Get the raw text content from a markdown file to use elsewhere in your code. Made for use in conjunction with the erusev/parsedown composer package.

print_md.php

<?php
/** Print Markdown
  * Author: Jordan Brauer <jbrauer.inc@gmail.com>
  * Function: print_md()
  * Description: get the raw text content from a markdown file
  * to use elsewhere in your code.
  *
  * Note: Made for use in conjunction with the erusev/parsedown composer package.
  */

function print_md ($file)
{
  // check if $file exists
  if (file_exists($file)) {
    // get file extension of $file and assign to a variable.
    $info = new SplFileInfo($file);
    $ext = $info->getExtension();

    // supported markdown extensions to check $ext against.
    $supported_ext = array(
      'markdown',
      'mdown',
      'mkdn',
      'md',
      'mkd',
      'mdwn',
      'mdtxt',
      'mdtext',
      'text',
      'Rmd',
    );

    // check $ext against the $supported_ext array.
    if (in_array($ext, $supported_ext)) {
      // if the file is indeed markdown, assign its' contents to a variable for returning.
      $md = file_get_contents($file);
      return $md;
    }

    // throw error if the extension is not in the list and return false.
    throw new Exception('The file ' . $file . '\'s extension is not a supported markdown file extension.');
    return false;
  }

  // throw an error if the file does not exist and return false.
  throw new Exception('The file ' . $file . ' does not exist.');
  return false;
}