MoveDynamoRecords

const AWS = require("aws-sdk")
const _ = require("lodash")
const dynamo = new AWS.DynamoDB.DocumentClient({
    apiVersion: "2012-08-10",
    region: "eu-west-1"
})

const BATCH_SIZE = 25;
const sourceTable = "<put-value-here>";
const destinationTable = "<put-value-here>";

loadItems({TableName: sourceTable, Limit: 100, })
    .then(
        result => console.log("Done", result),
        err => console.error("Loading items failed", err)
        )


function processItems(res) {
    const batches = _.chunk(res.Items, BATCH_SIZE);
    return Promise.all(batches
        .map(bachItems => {
            console.log("Persisting batch", bachItems)
            return dynamo.batchWrite({
                RequestItems: {
                    [destinationTable]: bachItems
                        .map(dynamoItem => ({
                            PutRequest: {
                                Item: dynamoItem
                            }
                        }))
                }
            }).promise()
        })
    )
}

async function loadItems(params) {
    let results = []
    console.log("Scanning", params)
    const scanResult = await dynamo.scan(params, (err, data) => {
        if (err) {
            console.error("Scanning failed", JSON.stringify(err, null, 2))
        } else {
            results = data.Items
        }
    }).promise();

    await processItems(scanResult)

    if (typeof scanResult.LastEvaluatedKey != "undefined") {
        params.ExclusiveStartKey = scanResult.LastEvaluatedKey
        return loadItems(params)
    }
    return results
}