DynamoDB to JSON

function mapper(data, setType) {

	let keys = Object.keys(data),
		ret = data.concat ? [] : {};

	console.log("keys", keys);

	while (keys.length) {
		let key = keys.shift(),
			obj = data[key];

		console.log("key", key, obj);

		if (setType) {
			switch(setType) {
				case "BB":
				case "SS":		ret[key] = obj;						break;
				case "NN":		ret[key] = parseFloat(obj);			break;
			}

		} else if (typeof obj === "object" && obj !== null) {
			let type = Object.keys(obj)[0];
			switch(type) {
				case "S":
				case "B":
				case "BOOL":	ret[key] = obj[type];				break;

				case "N":		ret[key] = parseFloat(obj[type]);	break;

				case "NULL":	ret[key] = null;					break;
				
				case "L":
				case "M":		ret[key] = mapper(obj[type]);		break;

				case "SS":
				case "NN":
				case "BB":		ret[key] = mapper(obj[type], type);	break;
			}
		}
	}

	return ret;
}

test.js

// taken from
// https://github.com/CascadeEnergy/dynamoDb-marshaler/blob/master/examples/example-unmarshal.js

var item = {
	name: {S: 'Will Vaughn'},
	age: {N: '30'},
	employed: {BOOL: true},
	relationshipStatus: {NULL: true},
	defaultReplies: {
		L: [
			{S: 'No.'},
			{N: '42'}
		]
	},
	appearance: {
		M: {
			height: {N: '183'},
			weight: {N: '79'},
			eyeColor: {S: 'brown'},
			ethnicity: {
				M: {
					whiteAmerican: {BOOL: true},
					nativeAmerican: {BOOL: false},
					asianAmerican: {BOOL: false},
					africanAmerican: {BOOL: false},
					nativeHawaiianOrPacificIslander: {BOOL: false},
					someOtherRace: {BOOL: false}
				}
			}
		}
	},
	favoriteFoods: {
		SS: [
			'burritos',
			'fried chicken',
			'pad kee mao'
		]
	},
	luckyNumbers: {
		NN: ['42', '98', '777']
	},
	empty: {
		L: []
	},
	duplicateList: {
		L: [
			{
				S: 'foo'
			},
			{
				S: 'bar'
			},
			{
				S: 'foo'
			}
		]
	}
};
mapper(item);

//{
//  "name": "Will Vaughn",
//  "age": 30,
//  "employed": true,
//  "relationshipStatus": null,
//  "defaultReplies": ["No.", 42],
//  "appearance": {
//    "height": 183,
//    "weight": 79,
//    "eyeColor": "brown",
//    "ethnicity": {
//      "whiteAmerican": true,
//      "nativeAmerican": false,
//      "asianAmerican": false,
//      "africanAmerican": false,
//      "nativeHawaiianOrPacificIslander": false,
//      "someOtherRace": false
//    }
//  },
//  "favoriteFoods": ["burritos", "fried chicken", "pad kee mao"],
//  "luckyNumbers": [42, 98, 777],
//  "empty": [],
//  "duplicateList": ["foo", "bar", "foo"]
//}