Run the following in a terminal in your source code directory:
This will install all the Node.js packages that you need for the tutorial. The three packages are aws-sdk, tmi.js and yargs. The AWS SDK will give you programmatic access to Amazon Comprehend and Amazon CloudWatch. The tmi.js package provides an easy way to interact with Twitch chat. You don’t need to authenticate to listen for messages from chat, which makes monitoring a little easier. You can also use this package to create bots that listen for commands and respond, however in that case you would need to authenticate. The yargs package makes it easier to parse command-line arguments, which will be useful for parameterizing the main script.