Some research on pdf conversion

modules/microsite/docs/dev/adr/0007_convert_html_files.md

@@ -0,0 +1,71 @@
+---
+layout: docs
+title: Convert HTML Files
+---
+
+# {{ page.title }}
+
+## Context and Problem Statement
+
+How can HTML documents be converted into a PDF file that looks as much
+as possible like the original?
+
+It would be nice to have a java-only solution. But if an external tool
+has a better outcome, then an external tool is fine, too.
+
+Since Docspell is free software, the tools must also be free.
+
+
+## Considered Options
+
+* [pandoc](https://pandoc.org/) external command
+* [wkhtmltopdf](https://wkhtmltopdf.org/) external command
+* [Unoconv](https://github.com/unoconv/unoconv) external command
+
+Native (firefox) view:
+
+<div class="thumbnail">
+  <img src="./img/example-html-native.jpg" title="Native view of an HTML example file">
+</div>
+
+Note: the example html is from
+[here](https://www.sparksuite.com/open-source/invoice.html).
+
+I downloaded the HTML file to disk together with its resources (using
+*Save as...* in the browser).
+
+
+### Pandoc
+
+<div class="thumbnail">
+  <img src="./img/example-html-pandoc-latex.jpg" title="Pandoc (Latex) HTML->PDF">
+</div>
+
+<div class="thumbnail">
+  <img src="./img/example-html-pandoc-html.jpg" title="Pandoc (html) HTML->PDF">
+</div>
+
+Not showing the version using `context` pdf-engine, since it looked
+very similiar to the latex variant.
+
+
+### wkhtmltopdf
+
+<div class="thumbnail">
+  <img src="./img/example-html-wkhtmltopdf.jpg" title="wkhtmltopdf HTML->PDF">
+</div>
+
+
+### Unoconv
+
+
+<div class="thumbnail">
+  <img src="./img/example-html-unoconv.jpg" title="Unoconv HTML->PDF">
+</div>
+
+
+## Decision Outcome
+
+wkhtmltopdf.
+
+It shows the best results.