AWS KMS code to decrypt the encrypted connection string

mongodb-atlas-lambda-step2.js

const kms = new AWS.KMS();
        kms.decrypt({ CiphertextBlob: new Buffer(uri, 'base64') }, (err, data) => {
            if (err) {
                console.log('Decrypt error:', err);
                return callback(err);
            }
            atlas_connection_uri = data.Plaintext.toString('ascii');
            processEvent(event, context, callback);
        });