Metadata-Version: 2.4
Name: pdfmd-cli
Version: 3.21.5
Summary: One command from Markdown to a good-looking PDF: a Pandoc wrapper with smart defaults, project-file discovery and a multi-engine fallback chain
Author: Ali Perdekhan
License-Expression: MIT
Project-URL: Homepage, https://github.com/aliperdehan/pdfmd
Project-URL: Changelog, https://github.com/aliperdehan/pdfmd/blob/main/CHANGELOG.md
Keywords: pandoc,markdown,pdf,latex,cli
Classifier: Environment :: Console
Classifier: Programming Language :: Python :: 3
Classifier: Topic :: Text Processing :: Markup :: Markdown
Classifier: Topic :: Text Processing :: Markup :: LaTeX
Requires-Python: >=3.10
Description-Content-Type: text/markdown
License-File: LICENSE
License-File: pdfmd_inkmd/LICENSE
License-File: pdfmd_inkmd/assets/fonts/DejaVuSans-LICENSE.txt
Requires-Dist: pyyaml
Requires-Dist: pypdf
Provides-Extra: math
Requires-Dist: pymd2pdf<0.7,>=0.6; python_version >= "3.11" and extra == "math"
Requires-Dist: matplotlib; extra == "math"
Provides-Extra: emoji
Requires-Dist: inkmd<0.6,>=0.5; extra == "emoji"
Provides-Extra: pandoc
Requires-Dist: pypandoc_binary; extra == "pandoc"
Dynamic: license-file

# pdfmd

[![Test](https://github.com/aliperdehan/pdfmd/actions/workflows/publish.yml/badge.svg)](https://github.com/aliperdehan/pdfmd/actions/workflows/publish.yml) [![PyPI](https://img.shields.io/pypi/v/pdfmd-cli)](https://pypi.org/project/pdfmd-cli/)

**One command from Markdown to a good-looking PDF.** `pdfmd` wraps
[Pandoc](https://pandoc.org) and fills in everything you would otherwise
have to remember: sensible fonts and margins, the right Markdown dialect,
your project's metadata/preamble/filter files, and a fallback chain across
every PDF engine you have installed.

```console
$ pdfmd lecture
AUTO: READER TITLE MARGIN MONOFONT. Use --verbose to see in full
OK    lecture.md
```

<p align="center">
  <img src="https://raw.githubusercontent.com/aliperdehan/pdfmd/main/docs/lecture.png" width="560" alt="lecture.md rendered to PDF">
</p>

That PDF came from [`examples/lecture.md`](https://github.com/aliperdehan/pdfmd/blob/main/examples/lecture.md), a plain
Markdown file with no front matter and no configuration. Plain `pandoc
lecture.md -o lecture.pdf` doesn't even get that far: its default engine,
`pdflatex`, stops at the `Δ` on line 5 with an error. With a Unicode engine
it would build, but with wide default margins, and with the `# Title`
line as an ordinary section heading instead of a title.

## Why

Pandoc can do nearly anything, but its defaults assume you'll pass the right
flags every time. In practice that means one of two things: a long command
you copy from an old shell history, or a Makefile in every folder. `pdfmd`
turns that knowledge into defaults:

- **It decides per document, not globally.** A file with no YAML front
  matter is treated as ordinary GitHub-flavoured Markdown. A file that has
  front matter is assumed to be written for Pandoc and is left alone.
- **It finds your project files.** A `metadata.yaml`, `preamble.tex` or
  `<name>.lua` beside the document (or in a `metadata/` folder next to it)
  is picked up automatically, so every document in a folder shares one
  house style without any flags.
- **It doesn't give up on the first engine.** If `lualatex` fails or isn't
  installed, it tries the next engine, then the next, and tells you why each
  one failed.
- **It shows what it did.** Every automatic decision prints an `AUTO` line,
  `-v` shows the exact Pandoc command, and every default can be switched off.

