less

Simple Go serverless website on Amazon Web Services (AWS).
Demo: https://6epko5iya8.execute-api.ap-southeast-1.amazonaws.com/dev.

Website's frontend is written in VueJS, which stored on a public AWS S3 bucket.
There're two simple AWS Lambdas written in Go (deployed via apex with NodeJS shim runtime):

• less_crawler: Crawls Github trending repositories, parses and persists data to DynamoDB. This function is triggered by a CloudWatch cron job.
• less_caterer: Receives HTTP request from client and lookup on DynamoDB for trending repositories by day.

API Gateway serves two APIs, one to GET the index.html page on S3 bucket (forward/proxy request to the URL of index.html file on S3). The other allows client to lookup Gihub trending repositories by day (which calling the less_caterer lambda).

Architecture

This repo contains the code for Lambda and S3 parts in the image below.

Deploy on AWS

Local development

You have to install Go SDK, glide, AWS CLI, apex and configure the AWS credential to deploy your functions on AWS Lambda.

• Clone the repository to your local $GOPATH and install Go dependencies:

  $ go get github.com/lnquy/less
  $ cd $GOPATH/src/github.com/lnquy/less
  $ glide install

• The AWS region is ap-southeast-1, you have to take a look on the functions code and change the awsRegion value to deploy on another region.

Lambdas

• Create a role for the Lambdas on AWS IAM which have access to DynamoDB service.

• Change the role to match your IAM Lambda role: project.json#L4.

• Deploy to AWS:

  $ apex deploy  

Frontend and S3

• Create a public S3 bucket for static web hosting, get the URL of the bucket.

• Change the publicPath to your S3 bucket URL: webpack.config.js#L6

• Change the GetCaterer to your POST /api/v1/trending/ API URL: main.js#L22

• Build frontend:

  $ cd frontend
  $ npm install   // or yarn
  $ npm run build
  

• Upload all frontend/dist files to the root of S3 bucket, make sure all files has public read permission.

• Note the HTTP URL to the index.html file.

CloudWatch

• Create a 24_hours interval scheduled job.
• Apply that job as the trigger of the less_crawler lambda.

DynamoDB

• Create a table with name of less-crawler-dev or anything you want, just make sure to change the dynamoTable value in Go code, too.

• Primary partition key: date (String).

• Primary sort key: sort (Number).

API Gateway

• Create a root / GET API to forward/proxy the HTTP request to the URL of index.html file on S3 bucket.
• Create a /api/v1/trending POST API which called the less_caterer lambda.
• You may have to allow the CORS permission on APIs, too.
• Deploy the APIs to a stage (E.g: dev).

Open browser and follow the link to the GET / API, you now have a simple serverless website up and running on AWS. Congrats :)

License

This project is under the MIT License. See the LICENSE file for the full license text.