Why?

Library is extenstion for cache-manager. DynamoDB is not typical usecase for caches, but can be used as backing engine to store your cache or configuration.

Usage

Regular usecase for that lib is to chain DynamoDB with memory cache. It will give you persistance layer + fast access. For example it can be used to load your application configuration dynamically from the DynamoDB. Here is example.

var Promise = require('bluebird');
var cacheManager = require('cache-manager');
var DynamoDB = require('dynamodb-cache-manager');

var memoryCache = cacheManager.caching({
  store: 'memory', 
  max: 100, 
  ttl: 10,
});

var dynamoDBCache = cacheManager.caching({
  store: DynamoDB, 
  tableName: 'tableName',
  keyField: 'key'.
  valField: 'cache',
  connection: {
    region: 'us-east-1'
  }
});

var memory = Promise.promisifyAll(memoryCache);
var dynamo = Promise.promisifyAll(dynamoDbCache);

dynamoDbCache.get('12345', (err, res) => {
  console.log(res);
});

var pollCache = () => {
  return memory.getAsync(key)
    .then(res => {
      if (res)  return res;
      else return dynamo.getAsync(key)
                  .then(res => memory.set(key, res))
                  .then(()  => memory.get(key));
    })
    .then((res) => {      
      console.log("Cache data: " + res);
      setTimeout(fn, 1000)
    })
    .catch(err => {
      console.error(err);
    });
}

pollCache();

Above example will poll DynamoDB every 10 seconds and store result in memory, so every time you access it it won't go to the database.

TODO

• finish/fix docs
• figure our right wasy to utilize cache-mananger multicache