## Install

```sh
pipx install pdfmd-cli
```

That puts a `pdfmd` command on your PATH, with its Python dependencies, in
its own isolated environment. `uv tool install pdfmd-cli` does the same.
To update later, run `pipx upgrade pdfmd-cli`. (The package is named
`pdfmd-cli` because `pdfmd` on PyPI is an unrelated PDF-to-Markdown tool.
The command is still `pdfmd`. For the latest unreleased code, use `pipx
install git+https://github.com/aliperdehan/pdfmd`.)

For the full pipeline, `pdfmd` drives programs that pip can't install, so you
also need (without them it still makes a plain PDF; see
[No Pandoc?](#no-pandoc-the-built-in-fallback) below). The quickest way, with no
admin rights, is `pdfmd --install full`, which puts Pandoc and Typst in pdfmd's own
folders; the system installers below do the same job:

- **[Pandoc](https://pandoc.org/installing.html)**
- **at least one PDF engine**. [Typst](https://typst.app) is the quickest
  start; a TeX distribution (MacTeX, TeX Live) gives the best results and
  is what you need for LaTeX packages and math-heavy documents.

```sh
brew install pipx pandoc typst              # macOS, the quick start
brew install --cask mactex-no-gui           # optional: full LaTeX (large)
```

```sh
sudo apt install pipx pandoc texlive-xetex  # Debian/Ubuntu
```

```powershell
py -m pip install --user pipx; py -m pipx ensurepath          # Windows
winget install --id JohnMacFarlane.Pandoc; winget install --id Typst.Typst
```

Every push is tested on Windows, macOS and Linux (Pandoc + Typst: single
files, CSV tables, a book, HTML output); see the
[Test and publish workflow](https://github.com/aliperdehan/pdfmd/actions/workflows/publish.yml).
LaTeX engines aren't part of that automated test on Windows yet.

Optional extras: [Quarto](https://quarto.org) for `.qmd` files,
`pandoc-crossref` for `@fig:`/`@tbl:` references, and LibreOffice for
Office files.

<details>
<summary>Without pipx</summary>

`pdfmd.py` is a single file that needs Python 3.10+ (with `pdfmd_inkmd/`
beside it for the no-Pandoc fallback). It also runs
directly, and `pyyaml`/`pypdf` are optional (features that need them are
skipped with a warning):

```sh
git clone https://github.com/aliperdehan/pdfmd.git ~/pdfmd
echo 'alias pdfmd="python3 ~/pdfmd/pdfmd.py"' >> ~/.zshrc   # or ~/.bashrc
```

macOS's built-in `/usr/bin/python3` is 3.9, which is too old; pdfmd says
so and exits.
</details>

Check what `pdfmd` can find on your system:

```console
$ pdfmd --check-dependencies
OK    pandoc  (/opt/homebrew/bin/pandoc)
OK    1. lualatex  (/Library/TeX/texbin/lualatex)
OK    2. xelatex  (/Library/TeX/texbin/xelatex)
OK    3. pdflatex  (/Library/TeX/texbin/pdflatex)
OK    4. latexmk  (/Library/TeX/texbin/latexmk)
OK    5. tectonic  (/opt/homebrew/bin/tectonic)
OK    6. typst  (/opt/homebrew/bin/typst)
OK    7. weasyprint  (/opt/homebrew/bin/weasyprint)
MISS  8. wkhtmltopdf
...
OK    14. soffice  (/Applications/LibreOffice.app/Contents/MacOS/soffice)
OK    quarto (only needed for .qmd files)  (/usr/local/bin/quarto)
```

The numbers are the fallback order, and also shortcuts: `-e 6` means
`-e typst`.

