A mock dynamo client that helps unit testing.

mockDynamo.js

var DATABASE = {};
/**
 * Start awk-sdk mock
 */
exports.getItem = function(params, cb) {
 
  if (params.AttributesToGet) {
    var ret = {
      Item: {}
    };
 
    if (DATABASE[params.Key.HashKeyElement.S]) {
      for (var a in params.AttributesToGet) {
        var p = params.AttributesToGet[a];
        ret.Item[p] = DATABASE[params.Key.HashKeyElement.S][p];  
      }
 
      cb(null, ret);
    }
    else {
        return cb(null, null);      
    }
  }
  else {
    cb(null, { Item: DATABASE[params.Key.HashKeyElement.S]});  
  }
};
 
exports.putItem = function(params, cb) {
  DATABASE[params.Item.isu.S] = params.Item;
  cb(null, {});
};
 
exports.deleteItem = function(params, cb) {
  delete DATABASE[params.Key.HashKeyElement.S];
  cb(null, {});
};
 
exports.updateItem = function(params, cb) {
  var isu = params.Key.HashKeyElement.S;
  for (var i in params.AttributeUpdates) {
    if (params.AttributeUpdates[i].Action === "ADD") {
      // Add to existing value
      if (!DATABASE[isu]) {
        DATABASE[isu] = {
          isu: { S: isu }
        };
      }
      var incBy = parseInt(params.AttributeUpdates[i].Value.N, 10);
      if (!DATABASE[isu][i]) {
        DATABASE[isu][i] = { "N" : "0" };
      }
      var old = parseInt(DATABASE[isu][i].N, 10);
      DATABASE[isu][i] = { "N": (old + incBy).toString()};
    }
    else if (params.AttributeUpdates[i].Action === "PUT") {
      // Overwrite
      if (!DATABASE[isu]) {
        DATABASE[isu] = {
          isu: { S: isu }
        };
      }
      DATABASE[isu][i] = params.AttributeUpdates[i].Value;
    }
  }
  cb(null, {ConsumedCapacityUnits: 1});
};
 
/**
 * Start jed dynamo library mock
 */
exports.get = function get(table, obj) {
 
};
 
exports.DATABASE = DATABASE;