AWS Lambda in TypeScript

Install

1. Dependencies

npm install

2. Download ngrok in the root folder

Run project

1. Open a console

npm run ngrok

Copy the https link and go to Alexa Console, under Endpoint section, select HTTPS and paste the link in Default Region input field. From the below dropdown choose My development endpoint is a sub-domain of a domain that has a wildcard certificate from a certificate authority. Every time when you run the ngrok, you need to update the endpoint url. [1]

2. Open another console

npm start

Deploy

Use npm to install ASK CLI. If you already have ASK CLI installed and want to update to the latest version, install it in the same way as a new user.

$ npm install -g ask-cli

After you install ask-cli, initialize ASK CLI:

$ ask init

You will be prompted to name your profile (default by default), choose the AWS profile to use, and to log in to your Amazon developer account. Once the initialization is complete, you can use ASK CLI to manage your skill.

If you choose to create a new one, first go in AWS IAM, create an user or choose an existing one and create an access key.

Press Add permission button > Attach existing policy > Create policy > open JSON format and paste the following code

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "iam:CreateRole",
                "iam:GetRole",
                "iam:AttachRolePolicy",
                "iam:PassRole"
            ],
            "Resource": "arn:aws:iam::*:role/ask-*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "lambda:AddPermission",
                "lambda:CreateFunction",
                "lambda:GetFunction",
                "lambda:UpdateFunctionCode",
                "lambda:ListFunctions"
            ],
            "Resource": "arn:aws:lambda:*:*:function:ask-*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "logs:FilterLogEvents",
                "logs:getLogEvents",
                "logs:describeLogStreams"
            ],
            "Resource": "arn:aws:logs:*:*:log-group:/aws/lambda/ask-*"
        }
    ]
}

Refference here

Last step, go to ./ask/config and place you skill_id and your lambda arn.

In order to deploy run:

$ ask deploy

Developer tasks

Frequently used npm scripts:

Script name	Description
start	Runs the service locally, so you can call your API endpoints on http://localhost.
ngrok	Runs the ngrok service locally, so you can use the https endpoint in Alexa skill: https://XXXXX.ngrok.io.
build	Clean the build and start a new process to build again the files
clean	Clean the build
deploy	Build the project and then deploy to aws lambda
sync:model	Sync the model from Alexa Skill Console with local model from models folder

Resources

1. https://medium.com/@cnadeau_/allow-alexa-to-run-your-locally-hosted-skill-1786e3ca7a1b
2. https://github.com/balassy/aws-lambda-typescript
3. https://ask-sdk-for-nodejs.readthedocs.io/en/latest/Developing-Your-First-Skill.html
4. https://ngrok.com/
5. https://github.com/alexa/alexa-skills-kit-sdk-for-nodejs
6. https://developer.amazon.com/docs/smapi/ask-cli-command-reference.html
7. https://developer.amazon.com/docs/smapi/quick-start-alexa-skills-kit-command-line-interface.html