Architecture

md2pdf converts Markdown to PDF through a four-stage pipeline.

Pipeline overview

1. Parse — goldmark converts Markdown to HTML with GFM extensions (tables, fenced code blocks, strikethrough). Mermaid code blocks are extracted and replaced with placeholders.
2. Render diagrams — each Mermaid block is rendered to SVG via the mmdc CLI.
3. Build HTML — a self-contained HTML file is assembled with GitHub-flavored CSS, @font-face declarations for Noto Sans CJK JP, and the rendered SVGs injected inline.
4. Print PDF — a headless Chromium browser (via Playwright) loads the HTML and prints it to PDF.

Source layout

internal/converter/
  converter.go   # Orchestrates the pipeline, manages temp directory
  parser.go      # Stage 1 — goldmark parsing
  mermaid.go     # Stage 2 — mmdc SVG rendering
  html.go        # Stage 3 — HTML assembly
  pdf.go         # Stage 4 — Chromium PDF printing

cmd/md2pdf/
  main.go        # CLI entry point
  flags.go       # Argument parsing, auto-detection

External dependencies