validate-html2

A GitHub Action that validates an HTML file against the HTML 2.0 DTD (RFC 1866, 1995) — real SGML validation with OpenSP's onsgmls, using the DTD, SGML declaration, and Latin-1 entity set vendored from w3.org.

Usage

steps:
  - uses: actions/checkout@v4
  - uses: lra/validate-html2@v1
    with:
      file: index.html

Inputs

Input	Required	Description
file	yes	Path to the HTML file to validate
strip	no	grep -E pattern; matching lines are removed before validation. Useful to allow a deliberate anachronism, e.g. an analytics <script> tag.

  - uses: lra/validate-html2@v1
    with:
      file: index.html
      strip: _vercel/insights

The action fails if the file is not valid HTML 2.0, with onsgmls errors in the log. Linux runners only.