Node.js getitem from dynamoDB and pass variable - aws-lambda

Question

I'm working on some labmda code in Node.js, and I want to pass an item gotten from DynamoDB with getitem to some code. Here's what I have:
const Alexa = require('ask-sdk');
const AWS = require ('aws-sdk');
AWS.config.update({region: 'us-east-1'});
//replace dynamo later with dynamo
dynamodb = new AWS.DynamoDB();
//const appId = 'REPLACE WITH YOUR SKILL APPLICATION ID';
const date = new Date(Date.now()).toString();
const date2 = date.substring(0,16);
const time = date.substring(16,24);
const LaunchRequestHandler = {
canHandle(handlerInput) {
//first we assign the requestEnvelope request to the request variable
const request = handlerInput.requestEnvelope.request;
//conditions to determine the requests this handler can handle
//now using the request variable, we return true if it equals the one we want
//in this case LaunchRequest
return request.type === 'LaunchRequest'
},
handle(handlerInput) {
//execution logic for the handler
// ie What exactly do we do
const speechOutput =
"Welcome to Track it, you can tell me who you lent things to, \
or where you put an item. For example I lent the saw to Mike, or I put the saw in the workshop."
return handlerInput.responseBuilder
.speak(speechOutput)
.getResponse();
}
}
const GaveIntentHandler = {
canHandle(handlerInput) {
return handlerInput.requestEnvelope.request.type === 'IntentRequest'
&& handlerInput.requestEnvelope.request.intent.name === 'GaveIntent';
},
handle(handlerInput,event) {
// setting variable attributes to handle things like counters
const attributes = handlerInput.attributesManager.getSessionAttributes();
// personName and itemName are pulling the slots information from the intent
const personName = handlerInput.requestEnvelope.request.intent.slots.lenderPerson.value;
const itemName = handlerInput.requestEnvelope.request.intent.slots.storedObject.value;
const currentUser = handlerInput.requestEnvelope.session.user.userId;
//begin DB code
var params = {
TableName: 'TrackItDB',
Item: {
'userID' : {S: currentUser},
'storedObject' : {S: itemName},
'lenderPerson' : {S: personName},
'objectStatus' : {S: 'lent'},
'transactionDate': {S: date},
},
ConditionExpression: 'attribute_not_exists(storedObject)'
};
console.log(params);
// putItem in database only if it doesn't already exist
dynamodb.putItem(params, function(err, data) {
if (err) {
console.log("Error", err);
console.log("That item already exists");
} else {
console.log("Success", data);
}
});
console.log(personName);
console.log(itemName);
console.log(currentUser);
const speechOutput = 'You Gave ' + personName + ' the ' + itemName;
return handlerInput.responseBuilder
.speak(speechOutput)
.withSimpleCard('Track It', speechOutput)
.getResponse();
}
};
const PutIntentHandler = {
canHandle(handlerInput) {
return handlerInput.requestEnvelope.request.type === 'IntentRequest'
&& handlerInput.requestEnvelope.request.intent.name === 'PutIntent';
},
handle(handlerInput) {
const itemName = handlerInput.requestEnvelope.request.intent.slots.storedObject.value;
const LocationName = handlerInput.requestEnvelope.request.intent.slots.storageLocation.value;
const currentUser = handlerInput.requestEnvelope.session.user.userId;
//begin DB code
var params = {
TableName: 'TrackItDB',
Item: {
'userID' : {S: currentUser},
'storedObject' : {S: itemName},
'lenderPerson' : {S: LocationName},
'objectStatus' : {S: 'stored'},
'transactionDate': {S: date},
},
ConditionExpression: 'attribute_not_exists(storedObject)'
};
dynamodb.putItem(params, function(err, data) {
if (err) {
console.log("Error", err);
console.log("That item already exists");
}
else {
console.log("Success", data);
}
});
//end DB code
const speechOutput = 'You put the ' + itemName + ' in the ' + LocationName;
return handlerInput.responseBuilder
.speak(speechOutput)
.withSimpleCard('Hello World', speechOutput)
