Programming the Cloud with JavaScript

👍

😬

Can't see what's inside.

Can't duplicate it.

Can't scale it out easily.

Can't recover from disaster.

For one, you can't see what's inside -- you can't look at this server from the outside and see what's on it, what's installed, what version of an app we're running, and so on.
You can't duplicate it -- it's a "unique snowflake". If you had to make another one of these, you'd have to do this all this stuff all over again -- not terrible, but not a party, either.
You can't scale it out. If this app took off, and you needed like five or ten more instances of it, you've got a little work to do -- and then anything that needs doing on one of them (bumping Node, releasing an app), needs doing on all of them, and since we're human, we're likely to mess that up once in a while, too.
And you can't recover from disaster. Things go wrong. It is super simple to delete the wrong thing in a dashboard, and if those machines all disappeared and couldn't be built up from scratch easily →

⚙️ Configuration management

☁️ Provisioning

This is Chef. Chef is a configuration management tool.
This is a Chef recipe that installs the Nginx web server, sets a default document for it, and starts it.
When I run Chef with this recipe and point it at a server somewhere, Chef will "make it so" -- it will drive that server to the end state I've declared here.
If I run it again, nothing will happen, because that desired state will have been achieved.
Config management tools generally focus on taking existing infrastructure, configuring it -- installing software, creating users and files and things -- and keeping it updated over time.

Chef (Ruby)

Puppet (Puppet Language)

Terraform (HashiCorp Config Language)

They're declarative: We express the what, and the tools determine the how.

They're idempotent: Given an input, we get the same result, however many times we run it.

We built an event-driven, serverless application that blends cloud resources and app code into a single JavaScript program.

We programmed the architecture diagram.