### No Pandoc? The built-in fallback

On a machine with no Pandoc, or Pandoc but no PDF engine, `pdfmd` does not
stop: it builds a plain PDF with a pure-Python renderer that `pip` installed
with it, and says so.

```console
$ pdfmd notes.md
NOTE  Pandoc was not found: building with the built-in renderer (inkmd). The output is plain ...
NATIVE  notes.md via inkmd
WARN  native (inkmd): notes.md: 2 math expression(s) set as plain text (Unicode, sub/superscripts, display math centred); ...
OK    notes.md
```

- **inkmd** is built in (vendored in `pdfmd_inkmd/`, about 2 MB, standard
  library only, works offline, same input gives the same bytes). It reads
  GitHub-flavoured Markdown: headings, emphasis, lists, task lists, tables,
  code blocks, quotes, links, images, and PNG/JPEG. It cannot typeset math,
  so formulas are set as readable text instead: Greek letters and operators
  as Unicode, `x^2` and `x_i` as super/subscripts, `\frac{a}{b}` as `a/b`,
  and display math (`$$...$$`, `\begin{equation}`, `aligned`) as its own
  centred lines. No bookmarks, no page numbers.
- **md2pdf** ([pymd2pdf](https://pypi.org/project/pymd2pdf/), ReportLab based) is
  used when installed, for documents with footnotes, math or a title:
  `pdfmd --install math` (same as `pip install "pdfmd-cli[math]"`; about
  150 MB, Python 3.11+, installs matplotlib so formulas render offline, centred,
  as real math; the few matplotlib cannot read are set as text like inkmd's).
  Footnotes, bookmarks and syntax-highlighted code come with it.
- `pdfmd --install emoji` (`pdfmd-cli[emoji]`, about 11 MB) adds the colour
  emoji font; without it emoji print as `[rocket]`-style labels.
- `pdfmd --install full` leaves the fallback behind: it installs **Pandoc** (the
  real binary from PyPI's `pypandoc_binary`, about 35 MB, also `--install pandoc`
  / `pdfmd-cli[pandoc]`) and **Typst** (Typst's own release from GitHub, about
  15 MB, also `--install typst`, checked against the SHA-256 GitHub lists) into
  pdfmd's own folders (`~/.local/share/pdfmd/bin`, `%LOCALAPPDATA%\pdfmd\bin`),
  with no admin rights. A Pandoc or Typst already on your PATH always wins; to
  remove them, `pip uninstall pypandoc_binary` and delete the `typst` file.

Every input is treated as GitHub-flavoured Markdown. Pandoc-only syntax is
converted where possible (`\newpage` and `<!-- pagebreak -->` become a page
break, footnotes become endnotes for inkmd, `$` prices are not mistaken for math)
and removed otherwise (heading and image attributes, `:::` divs, raw LaTeX,
`<!-- comments -->`), with one warning per kind. CSV tables
(`::: {.csv file="data.csv"}`) work as they do with Pandoc. The title, author and date in the
front matter become a title block and the PDF's own title and author; other
front-matter keys (`documentclass`, `header-includes`, `pdfmd-options`) are
listed as not used. There are no filters, preambles, citations, slides, parts or
report mode, and only Markdown input: for any of those, `pdfmd --install full`
(or `brew install pandoc typst`, `winget install JohnMacFarlane.Pandoc Typst.Typst`).

The built-in renderer is chosen automatically only when there is no Pandoc
route; a Pandoc build that fails never falls back to it. Ask for it with
`-e inkmd`, `-e md2pdf` or `-e native`, or `pdf-engine: inkmd` in `pdfmd-options`.
When it runs on a terminal and had to leave something out, `pdfmd` offers the
upgrades above (set `PDFMD_NO_PROMPT=1` to silence that; choosing "don't ask
again" remembers it).

## Usage

Every command below can be run from inside [`examples/`](https://github.com/aliperdehan/pdfmd/tree/main/examples/).

### One document

```sh
pdfmd lecture                 # finds lecture.md, writes lecture.pdf beside it
pdfmd lecture.md --open       # ...and opens it when done
pdfmd ~/notes/lecture.md -d   # write the PDF into the current directory instead
pdfmd lecture -w              # watch: rebuild on every save, until Ctrl+C
```

A bare name is looked up as `<name>.md`. The name can contain dots:
`pdfmd notes-v1.2` builds `notes-v1.2.md`.

