Allows deleting of all keys in a riak bucket using the streaming api

truncate.php

<?php
/**
 * Delete all keys from a riak bucket using key streaming
 * 
 * History:
 * 
 *		29-Nov-10
 *			First version
 * 
 * @author Russell Smith <russell.smith@ukd1.co.uk>
 * @copyright UKD1 Limited 2010
 * @license licence.txt ISC license
 * @see https://gist.github.com/gists/720565
 */

// comment this out, just incase you run it and trash something useful...
die('You should have commented this out...');
 
// Enter your riak URL here, including the bucket...
define('RIAK_URL', 'http://127.0.0.1:8098/riak/test/');

// You shouldn't need to change this, it allows extracting the
// json block of keys from the stream.
define('REGEX', '~'.preg_quote('{"keys":[').'(.+?)\]\}~');


// Init curl, 5 sec timeout...?
$ch = curl_init();
curl_setopt($ch, CURLOPT_TIMEOUT, 5);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'DELETE');


// delete the specified key
function delete($key) {
	global $ch;

	curl_setopt($ch, CURLOPT_URL, RIAK_URL . $key);
	curl_exec($ch);
	$tmp = curl_getinfo($ch);

	return $tmp['http_code'] === 204;
}


// stream the keys
$f = fopen(RIAK_URL . '?keys=stream&props=false', 'r');

// empty buffer
$buf = '';

// stream whilst not eof
while (!feof($f)) {
	// read 1024 bytes
	$buf .= fgets($f, 1024);

	// repeatedly check for matches against the buffer
	// as sometimes you might get two json blocks in 
	// the read size
	while (preg_match(REGEX, $buf, $matches)) {
		// decode
		$result = json_decode($matches[0]);
		
		// run through each key and delete
		array_map(function($k){
			print "$k\t" . (delete($k) ? '[deleted]' : '[failed]') . "\n";
		}, $result->keys);

		// remove the keys we've just processed from the block
		$buf = substr($buf, strlen($matches[0]));
	}
}

// close
fclose($f);