Basic reusable jekyll gallery utilising variable

a-gallery.md

layout	title	permalink	gallery-key
gallery	A Gallery!	/a-gallery/	my-holiday-photos

all images in /assets/gallery/my-holiday-photos/ will show here

gallery.html

---
layout: default
---
# placed in /_layouts/
{% capture gallery_path %}assets/gallery/{{ page.gallery-key }}{% endcapture %}
{% for image in site.static_files %}
    {% if image.path contains gallery_path %}
        <img src="{{ site.baseurl }}{{ image.path }}" alt="image" />
    {% endif %}
{% endfor %}

May I kindly ask how does it work?

Just put those two file into /_layouts/gallery.html and a readme file?

Been a very long time since I've used this or even jekyll but that should basically be it yeah @xihajun

Add the layout in _layouts, then use the layout in front matter as shown in the a-gallery.md example (look at the raw markdown, the gist viewing is formatting the md in a way that is useless for jekyll markdown based pages)

thank you 😊 @joshdavenport