pogo: Run PHP scripts with inline dependencies

Pogo allows you to write small PHP scripts which use PHP libraries (courtesy of composer/packagist)... but it doesn't require you setup a special-purpose folder, project, or repository. To use a dependency, simply add a small pragma into your script. This makes it easier to use PHP libraries when:

• Experimenting or learning
• Writing random system-automation scripts and one-off scripts

Example

Let's pick a small task that requires a few libraries -- suppose we want to generate a pretty PDF from a source-code file (.php, *.json, etc). We'll need a pretty-printer (scrivo/highlight.php) and a PDF generator (dompdf/dompdf).

Skimming the README for each library, one finds a few introductory snippets. I took these, added the #!require pragmas, and improvised a little on the $html variable. This becomes a small script, code2pdf.php:

<?php
$code = file_get_contents('php://stdin');

#!require scrivo/highlight.php: ~9.15
$hl = new \Highlight\Highlighter();
$hl->setAutodetectLanguages(['php', 'css', 'yaml', 'json', 'js']);
$highlighted = $hl->highlightAuto($code);
$html = sprintf('<link rel="stylesheet" href="file://%s"/>', \HighlightUtilities\getStyleSheetPath('sunburst.css'));
$html .= sprintf("<pre><code class=\"hljs %s\">%s</code></pre>", $highlighted->language, $highlighted->value);

#!require dompdf/dompdf: ~0.8.3
$dompdf = new \Dompdf\Dompdf();
$dompdf->loadHtml($html);
$dompdf->setPaper('A4', 'landscape');
$dompdf->render();
$dompdf->stream();

To run this script in the CLI, just use:

pogo code2pdf.php

Of course, this script expects some content as input (e.g. myfile.yml) and produces a PDF as output (e.g. myfile.pdf), so a more realistic command would be

cat myfile.yml | pogo code2pdf.php > myfile.pdf

That's it!

Motivation

Most of my day-to-day work is in PHP, JS, and bash. From time-to-time, one needs a bit of glue-code for one-offs, and I find myself avoiding PHP for that task... because using a library in PHP still requires bits of administrativa. pogo is an experiment to reduce that administrativa. Just create a .php file and run it.

More information

• Installation: System requirements and install steps
• Composer integration: How pogo works with composer
• Execution: Ways to invoke scripts via pogo
• FAQ: Frequently asked questions
• Pragmas: List of all supported pragmas
• Todo: Misc things that should be done