If no file has exactly that name, pdfmd also looks at what each document is
called inside: its title, and any `pdfmd-options: {alias: ...}`. Case, spaces,
`_`, `-`, accents and script don't matter (`pdfmd animportantdocument` finds
`An Important Document.md`; `pdfmd glyukoza` finds a document titled
`Глюкоза`), and a unique *start* of a name or title works too, with a warning
saying what it matched (`pdfmd animp`, `pdfmd glucose`). A name that fits two
documents is an error, never a guess; `--no-auto lookup` switches the guessing
off. An exact file name always wins.

### One section

`pdfmd doc#onlyapart` builds just the section whose heading is "Only a Part"
(down to the next heading of the same or a higher level), written as
`doc.only-a-part.pdf` beside the document. Headings are named the way files
are: case, spaces and spelling don't matter, a unique start works (with a
warning), and so does a `{#label}`. `doc##yield` asks for a level-2 heading,
`doc#results/yield` for one under another, `doc#a+b` for several, and
`pdfmd '#yield'` uses the folder's only Markdown file. `pdfmd doc --list-parts`
shows what can be named. In a document split into parts the same names work
for headings inside the parts.

Anything with a `{#label}` can be named too: `pdfmd doc#fig:setup` builds just
that figure, `doc#eq:energy` that equation, and likewise a table, a fenced div,
a code block or a span (the figure's number restarts at 1).

### Other output formats

The format is taken from `-o`'s extension, or given explicitly with `--to`:

```sh
pdfmd lecture -o lecture.html
pdfmd lecture -o lecture.docx
pdfmd lecture --to typst -o lecture.typ
pdfmd lecture -o lecture.tex      # a complete, compilable .tex, not a fragment
```

### Stopping part-way

`--stop-at` ends the build after a stage; everything before it runs as normal:

```sh
pdfmd report --stop-at markdown   # report.assembled.md: the parts joined into one file
pdfmd report --assemble-only      # the same, shorter
pdfmd report --stop-at tex        # the standalone .tex a LaTeX engine would get (= --to latex)
```

The assembled file holds just the document text (and is marked
`pdfmd-assembled: true`), so pdfmd never joins its parts a second time.

By default it holds just the text. `--embed-metadata` also folds in what pdfmd
finds beside the document (metadata, preamble, Lua filters, and the
bibliography and CSL files the metadata names), so the file no longer needs
them beside it. What the text points at otherwise (images, files a preamble
`\input`s) is not embedded: keep it where the document finds it, relative to
the assembled file.

```sh
pdfmd report --assemble-only --embed-metadata                  # metadata.yaml, preamble.tex, Lua filters, .bib/.csl
pdfmd report --assemble-only --embed-metadata metadata preamble   # only those
pdfmd report --assemble-only --embed-metadata --lua-mode ref   # name the filter instead of copying it
```

An embedded Lua filter sits in a `{=pdfmd}` block at the end of the file. A
Lua filter can run any command, so one only runs if this machine's pdfmd
embedded it (otherwise it is skipped with a warning, unless you pass
`--trust-embedded`).

`--lua-mode apply` runs the filters at assembly time instead, so the text
already has their effect (approximate: Pandoc re-writes the text, and a filter
that looks at `FORMAT` is embedded instead). `--unpack` goes the other way:

```sh
pdfmd report.assembled.md --unpack     # filters, preamble and metadata back into report.assembled.unpacked/
```

`pdfmd` finds `report.assembled.unpacked/` beside `report.assembled.md` by
itself (its metadata, preambles and Lua filters), and `--unpack --slim` strips
the unpacked parts out of the assembled file, leaving the lean document plus
that folder.

