How do I initiate a conversation with AWS LEX from node js? - node.js

Question

My context is this: I am attempting to build a chat bot into my Mozilla Hubs client, which is a node js / React project. I have a lex bot created on AWS, and I have installed the client-lex-runtime-v2 package and can import it successfully, but I have no idea how to set up a StartConversationCommand, give it credentials, etc. Most of the javascript examples seem to go the other way, where Lex calls a lambda function after processing a request, but I have user input in my app and I need to send it to Lex, and then deliver the resulting text back to the user inside my application.
This seems like very basic Lex usage - if anyone could point me to a code example I would be most grateful.

Answer 1

John,
You need to make use of the LexRuntimeV2Client in the SDK as demonstrated here.
From the linked documentation, the below is how you import and instantiate a new client:
import { LexRuntimeV2Client, DeleteSessionCommand } from "#aws-sdk/client-lex-runtime-v2";
const client = new LexRuntimeV2Client({ region: "REGION" });
Once configured with your respective AWS environment details, credentials etc you will be able to invoke your Lex bot (again, from the linked documentation):
try {
const data = await client.send(command);
// process data.
} catch (error) {
// error handling.
} finally {
// finally.
}
Take a look at this sample repo on GitHub as well: aws-lex-web-ui

Answer 2

So for anyone else stuck where I was, I cannot say this is the right way to do it, because I never did get it working, but the closest I got to at least forming up my credentials and trying to make a connection was this:
const client = new LexRuntimeV2Client({
region: "us-east-1",
credentials: new AWS.Credentials({
accessKeyId: "my_IAM_access_key_id",
secretAccessKey: "my_secret_access_key"
})
});
const lexparams = {
"botAliasId": "my alias_id",
"botId": "bot_id_from_lex",
"localeId": "en_US",
"inputText": "hello, this is a test sample",
"sessionId": "some_session_id"
};
let cmd = new StartConversationCommand(lexparams);
try {
const data = await client.send(cmd);
console.log("Success. Response is: ", data.message);
} catch (err) {
console.log("Error responding to message. ", err);
}
As said, buyer beware, and best of luck out there! I hope this might help somebody in some slight way. We taking a momentary break on this problem until a member of our team with better aws fu can take a look at it. :-)

Answer 3

This is working for me:
var AWS = require('aws-sdk');
const { LexRuntimeV2 } = require("#aws-sdk/client-lex-runtime-v2");
const lexruntime = new LexRuntimeV2({
region: "us-west-2", // Set your Bot Region
credentials: new AWS.Credentials({
accessKeyId: "***", // Add your access IAM accessKeyId
secretAccessKey: "***" // Add your access IAM secretAccessKey
})
});
const lexparams = {
"botAliasId": "HG****", // Enter the botAliasId
"botId": "HG***", // Enter the botId
"localeId": "en_US",
"text": "Book Car",
"sessionId": "some_session_id"
};
lexruntime.recognizeText(lexparams, function(err, data) {
if (err) console.log(err, err.stack); // an error occurred
else console.log(data); // successful response
});