I am new to dynamoDB and node.js I have written a code where it will make a query to the database (dynamodb) and look for an element which is entered by the user in the database. I am able to verify that but when the user tries with some other number which is not present in the database I am getting a null value.
My table name is "DevReferenceNumber" and only one column which is primary key "referencenumber".
'use strict';
var AWS = require('aws-sdk');
var docClient = new AWS.DynamoDB.DocumentClient({ region : 'us-east-1'});
function close(sessionAttributes, fulfillmentState, message) {
return {
sessionAttributes,
dialogAction: {
type: 'Close',
fulfillmentState,
message,
},
};
}
exports.handler = (event, context, callback) => {
try{
console.log(`event.bot.name=${event.bot.name}`);
if(event.bot.name != 'getCustomerReferenceNumber'){
callback('Invalid Bot Name');
}
dispatch(event, (response) => {
callback(null, response)
});
}catch(err){
callback("Error is occured while querying");
}
};
function dispatch(intentRequest, callback){
console.log(`dispatch UserID => ${intentRequest.userId}, intentName => ${intentRequest.currentIntent.name}`);
const intentName = intentRequest.currentIntent.name;
if(intentName === "checkReferenceNumber"){
return referenceNumber(intentRequest, callback);
}
}
function referenceNumber(intentRequest, callback){
const enteredReferenceNumber = intentRequest.currentIntent.slots.ReferenceNumber;
const sessionAttributes = intentRequest.sessionAttributes;
console.log("User has entered reference number is --> " + enteredReferenceNumber);
var params = {
TableName : "DevReferenceNumber",
KeyConditionExpression: "#refer = :ref",
ProjectionExpression : "#refer",
ExpressionAttributeNames: {
"#refer" : "referencenumber"
},
ExpressionAttributeValues:{
":ref": parseInt(enteredReferenceNumber)
}
};
docClient.query(params, function(err, data){
if(err){
callback(close(sessionAttributes, 'Fulfilled', {
contentType: 'PlainText',
content : 'Developer reference number is not matched with data from database'}));
}
else {
data.Items.forEach(function (item){
console.log("User matched data is ==> " + item.referencenumber);
callback(close(sessionAttributes, 'Fulfilled', {
contentType: 'PlainText',
content : 'Developer reference number is matched with data from database'}));
});
}
});
}
