ryland 0.12.0

A simple static site generation library

Ryland

A simple static site generation library

Current Features

• use of Jinja2 templates
• render page-level markdown including frontmatter support
• render markdown within data using filter
• pull data directly from JSON or YAML files within templates
• copy static files and directory trees (for stylesheets, scripts, fonts, images)
• generate hash for cache-busting
• built-in and custom compositional context transformations ("tubes") including ability to calculate some context variables from others

History

I've generally found the framework-approach of most static site generators to either be far too complex for my needs or too restricted to just blogs or similar. Over the years, I've generated many static sites with lightweight, bespoke Python code and hosted them on GitHub pages. I've ended up repeating myself a lot so I'm now cleaning it all up and generalizing my prior work as this library.

Changelog

Now see CHANGELOG.md

Example Usage

pip install ryland (or equivalent).

Then write a build script of the following form:

from ryland import Ryland

ROOT_DIR = Path(__file__).parent.parent
OUTPUT_DIR = ROOT_DIR / "output"
PANTRY_DIR = ROOT_DIR / "pantry"
TEMPLATE_DIR = ROOT_DIR / "templates"

ryland = Ryland(output_dir=OUTPUT_DIR, template_dir=TEMPLATE_DIR)

ryland.clear_output()

## copy and hash static files

ryland.copy_to_output(PANTRY_DIR / "style.css")
ryland.add_hash("style.css")

## render templates

ryland.render_template("404.html", "404.html")
ryland.render_template("about_us.html", "about-us/index.html")

# construct context variables

ryland.render_template("homepage.html", "index.html", {
    # context variables
})

## and/or generate from Markdown files

PAGES_DIR = Path(__file__).parent / "pages"

for page_file in PAGES_DIR.glob("*.md"):
    ryland.render_markdown(page_file, "page.html")

or, for more control, context transformations (or "tubes") can be explicitly composed together:

for page_file in sorted(PAGES_DIR.glob("*.md")):
    ryland.render(
        load(page_file),
        markdown(frontmatter=True),
        excerpt(),
        {"url": f"/{page_file.stem}/"},
        collect_tags(),
        {"template_name": "page.html"},
    )

Also see examples/ in this repo.

Alternative Initialization

If your output directory is ./output/ and your template directory is ./templates/ (relative to the build script), you can just initialize with:

ryland = Ryland(__file__)

Ryland also takes a url_root if the generated site will live somewhere other than directly under /.

The calc_url function (below) can be helpful in constructing urls that honour this.

Cache-Busting Hashes

The add_hash makes it possible to do

<link rel="stylesheet" href="/style.css?{{ HASHES['style.css'] }}">

in the templates to bust the browser cache when a change is made to a stylesheet, script, etc.

Note that calc_url (see below) will automatically add the hash if one exists, so the following is equivalent:

<link rel="stylesheet" href="{{ calc_url('style.css') }}">

Render Markdown Method

ryland.render_markdown takes a Path to a Markdown file and a template name.

The Markdown is rendered to HTML and passed to the template as content. The YAML frontmatter (if it exists) is passed to the template as frontmatter.

Under the covers, this is just a render call with a pre-defined set of tubes (see below) but is handy for just rendering a Markdown file to HTML with Jinja2 templating.

Paginated Method

ryland.paginated takes a list of contexts and added a next and prev to each of them.

For example:

>>> ryland.paginated([{"post": "foo"}, {"post": "bar"}])
[{'post': 'foo', 'prev': None, 'next': {'post': 'bar'}}, {'post': 'bar', 'prev': {'post': 'foo'}, 'next': None}]

or, to give a real-world example:

posts = [
    ryland.process(
        load(post_file),
        markdown(frontmatter=True),
        {"url": f"/{post_file.stem}/"},
        {"template_name": "post.html"},
    )
    for post_file in sorted(POSTS_DIR.glob("*.md"))
]
for post in ryland.paginated(posts, fields=["url", "frontmatter"]):
    ryland.render(post)

ryland.paginated takes an optional fields parameter to project which context variables are included in next and prev.

