How to enable Auto Scaling for Provisioned read capacity in DynamoDB from java script

Question

I am using AWS SDK for nodejs and creating a dynamodb table from the code. It all works fine but i need auto scaling to be enabled for provisioned read and write capacity. This is the code i am trying

var params = {
    TableName : "MyTable",
    KeySchema: [       
        { AttributeName: "Name", KeyType: "HASH"},  //Partition key
        { AttributeName: "time", KeyType: "RANGE" }  //Sort key
    ],
    AttributeDefinitions: [     

        { AttributeName: "Name", AttributeType: "S" },
        { AttributeName: "time", AttributeType: "N" }
    ],
    ProvisionedThroughput: {       
        ReadCapacityUnits: 5, 
        WriteCapacityUnits: 5
    }        
    ]
};

dynamodb.createTable(params, function(err, data) {
    if (err) {
        console.error("Unable to create table. Error JSON:", JSON.stringify(err, null, 2));
    } else {
        console.log("Created table. Table description JSON:", JSON.stringify(data, null, 2));
    }
});

This creates a table with read and write capacity as 5 but with auto scaling disabled. I have seen a java sample where auto scaling is being handled from code but nothing for java script. Any suggestions on how to enable auto scaling from NodeJS will be very helpful . Thanks

Answer 1

You can enable the auto-scaling through a separate ApplicationAutoScaling call.

Here a Lambda code sample of how to enable auto-scaling for write units:

const AWS = require("aws-sdk");
var applicationautoscaling = new AWS.ApplicationAutoScaling({
    apiVersion: '2016-02-06'
});

exports.handler = (event, context, callback) => {
    var params = {
        MaxCapacity: 10,
        MinCapacity: 2,
        ResourceId: "table/MyTable",
        RoleARN: "arn:aws:iam::111111111:role/lambda_s3_exec_role",
        ScalableDimension: "dynamodb:table:WriteCapacityUnits",
        ServiceNamespace: "dynamodb"
    };
    applicationautoscaling.registerScalableTarget(params, function(err, data) {
        if (err) console.log(err, err.stack); // an error occurred
        else console.log(data); // successful response
        callback(null, 'write capacity adjusted');
    });
};