https://github.com/fastify/safe-regex2
detect possibly catastrophic, exponential-time regular expressions
https://github.com/fastify/safe-regex2
fastify-fork fastify-library
Last synced: 5 months ago
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detect possibly catastrophic, exponential-time regular expressions
- Host: GitHub
- URL: https://github.com/fastify/safe-regex2
- Owner: fastify
- License: other
- Created: 2019-02-18T05:22:22.000Z (about 7 years ago)
- Default Branch: master
- Last Pushed: 2024-07-12T12:12:17.000Z (over 1 year ago)
- Last Synced: 2024-09-28T11:20:59.093Z (over 1 year ago)
- Topics: fastify-fork, fastify-library
- Language: JavaScript
- Homepage:
- Size: 47.9 KB
- Stars: 35
- Watchers: 5
- Forks: 3
- Open Issues: 1
-
Metadata Files:
- Readme: readme.markdown
- License: LICENSE
Awesome Lists containing this project
README
# safe-regex2
detect potentially
[catastrophic](http://regular-expressions.mobi/catastrophic.html)
[exponential-time](http://perlgeek.de/blog-en/perl-tips/in-search-of-an-exponetial-regexp.html)
regular expressions by limiting the
[star height](https://en.wikipedia.org/wiki/Star_height) to 1
This is a fork of https://github.com/substack/safe-regex at 1.1.0.
WARNING: This module has both false positives and false negatives.
It is not meant as a full checker, but it detect basic cases.
# example
``` js
var safe = require('safe-regex2');
var regex = process.argv.slice(2).join(' ');
console.log(safe(regex));
```
```
$ node safe.js '(x+x+)+y'
false
$ node safe.js '(beep|boop)*'
true
$ node safe.js '(a+){10}'
false
$ node safe.js '\blocation\s*:[^:\n]+\b(Oakland|San Francisco)\b'
true
```
# methods
``` js
var safe = require('safe-regex')
```
## var ok = safe(re, opts={})
Return a boolean `ok` whether or not the regex `re` is safe and not possibly
catastrophic.
`re` can be a `RegExp` object or just a string.
If the `re` is a string and is an invalid regex, returns `false`.
* `opts.limit` - maximum number of allowed repetitions in the entire regex.
Default: `25`.
# install
With [npm](https://npmjs.org) do:
```
npm install safe-regex2
```
# license
MIT