Open Source For Geeks: 10/05/18

Friday, 5 October 2018

Building a web application using AWS serverless architecture

Background

The last couple of weeks I have tried to record Youtube videos to demonstrate how to build a web application using AWS serverless architecture.

Serverless essentially means you do not have to worry about the physical hardware or the operating system or the runtimes. It's all taken care by the service offered under the serverless architecture. This has essentially given way to "Function as a service".

In this post, I will try to summarize what I have covered in those videos over the last 2 week so that anyone looking to put it all together can refer.

If you do not wish to proceed and are just interested in the video links here's a list of them -

AWS Serverless 101(Building a web application): https://youtu.be/I5bW0Oi0tY4
AWS Serverless 102(Understanding the UI code): https://youtu.be/dQJCr0r_RuM
AWS Serverless 103(AWS Lambda): https://youtu.be/Kn86Lq29IMA
AWS Serverless 104(API Gateway): https://youtu.be/yKI_UCYblio
AWS Serverless 105(CI/CD with code pipeline): https://youtu.be/GEWrpZuBEkQ
AWS Serverless 106(Cloudwatch Events): https://youtu.be/9gUB2n0hV7Q
AWS Serverless 107(Step functions): https://youtu.be/rL6EqaMbC5U

Github repo: https://github.com/aniket91/AWS_Serverless

I will go over each of the topics and explain what has been covered in each of the videos. If you think a specific topic interests you, you can pick that up. However, note that some videos might have references to setup done in previous videos. So it is recommended to go through them in the order provided.

AWS Serverless 101(Building a web application)

Video: https://youtu.be/I5bW0Oi0tY4

This video is primarily to introduce you to the world of serverless. It covers a bit of cloud deployment history, information about serverless architecture - What and Why?. It also covers what are the prerequisites for this series and what exactly are we trying to build here. If you are completely new to AWS or AWS serverless concept this is a good place to start.

This web application has a UI with a button on click on which an API call is made to get all the image files from an S3 bucket and are rendered on the UI. API call goes to API Gateway which forwards the request to Lambda. Lambda executes to get all the image files from S3 and returns it to API gateway which in turn returns the response to the UI code(javascript). Response is then parsed as json array and images are rendered on UI.

AWS Serverless 102(Understanding the UI code)

Video: https://youtu.be/dQJCr0r_RuM

This video covers the UI component of the web application. This is in plain HTML and javascript. UI code is hosted on a static website in an S3 bucket.

AWS Serverless 103(AWS Lambda)

Video: https://youtu.be/Kn86Lq29IMA

AWS Lambda forms the basic unit of AWS serverless architecture. This video talks about AWS Lambda - what is Lambda, How to configure it, How to use it and finally code to get the list of files from an S3 bucket.

AWS Serverless 104(API Gateway)

Video: https://youtu.be/yKI_UCYblio

API Gateway is an AWS service to create and expose APIs. This video talks about API Gateway service - how you can create APIs, resources, and methods, How we can integrate API gateway with Lambda. How to create stages and see corresponding endpoints. It also talks about CORS and logging in the API gateway service.

AWS Serverless 105(CI/CD with code pipeline)

Video: https://youtu.be/GEWrpZuBEkQ

This video shows how we can automate backend code deployment using code pipeline AWS service. This includes using Code pipeline, Code build, and Cloud formation services.

AWS Serverless 106(Cloudwatch Events)

Video: https://youtu.be/9gUB2n0hV7Q

This video shows how you can use Cloud watch events to trigger or schedule periodic jobs just like cron jobs in a Linux based system. We are using this service to do a periodic cleanup for non-image files in the S3 bucket.

AWS Serverless 107(Step functions)

Video: https://youtu.be/rL6EqaMbC5U

This video covers how to use state machines of AWS step functions service to build distributed applications using visual workflows. We are using this service to do a asynchronous processing of various image files like jpg, png etc.