A document can name its own files and set what to embed, in `pdfmd-options`:

```yaml
pdfmd-options:
  yaml: [base.yaml]        # metadata files (like -y); also `metadata:`, or grouped:
  metadata:
    preamble: my-preamble.tex
    lua-filter: my.lua
  embed: {lua: ref}        # what --assemble-only embeds without the flag
```

Plain HTML output is a fragment. For a finished page, or one file with
everything (images, CSS) inlined, ask for it, on the command line or in the
document:

```sh
pdfmd lecture -o lecture.html --self-contained
```

```yaml
pdfmd-options:
  default-output: html     # build to HTML when no format is given
  html: {self-contained: true, css: style.css}
```

### Slides

```sh
pdfmd slides -p                   # Beamer slides; each heading starts a slide
```

<p align="center">
  <img src="https://raw.githubusercontent.com/aliperdehan/pdfmd/main/docs/slides.png" width="380" alt="A Beamer slide from examples/slides.md">
</p>

### A whole folder

```console
$ pdfmd notes -b
AUTO: READER TITLE MARGIN MONOFONT. Use --verbose to see in full
AUTO: MARGIN. Use --verbose to see in full
AUTO: MARGIN. Use --verbose to see in full
OK    notes/lecture.md
OK    notes/week1.md
OK    notes/week2.md
```

`-b` converts every `.md` in the folder into its own PDF, in parallel
(`-j N` sets the number of workers). Add `--recursive` to include
subfolders, and `-o DIR` to collect the PDFs somewhere else.

### A book or report from several files

```console
$ pdfmd book -r -o book.pdf
OK    book/01-intro.md
OK    book/02-methods.md
AUTO: MARGIN. Use --verbose to see in full
OK    REPORT  book.pdf
```

`-r` (also spelled `--report` or `--book`) joins every `.md` in the folder
into a single PDF, in the order of each file's `chapter:` front-matter
field. See [`examples/book/`](https://github.com/aliperdehan/pdfmd/tree/main/examples/book/). `-i FILE` leaves one file
out, and `--exclude-unnumbered` skips files without a `chapter:`.

### One long document in several files

For an article-style document that has grown too long to edit as one file
(and unlike `-r`, one that should read as a single document, not a
sequence of chapters), keep a *scaffold* with the front matter, and the
text in a `parts/` folder beside it, one file per section, each starting with
its own heading:

```
report.md                    front matter only (title, author, ...)
parts/10-introduction.md
parts/20-methods.md
parts/30-discussion.md
```

Switch it on once, in a `metadata.yaml` shared by your documents, so the
content files carry no typesetting:

```yaml
pdfmd-options:
  parts: auto        # a document is a scaffold only if parts/ or sections/ exists
```

```console
$ pdfmd report                  # the whole document, report.pdf
$ pdfmd report#methods          # just that part, report.methods.pdf
$ pdfmd report#discussion+appendix      # several: always in report order
$ pdfmd parts/20-methods.md     # same as report#methods
$ pdfmd report --list-parts
$ pdfmd old-report.md --split new-folder   # cut an existing single file into parts
$ pdfmd old-report.md --split new-folder --split-depth 2   # ...and subsections too
```

The parts are joined in filename order into one Pandoc run, so the result is
identical to the same text in a single file: labels, citations and numbering
work across parts, and paths are written relative to the scaffold's folder
whichever part they are in. A part rebuilt alone is much faster to compile
but cannot see the others, so references to them print as `??`. See
[`examples/parts/`](https://github.com/aliperdehan/pdfmd/tree/main/examples/parts/).

#### Faster rebuilds: the cache

```yaml
pdfmd-options:
  cache: {aux: true}      # or: pdfmd report --cache
```

keeps LaTeX's cross-reference files between builds (in `~/.cache/pdfmd`), so
an unchanged document is typeset once instead of two or three times, and a
part built on its own shows the real numbers of the parts left out (taken
from the last full build) instead of `??`. It never skips a build: Pandoc and
LaTeX still process the whole document from the current sources and package
every time, so a change shows in the next build. `cache: {plots: true}` (or
`--cache-plots`, with nulabreport >= 1.26.0) additionally stores each plot as a
PDF and reuses it until the package, the preamble, the engine or the plot's
data file changes. Off by default; `--no-cache` for one build; `pdfmd --clear-cache`
(or deleting the folder) is always safe.

