serverless-nodejs-aws-demo

Pre-requisites:

• NodeJs
• Serverless Framework CLI
• AWS CLI
• Active AWS account with ApiGateway and Dynamo db access

$node -v

Install serverless framework:
$npm install serverless -g 

$serverless -v  (or) sls -v

$aws --version

$aws configure 
AWS Access Key ID [None]: <<Input here>>
AWS Secret Access Key [None]: <<Input here>>
Default region name [None]:
Default output format [None]:

AWS IAM and Policies::

Please follow these steps while creating the AWS IAM User.

• Go to the Users section under Identity and Access Management (IAM) services in AWS management console.
• Click Add User
• Enter a valid user name. Under Select AWS access type check the box for Programmatic access.
• Select Attach existing policies directly under Set permissions on the Add User screen.
• Attach the below listed policies to the IAM User.
• Standard AWS Managed Policies that you need to attach to your user.

AmazonDynamoDBFullAccess
AmazonAPIGatewayAdministrator
AWSLambdaFullAccess

• Hit Next:Tags. Skip to Next:Review
• Review the User permissions and policies attached. Hit Create user.
• From the confirmation screen please download and save the ACCESS_KEY_ID and SECRET_ACCESS_KEY at a secure location.

To run the project locally, you will need the following secrets from your AWS IAM User.

• ACCESS_KEY_ID
• SECRET_ACCESS_KEY

Using serverless to setup aws credentials on your machine

• Grab the ACCESS_KEY_ID and SECRET_ACCESS_KEY for the above created IAM User and replace it in the below command respectively.

$ node_modules/.bin/serverless config credentials --provider aws --key <ACCESS_KEY_ID> --secret <SECRET_ACCESS_KEY>

This will create ~/.aws/credentials in your computer. serverless will use this credentials to deploy to your account

What is serverless framework??

Serverless framework application model:

• Functions: which executes some code in response to some events.

• Events: Like HttpRequest, a schedule timer event or infrastructure provider event like aws s3 fileupload event

    In AWS, you can trigger functions with the events from API Gateway, s3, CloudWatch, DynamoDb
  

• Resources: Infrastructure that your application depends on ex: dynamodb table, aws s3 bucket etc.

• Serverless Services: A service is like a project. It's where you define your AWS Lambda functions, the events that trigger them and any AWS Infrastructure resources they require, all in a file called serverless.yml. A fullblown application can have many services.

What is AWS ApiGateway?

Amazon API Gateway is an AWS service for creating, publishing, maintaining, monitoring, and securing REST and WebSocket APIs at any scale.

What is AWS Dynamodb?

• Amazon Dynamodb is a fully managed NOSQL database service that provides fast and predictable performance with seamless scalability.

Architecture:

How to run this??

    git clone git@github.com:srigumm/serverless-nodejs-aws-lambda-demo.git
    cd <<>>
    npm install

    aws config 
    **configure aws access key here

    serverless deploy

How to test this??

Curl -i -H "Content-Type: application/json" -X POST -d '{"flavour":"Strawberry","quantity":22}' https://<<your gateway url>>/dev/api/v1/ecupcakes/order

Curl -i -H "Content-Type: application/json" -X POST -d '{"flavour":"Strawberry","quantity":11}' https://<<your gateway url>>/dev/api/v1/ecupcakes/order

Curl -i -H "Content-Type: application/json" -X GET https://<<your gateway url>>/dev/api/v1/ecupcakes/order

Cleanup:

    serverless remove

2. Create a sample service (serverless framework service) project from a template

serverless create --template aws-nodejs --path <<servicename>>

This should create "serverless.yml" and "handler.js" file in your current directory

3. Deploy sample service (serverless framework service)

serverless deploy
(or)
serverless deploy function  --function <<functionamehere>>
(or)
serverless deploy --package package-path

Inspired by - https://github.com/serverless/examples/tree/master/aws-node-rest-api-with-dynamodb