Load mermaid.min.js conditionally?

[mgaitan]

Load mermaid.min.js conditionally?

[hugovk]

Edit: the first version here didn't work in all cases, here's a better method from kedro-org/kedro#1392:

Add this to conf.py:

# conf.py
from sphinxcontrib.mermaid import mermaid

MERMAID_JS_URL = "https://unpkg.com/mermaid/dist/mermaid.min.js"
mermaid_version = ""  # We add a minified Mermaid script file ourselves


def remove_unused_mermaid_script_file(app, pagename, templatename, context, doctree):
    # The `doctree` arg is `None` when not created from a reST document.
    if not doctree:
        return

    # Remove the Mermaid JavaScript from pages without Mermaid diagrams.
    if not doctree.next_node(mermaid):
        # Create a copy of `context["script_files"]`; modifying the list
        # in place affects all pages, because they all use the same ref.
        context["script_files"] = [
            x for x in context["script_files"] if x != MERMAID_JS_URL
        ]

    # Remove "None" entries added when `mermaid_version` is set to `""`.
    context["script_files"] = [x for x in context["script_files"] if x != "None"]


def setup(app):
    app.add_js_file(MERMAID_JS_URL)
    app.connect("html-page-context", remove_unused_mermaid_script_file)