Convert a simple CSV File with PHP, list of different possible ways how to reformat a simple csv

csv-format-pure.php

<?php
$start = microtime(true);

$fpIn  = fopen('input.csv', 'r');
$fpOut = fopen('output-pure.csv', 'w');

while (($row = fgets($fpIn)) !== false) 
{
	$fields = explode(";", $row);
	fwrite($fpOut, 
		implode(
			";",
			array(
				"name"           => $fields[0],
				"firstname name" => '"'.$fields[1] ." ". $fields[0].'"',
				"kto"            => $fields[2],
				"blz"            => $fields[3],
				"amount"         => $fields[4]
			)
		)
	);
}

$end = microtime(true);

$duration = $end - $start;
echo "Duration: ".round($duration, 2) . "s".PHP_EOL;

csv-format.php

<?php
$start = microtime(true);

$fpIn  = fopen('input.csv', 'r');
$fpOut = fopen('output.csv', 'w');

while (($row = fgetcsv($fpIn, 0, ";")) !== false) 
{
	fputcsv($fpOut, array(
		"name"           => $row[0],
		"firstname name" => $row[1] ." ". $row[0],
		"kto"            => $row[2],
		"blz"            => $row[3],
		"amount"         => $row[4]
	), ";");
}

$end = microtime(true);

$duration = $end - $start;
echo "Duration: ".round($duration, 2) . "s".PHP_EOL;

csv-gen-filter.php

<?php
// reformat the csv file via a filter
$start = microtime(true);


$fpIn  = fopen('input.csv', 'r');
$fpOut = fopen('output.csv', 'w');
stream_filter_register("csvreformat", "csvreformat_filter");
stream_filter_append($fpIn, "csvreformat");
stream_copy_to_stream($fpIn, $fpOut);


$end = microtime(true);
$duration = $end - $start;
echo "Duration: ".round($duration, 2) . "s".PHP_EOL;

class csvreformat_filter extends php_user_filter {
  private $remaining = ""; 
  
  function filter($in, $out, &$consumed, $closing)
  {
    while ($bucket = stream_bucket_make_writeable($in)) 
    {    
      $data = $this->remaining.$bucket->data;
      $lastNewLine = strrpos($data, PHP_EOL);
	  $this->remaining = substr($data, $lastNewLine+1);
      $data = substr($data, 0, $lastNewLine);  
      $bucket->data = "";
      foreach(explode(PHP_EOL, $data) as $row) 
      {
		$tmp = explode(";", $row);
		$bucket->data .= $tmp[0].';"'.$tmp[1]." ".$tmp[0].'";'.$tmp[2].";".$tmp[3].";".$tmp[4].PHP_EOL;
      }
      $consumed += $bucket->datalen;
      stream_bucket_append($out, $bucket);
    }
    return PSFS_PASS_ON;
  }
}

csv-gen.php

<?php
$start = microtime(true);

$fp = fopen('input.csv', 'w');

for ($i = 1; $i <= 1000000; $i++) 
{
	$row = array(
		"name"      => someString(),
		"firstname" => someString(),
		"kto"       => rand(1000000, 9999999),
		"blz"       => rand(1000000, 9999999),
		"amount"    => rand(1000000, 9999999)
	);
	
	fputcsv($fp, $row, ";");
}

$end = microtime(true);

$duration = $end - $start;
echo "Duration: ".round($duration, 2) . "s".PHP_EOL;

function someString($length = 10) {
	return substr(md5(rand()), 0, $length);
}