Dynamo db json re mapper

dynamodb-json-mapper.js

/**
MIT License

Copyright (c) 2016 Igor Ivanovic

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.
**/
/**

 * Dynamodb types
 S – String
 N – Number
 B – Binary
 BOOL – Boolean
 NULL – Null
 M – Map
 L – List
 SS – String Set
 NN – Number Set
 BB – Binary Set
 
 This function remapps dynamodb dsl json to normal json object

 FROM:
 {
   "spike_id": {
     "S": "57"
   },
   "Day": {
     "S": "Monday"
   }
 }
 TO:
 {
   "spike_id": "57",
   "Day": "Monday"
 }

 */



function mapper(data) {

    let S = "S";
    let SS = "SS";
    let NN = "NN";
    let NS = "NS";
    let BS = "BS";
    let BB = "BB";
    let N = "N";
    let BOOL = "BOOL";
    let NULL = "NULL";
    let M = "M";
    let L = "L";

    if (isObject(data)) {
        let keys = Object.keys(data);
        while (keys.length) {
            let key = keys.shift();
            let types = data[key];

            if (isObject(types) && types.hasOwnProperty(S)) {
                data[key] = types[S];
            } else if (isObject(types) && types.hasOwnProperty(N)) {
                data[key] = parseFloat(types[N]);
            } else if (isObject(types) && types.hasOwnProperty(BOOL)) {
                data[key] = types[BOOL];
            } else if (isObject(types) && types.hasOwnProperty(NULL)) {
                data[key] = null;
            } else if (isObject(types) && types.hasOwnProperty(M)) {
                data[key] = mapper(types[M]);
            } else if (isObject(types) && types.hasOwnProperty(L)) {
                data[key] = mapper(types[L]);
            } else if (isObject(types) && types.hasOwnProperty(SS)) {
                data[key] = types[SS];
            } else if (isObject(types) && types.hasOwnProperty(NN)) {
                data[key] = types[NN];
            } else if (isObject(types) && types.hasOwnProperty(BB)) {
                data[key] = types[BB];
            } else if (isObject(types) && types.hasOwnProperty(NS)) {
                data[key] = types[NS];
            } else if (isObject(types) && types.hasOwnProperty(BS)) {
                data[key] = types[BS];
            }
        }
    }


    return data;

    function isObject(value) {
        return typeof value === "object" && value !== null;
    }
}

Hi @igorzg

can you check why this example is not working as expected?

` var source2 = '{"spike_id": {"S": "57"}, "Day": {"S": "Monday"} }'

    function mapper(data) {

    let S = "S";
            let N = "N";
            let B = "B";
            let BOOL = "BOOL";
            let NULL = "NULL";
            let M = "M";
            let L = "L";
            let keys = Object.keys(data);
            while (keys.length) {
    let key = keys.shift();
            let types = data[key];
            if (isObject(types) && types.hasOwnProperty(S)) {
    data[key] = types[S];
    } else if (isObject(types) && types.hasOwnProperty(B)) {
    data[key] = types[B];
    } else if (isObject(types) && types.hasOwnProperty(N)) {
    data[key] = parseFloat(types[N]);
    } else if (isObject(types) && types.hasOwnProperty(BOOL)) {
    data[key] = types[BOOL];
    } else if (isObject(types) && types.hasOwnProperty(NULL)) {
    data[key] = null;
    } else if (isObject(types) && types.hasOwnProperty(M)) {
    data[key] = mapper(types[M]);
    } else if (isObject(types) && types.hasOwnProperty(L)) {
    data[key] = mapper(types[L]);
    }
    }

    return data;
            function isObject(value) {
            return typeof value === "object" && value !== null;
            }
    }

var result = (mapper(source2));
console.log(result);`

Will print {"spike_id": {"S": "57"}, "Day": {"S": "Monday"} } which seems to be wrong.
Thank you!

Hi @dwaldmannDE

You have to convert your json string to object.

 var source2 = JSON.parse('{"spike_id": {"S": "57"}, "Day": {"S": "Monday"} }');
mapper(source2)

Will give you expected result!

What is the license for this? I'd love to grab and go since dynamodb streams sends data in the inconvenient format, but I want to make sure you're ok with it first.

@kestess its MIT