An example of make a dynamic object update using dinamodb and nodejs.

dynamo_dynamic_update.js

const AWS = require('aws-sdk');

//Define aws region
AWS.config.update({
	region:'us-east-1'
});

const TABLE = 'dc_test';

//Get aws dynamo client instance.
const docClient = new AWS.DynamoDB.DocumentClient();

//Register data in dynamodb table.
const update = (params)=> docClient.update(params).promise();

//Make the query with partial values.
const partialUpdate = (table, key, object)=>{

	//Create params.
	let query = {
	  TableName: table,
	  Key: key,
	  UpdateExpression: '',
	  ExpressionAttributeValues: {}
	};

	//Get object keys.
	const keys = Object.keys(client);

	//Fill expresion attribute values.
	let expAttrib={};
	keys.forEach(e=>expAttrib[`:${e}`]=client[e]);

	//Fill update expression.
	let updExpression='';
	keys.forEach((val,i)=>{
		if (i<keys.length-1)
			updExpression=updExpression+`${val}=:${val},`;
		else
			updExpression=updExpression+`${val}=:${val}`;
	});

	//Complete values.
	query.ExpressionAttributeValues=expAttrib;
	query.UpdateExpression=`SET ${updExpression}`;

	return query;

}

//Lambda handler.
const run = async (object) => {

	//Make the dynamic query by the object keys.
	const query = partialUpdate('dc_test', {'user_id':'1234'}, object);

	//Run update.
  const result = await update(query);

  console.log('query',query);
  console.log('result',result);

  return result;

};

const client = {
	email:'damian.cipolat@gmail.com',
	google:{
		avatar:"www.damian.com",
		email:"damian.cipolat@gmail.com",
		name:"sssssssssssss"
	},
	document:{
		firstName:'Damian',
		lastName:'Cipolat',
		number:'332955215',
		address:'Opa opa',
		gender:'M',
		birthdate:'1987-10-06',
		country:'ARGENTINA',
		nationality:'ARGENTINA',
		expiration:'2987-10-06',
		fiscalNumber:'2033295515'
	},
	legal:{
		fatca:false,
		ddjj:false,
		pep:false
	},
	phone:{
		country:"+54",
		number:"1166587382",
		validatedAt:"2019-01-'01"
	},
	signedTyc:{
		date:"01/01/01",
		version:"1.0"
	},
	account:{
		opRerenceId:"123124343243243232324"
	}
};

run(client);