Simple download function for PHP

README.md

Usage

$url = 'http://some.url/file.txt';
$data = download($url, $headers, $err_msg);
if( !$data ) {
  echo $err_msg;
  die;
}

print_r($headers);
echo stream_get_contents($data);

This is conceptually similar to:

echo stream_get_contents(fopen($url, 'r'))

The differences are:

• We can get better error info.
• We can get the HTTP headers so we know things like the content type.
• Since we are using the curl library it works even when fopen doesn't allow URLs.

download.php

<?php
# https://gist.github.com/eric1234/37fd102798d99d94b0dcebde6bb29ef3
#
# Abstracts the idiocy of the CURL API for something simpler. Assumes we are
# downloading data (so a GET request) and we need no special request headers.
# Returns an IO stream which will be the data requested. The headers of the
# response will be stored in the $headers param reference.
#
# If the request fails for some reason FALSE is returned with the $err_msg
# param containing more info.
function download($url, &$headers=[], &$err_msg) {
  $io = curl_init($url);
  $stream = fopen('php://temp', 'w+');

  curl_setopt_array($io, [
    CURLOPT_FAILONERROR    => true,
    CURLOPT_FOLLOWLOCATION => true,
    CURLOPT_HEADER         => true,
    CURLOPT_FILE           => $stream,
  ]);

  if( curl_exec($io) === false ) {
    $err_msg << curl_error($io);
    return false;
  }

  curl_close($io);
  rewind($stream);

  $line = trim(fgets($stream));
  if( preg_match('/^HTTP\/([^ ]+) (.*)/i', $line, $matches) ) {
    $headers['HTTP_VERSION'] = $matches[1];
    $headers['STATUS'] = $matches[2];
  }

  while( $line = fgets($stream) ) {
    if( preg_match('/^\s+$/', $line) ) break;
    list($key, $value) = preg_split('/\s*:\s*/', $line, 2);
    $headers[strtoupper($key)] = trim($value);
  }

  return $stream;
}