### Tables straight from a CSV file

```markdown
Measured values:

::: {.csv file="data.csv"}
:::
```

<p align="center">
  <img src="https://raw.githubusercontent.com/aliperdehan/pdfmd/main/docs/results.png" width="480" alt="A CSV file rendered as a table">
</p>

- The delimiter is detected from the extension (`.tsv` means tab), or set
  with `delimiter=";"`.
- The first row is the header unless you add `header="false"`.
- Large files are capped at 10 rows × 7 columns, so a huge CSV can't
  silently fill 40 pages. `rows=all` or `cols=20` raise the cap. When a
  table is cut, the PDF itself shows a note saying so.

This works for every output format.

### Not just Markdown

```sh
pdfmd paper.tex          # compiled directly with a LaTeX engine: reruns until
                         # references settle, runs bibtex/biber, and leaves
                         # no .aux/.log clutter (--keep-aux keeps them)
pdfmd minutes.docx       # Word/PowerPoint/Excel/ODF: converted by LibreOffice
pdfmd analysis.qmd       # handed to Quarto, so code chunks actually run
pdfmd page.html          # anything else Pandoc can read (give the extension)
```

## What it does automatically

Most of these print an `AUTO` line, and each can be switched off individually.

| `AUTO` kind | When | What happens |
|---|---|---|
| `READER` | no YAML front matter | reads the file as GitHub-flavoured Markdown (content-sized table columns, relaxed blank-line rules) |
| `TITLE` | no front matter, first line is `# Title` | that heading becomes the document title, and the remaining headings move up one level |
| `MARGIN` | no margin or geometry set anywhere | 1-inch margins instead of LaTeX's wide defaults |
| `MAINFONT` | no `mainfont:` and no `-f` | STIX Two Text, retried with DejaVu Serif if any glyph is missing (Times New Roman if DejaVu isn't installed) |
| `MONOFONT` | the document contains code | JetBrains Mono for code (Menlo or another installed monospace font if it isn't installed) |
| `tablewidth` | a wide pipe table | balances column widths so the table fits the page, and leaves narrow tables at their natural width |
| `YAML` / `TEX` / `LUA` | project files found | attaches `metadata.yaml`, `preamble.tex`, `<name>.lua` (see below) |
| `citeproc` | `@key` / `[@key, p. 90]` citations | adds `--citeproc`, so citations and the reference list render from your `bibliography:` without any flag (`--no-citeproc` turns it off) |
| `crossref` | `@fig:`/`@tbl:` references | adds the `pandoc-crossref` filter, ahead of citeproc |
| `papersize` | `pagesize: a4` (a common typo) | converts it to Pandoc's real `papersize:` |

`-v` explains each decision and prints the exact command it runs:

```console
$ pdfmd lecture -v
CMD  pandoc lecture.md -o lecture.pdf --pdf-engine=lualatex -f gfm -V 'mainfont=STIX Two Text' -V geometry:margin=1in -V 'monofont=JetBrains Mono' --shift-heading-level-by=-1 --lua-filter .../pdfmd-tablewidth.lua
CMD  pandoc lecture.md -o lecture.pdf --pdf-engine=lualatex -f gfm -V 'mainfont=DejaVu Serif' ...
AUTO READER  lecture.md: no YAML front matter; reading as gfm
AUTO TITLE  lecture.md: promoted leading '# ' heading to Pandoc title metadata
AUTO MARGIN  lecture.md: no geometry/margin set; using geometry:margin=1in on LaTeX-family engines
AUTO MONOFONT  lecture.md: has code but no monofont set; using JetBrains Mono on LaTeX-family engines
OK    lecture.md
```

The second `CMD` line is the font fallback at work: STIX Two Text was
missing a glyph, so the document was rebuilt with DejaVu Serif. (Temporary
file paths are shortened here.)

