Valve Data Format VDF to JSON

Valve stores a lot of its data for games in VDF format, its own internal data format that is very JSON-esque. I first ran into it parsing through the items_game.txt file for Dota 2.

So today I created a quick PHP script which will allow you to create valid JSON from VDF data, so you can parse it much more easily and hopefully make better use of it!

<?php //load VDF data either from API call or fetching from file/url //no matter your method, $json must contain the VDF data to be parsed $json = file_get_contents("items_game.txt"); //encapsulate in braces $json = "{\n$json\n}"; //replace open braces $pattern = '/"([^"]*)"(\s*){/'; $replace = '"${1}": {'; $json = preg_replace($pattern, $replace, $json); //replace values $pattern = '/"([^"]*)"\s*"([^"]*)"/'; $replace = '"${1}": "${2}",'; $json = preg_replace($pattern, $replace, $json); //remove trailing commas $pattern = '/,(\s*[}\]])/'; $replace = '${1}'; $json = preg_replace($pattern, $replace, $json); //add commas $pattern = '/([}\]])(\s*)("[^"]*":\s*)?([{\[])/'; $replace = '${1},${2}${3}${4}'; $json = preg_replace($pattern, $replace, $json); //object as value $pattern = '/}(\s*"[^"]*":)/'; $replace = '},${1}'; $json = preg_replace($pattern, $replace, $json); //we now have valid json which we can use and/or store it for later use file_put_contents("items_game.json", $json); /* NB: this does not allow for creation of json arrays, however. * if you wish to keep working with the json data in PHP, you could * do something like this to get an array where needed. eg. for items */ $data->items_game->items = get_object_vars($data->items_game->items); //items object is now an array ?>

For those who would like to do this, but in a separate language here’s the series of regular expressions I applied, after first encapsulating the entire string in curly braces. NB: ${n} in the replacement is specifying a callback where n is the n’th matched item in the expression. There may be a different call back specification in your preferred language.

1) pattern: '/"([^"]*)"(\s*){/'
   replacement: '"${1}": {'
2) pattern: '/"([^"]*)"\s*"([^"]*)"/'
   replacement: '"${1}": "${2}",'
3) pattern: '/,(\s*[}\]])/'
   replacement: '${1}'
4) pattern: '/([}\]])(\s*)("[^"]*":\s*)?([{\[])/'
   replacement: '${1},${2}${3}${4}'
5) pattern: '/}(\s*"[^"]*":)/'
   replacement: '},${1}'

To the best of my knowledge these regular expressions cover all of VDF, but I cannot guarantee they will work forever. However if it ceases to work I will update it as soon as I notice/am informed.

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