PHP - validate mustache template

Question

How do I validate a mustache template string in PHP? For example, if I pass

Hi {{#name}}{{name}}{{/name}}{{^name}}guest{{/name}}

and the validator should return valid, but if I pass

Hi {{#name}}{{name}}{{/name}}{{^name}}guest

it should return invalid.

Note I'd rather this to be done fully in PHP with no Mustache_Engine or any other 3rd party dependency.

short answer: write your own Mustache Engine. (tip: it's easier and less error prone to just use an existing library) — Kaii, Sep 12 '16 at 19:18

score 0 · Answer 1 · answered Sep 12 '16 at 18:56

0

Just compile it:

function validate($template) {
    $m = new Mustache_Engine;
    try {
        $m->getParser()->parse($m->getTokenizer()->scan($template));
        $valid = true;
    } catch (Mustache_Exception_SyntaxException $e) {
        $valid = false;
    }
    return $valid;
}

answered Sep 12 '16 at 18:56

Alex Blex

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I'll update my comment, but I do not want to use any other packages. – Kousha Sep 12 '16 at 19:03
Then please update your question once again and show what you have tried so far. – Alex Blex Sep 12 '16 at 22:27

score 0 · Accepted Answer · answered Sep 13 '16 at 16:57

It's not possible to correctly validate all valid mustache templates without building a mustache parser. There is no regular expression shortcut. You need an actual parser.

If you're okay with some false negatives (and some false positives) you could build something to validate a subset of them. Or you can build a proper parser. But your best bet is to use mustache.php to parse it, as indicated in other answers.

Why are you trying to do this without any dependencies?

PHP - validate mustache template

2 Answers2