**When a PDF doesn't look the way the Markdown suggests, run `-v` first.**
The cause is usually one of these automatic decisions, and `-v` names it.

### Switching defaults off

```sh
pdfmd lecture --no-auto                  # everything off: close to plain pandoc
pdfmd lecture --no-auto margin mainfont  # only these
```

### Passing options to Pandoc

Any option `pdfmd` doesn't recognise is passed straight to Pandoc:

```sh
pdfmd lecture --toc --number-sections
pdfmd lecture -V fontsize=12pt
```

### Settings inside the document

Or put settings in the document itself, so nobody has to remember the flag:

```yaml
---
title: Lab report
pdfmd-options:
  no-auto: [margin, monofont]
  pdf-engine: tex        # only TeX engines; never fall back to HTML ones
---
```

`pdf-engine:` takes an engine name (`lualatex`, `typst`, ...) or a family:
`tex`, `typst`, `html` or `office`. A family limits the fallback chain to
that kind of engine. For example, a document full of chemical structures
can require TeX, and a plain memo can skip the slow LaTeX run. `-e` on the
command line always wins, and a bare `-e` means "try every engine".

## Project files

`pdfmd` looks next to the document, and in a `metadata/` folder beside it,
for:

| File | Used as |
|---|---|
| `metadata.yaml` | shared Pandoc metadata (fonts, bibliography, CSL, ...) |
| `<name>.yaml` | per-document metadata, layered on top of `metadata.yaml` |
| `report.yaml` / `book.yaml` | metadata for `-r` builds |
| `preamble.tex`, `latex-preamble.tex`, `<name>-preamble.tex`, `preamble-*.tex` | LaTeX added to the header, generic files first |
| `<name>.lua` | a Pandoc Lua filter for that document |

**Only these names are picked up automatically.** An unrelated `.lua` or
`.tex` file lying in the folder never changes a render. When several YAML
files could apply and none is clearly meant, `pdfmd` stops and asks you to
choose with `-y FILE`, rather than guessing. `-y` alone turns discovery
off.

With a `metadata/` folder, a report's own folder can hold nothing but
`report.md` and `report.pdf`. Relative paths inside the metadata (such as
`bibliography: refs.bib`) resolve from `metadata/`, and image paths in the
document still resolve from the document's own folder.

One shared metadata file can also be **symlinked** into many folders. A
relative `bibliography: refs.bib` inside it then finds the `refs.bib`
next to the file's real copy, so you never need an absolute path.

## Build stamps and snapshots

Both are off by default.

- **`--stamp`** keeps a `BUILD NOTES` HTML comment at the end of the `.md`
  up to date. It records when the document was compiled and with which
  `pdfmd` version, plus the versions of any LaTeX packages you name with
  `--stamp-packages`. The comment is invisible in the PDF. `--stamp-mode history` also keeps a list of past compiles.
- **`--backup`** saves a timestamped copy of the source into `backup/`
  after every successful build. A copy is skipped when nothing changed,
  and `keep: 30` limits how many are kept.

Both can be turned on for a whole folder from `metadata.yaml`:

```yaml
pdfmd-options:
  stamp: true
  backup: { dir: backup, keep: 30 }
```

Separately, when `pypdf` is installed, every PDF built by `pdfmd` gets two
hidden metadata keys, `PdfmdVersions` and `PdfmdBuildDate`, which you can
read with `pdfinfo -meta`. Turn this off with `--no-stamp-pdf-metadata`.

## Reference

- `pdfmd --help` lists every flag.
- The docstring at the top of [`pdfmd.py`](https://github.com/aliperdehan/pdfmd/blob/main/pdfmd.py) is the full reference
  for each behaviour and its edge cases.
- [`CHANGELOG.md`](https://github.com/aliperdehan/pdfmd/blob/main/CHANGELOG.md) records what changed in each version and
  why.

## License

[MIT](https://github.com/aliperdehan/pdfmd/blob/main/LICENSE)