.getResponse();
}
};
const WhereIsIntentHandler = {
canHandle(handlerInput) {
return handlerInput.requestEnvelope.request.type === 'IntentRequest'
&& handlerInput.requestEnvelope.request.intent.name === 'WhereIsIntent';
},
handle(handlerInput) {
const itemName = handlerInput.requestEnvelope.request.intent.slots.storedObject.value;
const currentUser = handlerInput.requestEnvelope.session.user.userId;
// begin DB query
var params = {
Key: {
"userID": {
S: currentUser
},
"storedObject": {
S: itemName
}
},
TableName: "TrackItDB"
};
// End DB Query
dynamodb.getItem(params, function(err, data) {
if (err) {
console.log("Error", err);
}// an error occurred
else {
console.log("Success", data); // successful response
const LocationName = data.Item.lenderPerson.S;
const speechOutput = 'Your ' + itemName + ' is in the ' + LocationName;
return handlerInput.responseBuilder
.speak(speechOutput)
.withSimpleCard('Hello World', speechOutput)
.getResponse();
}
});
}
};
const HelpIntentHandler = {
canHandle(handlerInput) {
return handlerInput.requestEnvelope.request.type === 'IntentRequest'
&& handlerInput.requestEnvelope.request.intent.name === 'AMAZON.HelpIntent';
},
handle(handlerInput) {
const speechOutput = 'Welcome to Track it, you can tell me who you lent things to, or where you put an item. For example I lent the saw to Mike, or I put the saw in the workshop.';
return handlerInput.responseBuilder
.speak(speechOutput)
.reprompt(speechOutput)
.withSimpleCard('Hello World', speechOutput)
.getResponse();
}
};
const CancelAndStopIntentHandler = {
canHandle(handlerInput) {
return handlerInput.requestEnvelope.request.type === 'IntentRequest'
&& (handlerInput.requestEnvelope.request.intent.name === 'AMAZON.CancelIntent'
|| handlerInput.requestEnvelope.request.intent.name === 'AMAZON.StopIntent');
},
handle(handlerInput) {
const speechOutput = 'Goodbye!';
return handlerInput.responseBuilder
.speak(speechOutput)
.withSimpleCard('Hello World', speechOutput)
.getResponse();
}
};
const SessionEndedRequestHandler = {
canHandle(handlerInput) {
return handlerInput.requestEnvelope.request.type === 'SessionEndedRequest';
},
handle(handlerInput) {
//any cleanup logic goes here
return handlerInput.responseBuilder.getResponse();
}
};
const skillBuilder = Alexa.SkillBuilders.custom();
exports.handler = skillBuilder
.addRequestHandlers(
LaunchRequestHandler,
GaveIntentHandler,
PutIntentHandler,
WhereIsIntentHandler,
HelpIntentHandler,
SessionEndedRequestHandler,
CancelAndStopIntentHandler
)
.lambda()
I'm trying to pass the "itemName and LocationName to the const speechOutput variable so I can have Alexa speak it for me.
It will work in the console log, but not later outside the getitem function. FYI, I know I shouldn't have the const speechOutput twice, and it isn't like that in my code; I just put it there to show what I'm trying to do.

Answer 1

You need to move the responseBuilder code snippet within the getItem function' else part.
Do not declare the const speechOutput twice.
handle(handlerInput) {
const itemName =
handlerInput.requestEnvelope.request.intent.slots.storedObject.value;
const currentUser =
handlerInput.requestEnvelope.session.user.userId;
// Begin database query
var params = {
Key: {
"userID": {
S: currentUser
},
"storedObject": {
S: itemName
}
},
TableName: "TrackItDB"
};
// End DB Query
//const speechOutput = 'test'
dynamodb.getItem(params, function(err, data) {
if (err) {
console.log("Error", err);
} // An error occurred
else {
console.log("Success", data); // Successful
// response
const LocationName = data.Item.lenderPerson.S;
const speechOutput = 'Your ' + itemName + ' is in the ' +
LocationName;
// Speak the output
return handlerInput.responseBuilder
.speak(speechOutput)
.withSimpleCard('Hello, World!', speechOutput)
.getResponse();
console.log(speechOutput);
}
});
//const speechOutput = 'Your ' + itemName + ' is in the ' +
LocationName;
}