Lambda keeps giving the same errors - node.js

Question

I've been trying to figure out an issue with an amazon lex chatbot I've been building all day. The node.js lambda keeps giving the same errors and for the life of me I can't figure out why. The chatbot is called BestiaryProject, the Intent is MonsterSearch, and the two slots are monsterType and monsterName.
The error I get is as follows:
"a9fba2d2-ec22-4092-b332-53ae16acb345 ERROR Invoke Error {"errorType":"Error","errorMessage":"Intent with name undefined not supported","stack":["Error: Intent with name undefined not supported"," at dispatch (/var/task/index.js:168:11)"," at Runtime.exports.handler (/var/task/index.js:189:9)"," at Runtime.handleOnce (file:///var/runtime/index.mjs:548:29)"]}"
here is the code:
function elicitSlot(sessionAttributes, intentName, slots, slotToElicit, message) {
return {
sessionAttributes,
dialogAction: {
type: 'ElicitSlot',
intentName,
slots,
slotToElicit,
message,
},
};
}
function close(sessionAttributes, fulfillmentState, message) {
return {
sessionAttributes,
dialogAction: {
type: 'Close',
fulfillmentState,
message,
},
};
}
function delegate(sessionAttributes, slots) {
return {
sessionAttributes,
dialogAction: {
type: 'Delegate',
slots,
},
};
}
// ---------------- Helper Functions --------------------------------------------------
function buildValidationResult(isValid, violatedSlot, messageContent) {
if (messageContent == null) {
return {
isValid,
violatedSlot,
};
}
return {
isValid,
violatedSlot,
message: { contentType: 'PlainText', content: messageContent },
};
}
let page = 0;
//function to validate user inputs and return page number
function validateMonsters(monsterType, monsterName, time) {
const monsterTypes = ['dragon', 'fiend', 'celestial', 'giant', 'magical beast', 'fey', 'undead', 'elemental'];
if (monsterType && monsterTypes.indexOf(monsterType) === -1) {
return buildValidationResult(false, 'monsterType', `I do not know what ${monsterType} is, would you like to try a different one?`);
}
const monsterNames = ['vampire', 'troll', 'fire giant', 'wyvern', 'true dragon', 'angel', 'azata', 'chimera', 'manticore', 'unicorn', 'dryad', 'ghoul', 'fire elemental', 'water elemental', 'balor', 'succubus'];
if (monsterName && monsterNames.indexOf(monsterName) === -1) {
return buildValidationResult(false, 'monsterName', `I've never heard of ${monsterName}, would you like to try a different one?`);
}
const pages = [9, 23, 44, 58, 68, 90, 116, 124, 125, 146, 148, 199, 268, 269, 270, 282];
if (monsterName == 'angel') {
page = pages[0];
}
if (monsterName == 'azata') {
page = pages[1];
}
if (monsterName == 'chimera') {
page = pages[2];
}
if (monsterName == 'balor') {
page = pages[3];
}
if (monsterName == 'succubus') {
page = pages[4];
}
if (monsterName == 'true dragon') {
page = pages[5];
}
if (monsterName == 'dryad') {
page = pages[6];
}
if (monsterName == 'fire elemental') {
page = pages[7];
}
if (monsterName == 'water elemental') {
page = pages[8];
}
if (monsterName == 'ghoul') {
page = pages[9];
}
if (monsterName == 'fire giant') {
page = pages[10];
}
if (monsterName == 'manticore') {
page = pages[11];
}
if (monsterName == 'troll') {
page = pages[12];
}
if (monsterName == 'unicorn') {
page = pages[13];
}
if (monsterName == 'vampire') {
page = pages[14];
}
if (monsterName == 'wyvern') {
page = pages[15];
}
return buildValidationResult(true, null, null);
}
// --------------- Functions that control the bot's behavior -----------------------
/**
* Performs dialog management and fulfillment for finding your monster.
*
* Beyond fulfillment, the implementation of this intent demonstrates the use of the elicitSlot dialog action
* in slot validation and re-prompting.
*
*/
function searchMonsters(intentRequest, callback) {
const monsterType = intentRequest.currentIntent.slots.monsterType;
const monsterName = intentRequest.currentIntent.slots.monsterName;
const source = intentRequest.invocationSource;
if (source === 'DialogCodeHook') {
// Perform basic validation on the supplied input slots. Use the elicitSlot dialog action to re-prompt for the first violation detected.
const slots = intentRequest.currentIntent.slots;
const validationResult = validateMonsters(monsterType, monsterName, page);
if (!validationResult.isValid) {
slots[`${validationResult.violatedSlot}`] = null;
callback(elicitSlot(intentRequest.sessionAttributes, intentRequest.currentIntent.name, slots, validationResult.violatedSlot, validationResult.message));
return;
}
}
// give user info on the monster, and rely on the goodbye message of the bot to define the message to the end user. In a real bot, this would likely involve a call to a backend service.
callback(close(intentRequest.sessionAttributes, 'Fulfilled',
{ contentType: 'PlainText', content: `Thanks, the monster ${monsterName} of type ${monsterType} can be found on page ${page}` }));
}
// --------------- Intents -----------------------
/**
* Called when the user specifies an intent for this skill.
*/
function dispatch(intentRequest, callback) {
console.log(`dispatch userId=${intentRequest.userId}, intentName=${intentRequest.currentIntent.name}`);
const intentName = intentRequest.currentIntent.name;
// Dispatch to your skill's intent handlers
if (intentName === 'MonsterSearch') {
return searchMonsters(intentRequest, callback);
}
throw new Error(`Intent with name ${intentName} not supported`);
}
// --------------- Main handler -----------------------
// Route the incoming request based on intent.
// The JSON body of the request is provided in the event slot.
exports.handler = (event, context, callback) => {
try {
console.log(`event.bot.name=${event.bot.name}`);
/**
* Uncomment this if statement and populate with your Lex bot name and / or version as
* a sanity check to prevent invoking this Lambda function from an undesired Lex bot or
* bot version.
*/
if (event.bot.name !== 'BestiaryProject') {
callback('Invalid Bot Name');
}
dispatch(event, (response) => callback(null, response));
} catch (err) {
callback(err);
}
};```

Answer 1

Quite simply what the error is telling you is that intentRequest.currentIntent.name is not resulting in a valid value; in fact you're getting back a null.
Try logging the entire intentRequest object at the start of your dispatch method to view the data that's passed through to your method and ensure you're looking in the right place for the intent name.