Serverless

Hype or the Future?

Where is serverless in the Gartner hype cycle?

• On the Rise: 2017
• At the Peak: 2019
• Sliding Into the Trough: 2021

How much is serverless going to be adopted?

What is the future of serverless?

In the CIO’s Guide to Serverless Computing Gartner predicts that half of global enterprises will have deployed fPaaS by 2025, up from only 20% today.

Others take the opposite view that the serverless revolution has stalled

What is serverless, actually?

It’s a lambda, right?

... a cloud-native development model that allows developers to build and run applications without having to manage servers [Red Hat]

... a movement driven by developers and businesses who realize that software is eating the world [serverless.com]

... a desire to reduce the amount of Ops I have to do, reduce the configuration, improve the Time-To-Value, and focus on key features [thenewstack.io]

... a next-generation technology that enables agility, elasticity and cost-effectiveness when applied to appropriate use cases [Gartner]

Why serverless?

• No servers to provision or manage

• Scales with usage

• Availability and fault tolerance built in

• Pay for value

Sounds promising, doesn't it?

So let's build a typical web application:

... and see if the promises come true

How to build a serverless web application on  ?

 recommends the Well-Architected Framework which describes the key concepts, design principles, and architectural best practices for designing and running workloads in the cloud.

What is more, the Well-Architected Framework offers the Serverless Applications Lens which extend the Framework specifically to serverless.

Our typical web application...

...will then look like this:

How to create these services?

Nice... but how about real-life projects?

How about Infrastructure as Code?

Are there any alternatives?

offers great support:

• Command Line Interface (CLI)
• Software Development Kits (SDKs)
• CloudFormation
• Serverless Application Model (SAM)

So do open source frameworks:

• 
• Zappa

Let's give a try as it...

• supports all languages
• offers options for offline development
• is provider-agnostic (AWS, Microsoft Azure, Google Cloud Platform, etc.)
• uses CloudFormation under the hood (when deploying on AWS)
• has great community
• is well documented
• offers many plugins
• Mentioned among developer tools in AWS docs

Let's set up our environment:

1. Create an IAM user with programmatic access to your account:
2. Install the CLI
3. Set up a named profile for your account using the credentials of the IAM user created in step .1:

   aws configure --profile=tech_talk

   export AWS_PROFILE=tech_talk

4. Install the Serverless Framework:

   npm install -g serverless

How much work does serverless take off our hands?

• Logging / tracing
• API Gateway (exposing to public)
• Amplify lib simplifies client development
• API Gateway integrates seamlesly with Amazon Cognito

• Creates CloudFormation stacks behind the scenes
• library to put an express app into a lambda function
• Excluding dev dependencies when deploying
• Website component cares about History API fallback and caching invalidation
• Serverless Plugin to enable DynamoDB local
• New environment -> define new stage

What is (were) serverless not so good for?

• exceeds Lambda's quotas, e.g.: timeout: 15 minutes, memory: 10 GB, payloads: 6 MB
• has high, predictable and stable loads -> cost can be much more expensive than traditional VMs (e.g. EC2)
• needs to keep state, e.g.: JDBC connections to SQL databases; can be fixed by Data API or RDS Proxy
• cold start is an issue; can be fixed by provisioned concurrency

Cost estimation

• is becoming a science in itself 
• Serverless Functions can save big money, but they can also cost big money
• should take the Total Cost of Ownership (TCO) into account: development + infrastructure + maintenance
• Serverless Survey: +77% Delivery Speed, 4 Dev Workdays/Mo Saved & -26% AWS Monthly Bill

What will serverless change?

• Flexible software architectures allowing switching between different deployment models (VMs, containers, functions) -> hexagonal, DDD
• Event driven architecture -> asynchronous, functional and reactive programming paradigms
• More lightweight frameworks needed, e.g.: Middy instead of Express

Serverless enables green computing

• The carbon footprint from the Information and Communication sector is about 1.4% of overall global emissions; air transport 1.9%...
• 30% of the world’s servers are unused at any point in time and most servers only utilize 5%-15% of their total capacity
• Serverless computing ensures organizations don’t over-utilize electricity

Questions?

Slides available at: https://serverless-intro.github.io/