node-cachew

In-memory value caching for expiring keys and an efficient range index.

Installation And Use

$ npm install cachew

ChainCache

Useful for simple refs expiring on a uniform timeout. Uses a linked-list configuration.

var example = new require('cachew').ChainCache (
    100000,         // maximum key count
    1000 * 60 * 5,  // store for five minutes
    true            // renew keys when read
);
http.createServer (function (request, response) {
    // cache whole requests by ip
    example.set (
        request.connection.remoteAddress,
        request
    );
 
    // process request
});

DocumentChainCache

Used for complex Object refs which must be indexed on more than one key. Basically a ChainCache under the hood.

var example = new require('cachew').DocumentChainCache (
    [ 'remoteAddress' ],
    100000,         // maximum key count
    1000 * 60 * 5,  // store for five minutes
    true            // renew keys when read
);
http.createServer (function (request, response) {
    // cache connection information by ip
    example.set (request.connection);
 
    // process request
});

RangeIndex

When you need to store and retrieve values by numerical fit, use a RangeIndex.

var example = new require('cachew').RangeIndex (
    100000 // maximum key count
);
var points = [
    { x:10,     y:15.3,     data:payload_01},
    { x:4.81,   y:7,        data:payload_02},
    { x:100,    y:153,      data:payload_03},
]
for (var i in points) {
    // map points by distance from the origin
    var point = points[i];
    var distance = Math.sqrt(
        Math.pow (point.x, 2)
      + Math.pow (point.y, 2)
    );
    example.set (distance, point);
}
 
// select all points within a hollow circle
// centered on the origin
console.log (example.getRange (10, 30));

Development

cachew is developed and maintained by Kevin "Schmidty" Smith under the MIT license. If you want to see continued development, please help me pay my bills!

LICENSE

The MIT License (MIT)

Copyright (c) 2015 Kevin "Schmidty" Smith

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.