1. What is this “FaaS”?
This tutorial uses [Minikube](https://github.com/kubernetes/minikube) to createa local kubernetes cluster. This tutorial uses [Docker for Mac](https://docs.docker.com/engine/installation/mac/) as the host of Minikube.
What is this “FaaS”?
What is this “FaaS” thing everyone talking about? I don’t want a “microservice”, I want a big service that makes me lots of money!
What is Function-as-a-Service (FaaS)?
FaaS is the concept of serverless computing with serverless architectures. Software developers can use this to deploy an individual function (Piece of code), that performs an action, or piece of business logic, without worrying about where they are running it (eg. serverless). They are expected to start within milliseconds and process individual requests and then the process ends. Sounds simple right?
Principles of FaaS:
- Completely takes the pain of servers and environment constraints away from the developer
- Billing based on consumption and executions, not server instance sizes
- Services that are event-driven and instantaneously scalable
At the basic level, you could describe them as a way to run some code when a “thing” happens. Shows how easy it is to process an HTTP request as a “Function”.
Benefits & Use Cases
Like most things, FaaS is not going to be perfect for every app.
In general, we see companies and developers using them mostly for our very high volume transactions so that they can scale when needed and don’t have to have redundant servers the rest of the time.
- High volume transactions — Isolate them and scale them
- Dynamic or burstable workloads — If you only run something once a day or month, no need to pay for a server 24/7/365
- Scheduled tasks — They are a perfect way to run a certain piece of code on a schedule, think cron jobs.
Types of Functions
There are a lot of potential uses for functions. Below is a simple list of some common scenarios. Support and implementation for them vary by the provider or service your using.
- Scheduled tasks or jobs.
- Process a web request.
- Process queue messages.
- Run manually.
Summary
Developers hate servers and server management. The idea of serverless architectures is a dream came true for most developers. That said, I can’t see FaaS as being a complete replacement for normal application architectures. For example a basic web application, it would take a lot of functions.
In my humble opinion, function-based apps are a perfect fit for replacing microservice style architectures and smaller high volume back-end services.
Brian Mathews @DevOps4Days