Titanium Module Cache CommonJS module - Plug n Play - Easy Cache

cache.js

/***************************************************
Titanium Cache Module

Modified By: Justin Greer
https://justin-greer.com

Original Author: Joe Maffia
http://about.me/joemaffia

A cache module to be used for Titanium app. http://www.appcelerator.com/
It uses the local SQLite database to cache strings and JavaScript objects.

Usage: 
Place this file (cache.js) in the project "lib" folder. You must create this folder if it does not exist.

Load the module
var cache = require('cache');

cache.put('key', 'value', 3600);
cache.get('key');
cache.del('key');
......
***************************************************/
var Cache = function() {}

// Cache initialization
Cache.prototype.initCache = function(cache_expiration_interval) {
  var db = Titanium.Database.open('cache');
  db.execute('CREATE TABLE IF NOT EXISTS cache (key TEXT UNIQUE, value TEXT, expiration INTEGER)');
  db.close();
  Ti.API.info('[CACHE] INITIALIZED');
};

Cache.prototype.expireCache = function() {
  var db = Titanium.Database.open('cache');
  var timestamp = currentTimestamp();

  // count how many objects will be deleted
  var count = 0;
  var rs = db.execute('SELECT COUNT(*) FROM cache WHERE expiration <= ?', timestamp);
  while (rs.isValidRow()) {
    count = rs.field(0);
    rs.next();
  }
  rs.close();

  // deletes everything older than timestamp
  db.execute('DELETE FROM cache WHERE expiration <= ?', timestamp);
  db.close();

  Ti.API.debug('[CACHE] EXPIRATION: [' + count + '] object(s) expired');
};

Cache.prototype.currentTimestamp = function() {
  var value = Math.floor(new Date().getTime() / 1000);
  Ti.API.debug("[CACHE] currentTimestamp=" + value);
  return value;
};

Cache.prototype.get = function(key) {
  var db = Titanium.Database.open('cache');

  var rs = db.execute('SELECT value FROM cache WHERE key = ?', key);
  var result = null;
  if (rs.isValidRow()) {
    Ti.API.info('[CACHE] GET: key[' + key + ']');
    result = JSON.parse(rs.fieldByName('value'));
  } else {
    Ti.API.info('[CACHE] Missed: key[' + key + ']');
  }
  rs.close();
  db.close();

  return result;
};

Cache.prototype.put = function(key, value, expiration_seconds) {
  if (!expiration_seconds) {
    expiration_seconds = 300;
  }
  var expires_in = currentTimestamp() + expiration_seconds;
  var db = Titanium.Database.open('cache');
  Ti.API.info('[CACHE] PUT: time=' + currentTimestamp() + ', expires_in=' + expires_in);
  var query = 'INSERT OR REPLACE INTO cache (key, value, expiration) VALUES (?, ?, ?);';
  db.execute(query, key, JSON.stringify(value), expires_in);
  db.close();
};

Cache.prototype.del = function(key) {
  var db = Titanium.Database.open('cache');
  db.execute('DELETE FROM cache WHERE key = ?', key);
  db.close();
  Ti.API.info('[CACHE] DEL: key[' + key + ']');
};

module.exports = new Cache;