Markdown Filter

To render a markdown context variable:

{{ content | markdown }}

Calc URL Function

The template function calc_url will honour the url_root and will automatically add the cache-busting hash if one exists.

So if the url_root is /my-site/ and style.css has been hashed, then {{ calc_url('style.css') }} will be expanded to /my-site/style.css?HASH.

If calc_url is given a context (dictionary) rather than a string, the url value will be used. This enables things like

<a href="{{ calc_url(page) }}"> if, for example, page is the context for the page being linked to.

Data Function

You can put together your template context in your Python build script or you can pull data directly from a JSON or YAML file within a template.

Here's an example of the latter:

<div>
  <h2>Latest News</h2>

  {% for news_item in data("news_list.json")[:3] %}
    <div>
      <div class="news-dateline">{{ news_item.dateline }}</div>
      <p>{{ news_item.content }}</p>
    </div>
  {% endfor %}
</div>

Tubes

A "tube" is a function that takes a context dictionary and returns a new one while also being able to access the Ryland instance.

Built-in tube factories in ryland.tubes include the follow:

• load(source_path: Path) loads the given path and puts it on the context as source_path and the contents as source_content.
• markdown(frontmatter=False) converts the Markdown in source_content to HTML and puts it in content. Optionally puts the YAML frontmatter in frontmatter.
• excerpt() extracts the first paragraph of content and puts it in excerpt.
• debug(pretty=True) outputs the context at that point to stderr (by default pretty-printing it).
• project(keys: list[str]) keeps only the listed keys in the context.

Developers can write their own tubes or tube factories, for example here to collect pages by tag:

tags = defaultdict(list)

def collect_tags():
    def tube(ryland: Ryland, context: Dict[str, Any]) -> Dict[str, Any]:
        frontmatter = context["frontmatter"]
        for tag in frontmatter.get("tags", []):
            tags[tag].append(
                ryland.process(
                    context,
                    project(["frontmatter", "url", "excerpt"]),
                )
            )
        return context
    return tube

This builds up a dictionary tags which, for each tag, contains a list of contexts containing the frontmatter, url, and excerpt for each page with that tag in its frontmatter.

Process Method

The ryland.process method takes a series of dictionaries and tubes and builds up a new context.

Render Method

The ryland.render method processes a series of dictionary and tubes and then uses the resultant context to render a template. The template name is given by template_name in the context and the output path is determined by the url in the context.

For example:

for tag in tags:
    ryland.render(
        {
            "tag": tag,
            "pages": tags[tag],
            "url": f"/tag/{tag}/",
            "template_name": "tag.html",
        },
    )

The Get Context Helper

ryland.helpers.get_context allows the retrieval of values from a context using dotted path notation and with defaulting.

For example, in

for page_file in sorted(PAGES_DIR.glob("*.md")):
    ryland.render(
        load(page_file),
        markdown(frontmatter=True),
        excerpt(),
        {"url": get_context("frontmatter.url", f"/{page_file.stem}/")},
        collect_tags(),
        {"template_name": get_context("frontmatter.template_name", "page.html")},
    )

the url and template_name can be overridden in the page's frontmatter.

Sites Currently Using Ryland

• https://projectamaze.com
• https://digitaltolkien.com
• https://jktauber.com
• https://cite.digitaltolkien.com

Other Projects Building on Ryland

• coming soon

Roadmap

In no particular order:

• move over other sites to use Ryland
• incorporate more common elements that emerge
• improve error handling
• produce a Ryland-generated website for Ryland
• document how to automatically build with GitHub actions
• write up a cookbook
• add a command-line tool for starting a Ryland-based site

Because Ryland is a library, a lot of missing features can just be implemented by the site developer. However, if three or more sites duplicate effort in their build script, I'll consider at least adding helper code to Ryland.

Once five independent people are running sites built with Ryland, I will declare 1.0.0.