Add Glucose Monitor Widget

[metamorph-dev]

This change will add a Glucose Monitor Widget which you can connect to the Nightscout CGM remote monitor

This widget allows you to see your or your nearest and dearest blood sugar level in real time

[Video-Nomad]

Thanks for the pull request! Really cool widget idea. I don't think we can test it though, so I guess we will have to trust you that it works 😅

However, there's one slight problem - requests library. We explicitly removed it from YASB because it affected the startup time too much. It's a huge library to include just to get a request going. Please consider rewriting that part to urllib if possible.

[Video-Nomad]

Added some comments.

[Video-Nomad]

Setting secret in the config is not a great idea. Using env var should be an option, similar to how weather widget or github widget handles these.

[Video-Nomad]

Although using templates is definitely a valid approach, we are currently switching to format and format_map instead. So, the placeholders should be in the format {sgv} {direction} etc.

Check the #498 for similar approach. I don't know if that PR will be merged or not, but we are using curly braces in all the widget so this should be consistent.

[metamorph-dev]

Now it supports environment variables and uses format_map.

I added secret_env_name in the configuration, 'cause it might not be a single widget of this type.

[amnweb]

YASB can read environment variables directly, like secret_env_name: "$env:SECRET", or from the .env file, so that’s no problem at all.
But I don’t understand this widget host: "https://your-domain.com". What exactly is host? I mean, it’s not clearly documented how to use this widget.

[metamorph-dev]

Added a description for the widget in the wiki with the links for the Nightscout official documentation.

[metamorph-dev]

I can give you my config for this widget with all the credentials so you can see how it looks.

After that of course I'll revoke my API keys.

[amnweb]

Added a description for the widget in the wiki with the links for the Nightscout official documentation.

OK, now it’s easier for me to understand what this widget is actually for. Thanks for the info!
I have a few more suggestions to keep the codebase clean: the data label/placeholder should be label: {sgv}{direction} instead of $sgv$direction.

You should remove the container_padding.

        self._widget_container_layout.setContentsMargins(
            self._padding["left"],
            self._padding["top"],
            self._padding["right"],
            self._padding["bottom"],
        )

It’s deprecated, and we’ll remove it from all widgets in the future, so there’s no need to create new widgets with this option, the style is available via CSS.
Also all widgets support shadow so you can add it using add_shadow.

And lastly, it’s better to keep icons as Unicode UTF-16 characters rather than as image icons.

[Video-Nomad]

Looks good to me. There's no explicit icon/label separation as we have on other text-based widgets, but I don't know how important it is for this widget. This part as an example:

yasb/src/core/widgets/yasb/custom.py

Lines 137 to 168 in 0919bbb

	def _create_dynamically_label(self, content: str, content_alt: str):
	def process_content(content, is_alt=False):
	label_parts = re.split("(<span.*?>.*?</span>)", content)
	widgets = []
	for part in label_parts:
	part = part.strip()
	if not part:
	continue
	if "<span" in part and "</span>" in part:
	class_name = re.search(r'class=(["\'])([^"\']+?)\1', part)
	class_result = class_name.group(2) if class_name else "icon"
	icon = re.sub(r"<span.*?>|</span>", "", part).strip()
	label = QLabel(icon)
	label.setProperty("class", class_result)
	else:
	label = QLabel(part)
	label.setProperty("class", "label alt" if is_alt else "label")
	label.setText(self._label_placeholder)
	label.setAlignment(Qt.AlignmentFlag.AlignCenter)
	self._set_cursor(label)
	add_shadow(label, self._label_shadow)
	self._widget_container_layout.addWidget(label)
	widgets.append(label)
	if is_alt:
	label.hide()
	else:
	label.show()
	return widgets
	self._widgets = process_content(content)
	self._widgets_alt = process_content(content_alt, is_alt=True)

Other than that, I see no issues at least on the surface.

[metamorph-dev]

• Rebased on the main branch
• Added explicit icon/label separation
• Added notification on error

[metamorph-dev]

Is everything OK?
Do I need to add something more?

[Video-Nomad]

Added some comments

[metamorph-dev]

Exactly

[Video-Nomad]

Missing add_shadow configuration

[metamorph-dev]

Exactly

[metamorph-dev]

• Added special setting notify_on_error to make notifications optional
• Added explicit zeroed contents margin
• Added .cgm-widget .icon style in CSS example documentation
• Added <span> for icons in all places
• Added label_shadow and container_shadow configuration
• Added error label

[metamorph-dev]

Added blood sugar level (sgv) css styling support for the label.

Now using <span class="sgv">{sgv}</span> in the label, in-range/out-range CSS styles, and sgv_range configuration, it is available to set preferred CSS styles based on whether the blood sugar level is in range or not.

For example: display a good blood sugar level with green color or with red color if it is bad.

[Video-Nomad]

@metamorph-dev Can you attach a dummy response example? Just json. Remove all the personal or sensitive data, of course. Just to test how this widget would look like when the server is working as expected.

[metamorph-dev]

@metamorph-dev Can you attach a dummy response example? Just json. Remove all the personal or sensitive data, of course. Just to test how this widget would look like when the server is working as expected.

[
  {
    "_id": "6900db08b2b258d49270ca37",
    "device": "xDrip-LibreReceiver",
    "date": 1761663707057,
    "dateString": "2025-10-28T15:01:47.057Z",
    "sgv": 147,
    "delta": -2.997,
    "direction": "Flat",
    "type": "sgv",
    "filtered": 142000,
    "unfiltered": 142000,
    "rssi": 100,
    "noise": 1,
    "sysTime": "2025-10-28T15:01:47.057Z",
    "utcOffset": 60,
    "mills": 1761663707057
  }
]

The API stores sgv in mg/dl

[Video-Nomad]

Looks good to me! Up to @amnweb to merge this of course. Thanks for the tweaks @metamorph-dev 👍

[amnweb]

Looks good to me as well, but since this PR will directly change the README, I won’t merge it until we’re ready to build the stable release. @metamorph-dev if you still need to change something, please let me know.