %}"
+                                   href="{{ root_url }}/page/{{ sub_item.page_name }}/">
+                                    {% if sub_item.icon %}<i class="{{ sub_item.icon }} icon"></i>{% endif %}
+                                    {{ sub_item.label }}
                                 </a>
                             {% endfor %}
                         </div>
@@ -59,22 +60,24 @@
         {% if menu %}
             <div class="ui large top inverted fixed menu main-menu">
                 <div class="ui container">
-                    {% for label, icon, link in menu %}
-                        {% if link is string %}
-                            <a class="mobile hidden item" href="{{ root_url }}/page/{{ link }}/">
-                                {% if icon %}<i class="{{ icon }} icon"></i>{% endif %}
-                                {{ label }}
+                    {% for item in menu %}
+                        {% if item.submenus is not defined %}
+                            <a class="mobile hidden item{% if item.is_active %} activated{% endif %}"
+                               href="{{ root_url }}/page/{{ item.page_name }}/">
+                                {% if item.icon %}<i class="{{ item.icon }} icon"></i>{% endif %}
+                                {{ item.label }}
                             </a>
                         {% else %}
-                            <div class="mobile hidden ui dropdown item">
-                                {% if icon %}<i class="{{ icon }} icon"></i>{% endif %}
-                                {{ label }}
+                            <div class="mobile hidden ui dropdown item{% if item.is_active %} activated{% endif %}">
+                                {% if item.icon %}<i class="{{ item.icon }} icon"></i>{% endif %}
+                                {{ item.label }}
                                 <i class="dropdown icon"></i>
                                 <div class="menu">
-                                    {% for sub_label, sub_icon, sub_link in link %}
-                                        <a class="item" href="{{ root_url }}/page/{{ sub_link }}/">
-                                            {% if sub_icon %}<i class="{{ sub_icon }} icon"></i>{% endif %}
-                                            {{ sub_label }}
+                                    {% for sub_item in item.submenus %}
+                                        <a class="item{% if sub_item.is_active %} selected{% endif %}"
+                                           href="{{ root_url }}/page/{{ sub_item.page_name }}/">
+                                            {% if sub_item.icon %}<i class="{{ sub_item.icon }} icon"></i>{% endif %}
+                                            {{ sub_item.label }}
                                         </a>
                                     {% endfor %}
                                 </div>

test/test_web.py

@@ -148,6 +148,55 @@ def test_main_menu(self) -> None:
         self.assertEqual(submenu_entry_href.strip(), "http://localhost:42080/page/another_page/")
         submenu_entry.find_element(By.CSS_SELECTOR, 'i.bars.icon')
 
+    def test_main_menu_selection(self) -> None:
+        """Test that the clicked menu item is selected thus highlighted."""
+        self.server.page('index', menu_entry="Home", menu_icon='home')
+        self.server.page('overview', menu_entry="Foo", menu_icon='info')
+
+        # add some pages accessible via submenus
+        self.server.page('submenu1', "Sub1", menu_entry='Some Submenu', menu_icon='bell',
+                         menu_sub_label="Overview")
+        self.server.page('submenu2', "Sub2", menu_entry='Some Submenu',
+                         menu_sub_label="Empty Submenu")
+        self.server.page('submenu3', "Sub3", menu_entry='Some Submenu',
+                         menu_sub_label="Empty Submenu 2")
+
+        self.server_runner.start()
+        self.driver.get("http://localhost:42080")
+
+        # test on startup only 1st item is selected
+        container = self.driver.find_element(By.CSS_SELECTOR, '.pusher')
+        selected_menus = container.find_elements(By.CLASS_NAME, 'activated')
+        self.assertEqual(len(selected_menus), 1)
+        self.assertIn("Home", selected_menus[0].text)
+
+        # test after click on foo only the clicked item is selected
+        foo_link = container.find_element(By.CSS_SELECTOR, 'i.info.icon').find_element(By.XPATH, '..')
+        foo_link.click()
+
+        container = self.driver.find_element(By.CSS_SELECTOR, '.pusher')
+        selected_menus = container.find_elements(By.CLASS_NAME, 'activated')
+        self.assertEqual(len(selected_menus), 1)
+        self.assertIn("Foo", selected_menus[0].text)
+
+        # click top level submenu item 1st to open submenu
+        submenu = container.find_element(By.CSS_SELECTOR, 'i.bell.icon').find_element(By.XPATH, '..')
+        submenu.click()
+
+        # now select submenu item
+        submenu_entry = submenu.find_element(By.XPATH, './/a[contains(@class, "item")]')
+        submenu_entry.click()
+
+        # test after selecting a submenu both are selected the submenu item and the menu item
+        container = self.driver.find_element(By.CSS_SELECTOR, '.pusher')
+        self.assertEqual(len(selected_menus), 1)
+        selected_menus = container.find_elements(By.CLASS_NAME, 'activated')
+        self.assertIn("Some Submenu", selected_menus[0].text)
+        selected_menus = container.find_elements(By.CLASS_NAME, 'selected')
+        self.assertEqual(len(selected_menus), 1)
+        submenu_href: str = str(selected_menus[0].get_attribute("href"))
+        self.assertTrue(submenu_href.endswith("/page/submenu1/"))
+
 
 class MonitoringTest(unittest.TestCase):
     def setUp(self) -> None:

web_ui_src/main.css

@@ -22,6 +22,9 @@ body.pushable>.pusher, body:not(.pushable) {
     line-height: 36px;
 }
 
+.item.activated {
+    background: url("prism.png") !important;
+}
 
 /* ************************** *
  * Semantic UI extensions     *