ohaitch / nginx-cache

Find files in an Nginx cache based on partial URL keys

nginx-cache

A Node.js module that recursively scans the directories and files of an Nginx cache as efficiently as possible looking for partial URL key matches based on a regular expression.

Install

npm install nginx-cache

Usage example

Purge all CSS files from an Nginx cache:

var nginxCache = require('nginx-cache');

nginxCache('/var/www/cache')
  .find(/.css$/)
  .on('match', function(file, url) {
    console.log('Attempting to remove cached version of ' + url);
    fs.unlink(file, function(err) {
      if (err) {
        console.log(err.message);
      }
    });
  })
  .on('error', function(err) {
    console.log(err.message);
  })
  .on('finish', function() {
    console.log('Done');
  });

API

nginxCache(directory)

Constructor to which further methods are chained.

• directory is the path to the Nginx cache, as provided to its proxy_cache_path directive.

find(pattern)

• pattern is an instance of a standard JavaScript RegExp object.

on(event, listener)

Register a function to listen for the given event, where:

• event is a String containing the name of the event (see below), and
• listener is a function to call when the event is emitted.

Event: 'match'

The match event is emitted when a cache file matching the pattern passed to find() is found.

The event attributes are file, url where:

• file is the full path to the matching cache file, and
• url is the full cache key that matched the pattern.

Event: 'finish'

The finish event is emitted when all cache directories and files have been scanned. No further events are emitted after this.

Event: 'error'

The error event is emitted when a non-ignorable problem occurs, e.g. lack of permission to read files in the cache directory.

Event: 'warn'

The warn event is emitted when an ignorable problem occurs, e.g. the Nginx cache manager deleted a file.

Alternatives

If you know the complete, original cache key then the commercial Plus version of Nginx provides a proxy_cache_purge directive, which may be more suitable.

Licence

Copyright 2015 Dispatches LLP.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.