Let’s dive into Terraform provider creation

Let’s dive into Terraform provider creation Aurélie Vache - Horacio Gonzalez 2023-02-06

Aurélie Vache @aurelievache DevRel at Conferences organizer Tech visual articles & books Sketchnoter … & ❤ Retrogaming https://www.youtube.com/c/AurelieVache https://dev.to/aurelievache/ Les Productions de MOA

Horacio Gonzalez @LostInBrittany Spaniard lost in Brittany, developer, dreamer and all-around geek

OVHcloud: A global leader Web Cloud & Telcom 30 Data Centers in 12 locations 1 Million+ Servers produced since 1999 Private Cloud 34 Points of Presence on a 20 TBPS Bandwidth Network 1.5 Million Customers across 132 countries Public Cloud 2200 Employees worldwide 3.8 Million Websites hosting Storage 115K Private Cloud VMS running 1.5 Billion Euros Invested since 2016 300K Public Cloud instances running P.U.E. 1.09 Energy efficiency indicator 380K Physical Servers running in our data centers 20+ Years in Business Disrupting since 1999 Network & Security

Warning Gophers, gophers everywhere!

Credit where it is due All the gophers you will see are drawn by Aurélie and Horacio, and are based on the Go mascot designed by Renee French which is licensed under CC BY 3.0.

Terraform De facto standard for IaC

Infrastructure as Code (IaC)

Terraform becoming the de facto standard

HashiCorp Terraform

Modular architecture: providers

Configuration packages: modules

Terraform registry

Writing Terraform providers Defining new Terraform resources

Provider SDK https://developer.hashicorp.com/terraform/plugin/sdkv2

Installing Terraform providers $ terraform init Initializing provider plugins… - Finding terraform.local/local/myprovider versions matching “0.0.1”… - Installing terraform.local/local/myprovider v0.0.1…

Installing providers from registry $ vi provider.tf terraform { required_providers { thenamespace = { source = “thenamespace/myprovider” } } } If your provider is on the official registry at https://registry.terraform.io/providers/thenamespace/myprovider

Installing providers locally $ go build -o terraform-provider-myprovider $ mkdir -p ~/.terraform.d/plugins/terraform.local/local/myprovider/0.0.1/darwin_amd64 $ mv terraform-provider-myprovider ~/.terraform.d/plugins/terraform.local/local/myprovider/0.0.1/darwin_amd64

Installing providers locally $ vi provider.tf terraform { required_providers { thenamespace = { source = “terraform.local/local/myprovider” version = “0.0.1” } } }

Do I need a Terraform provider? If you have an API, you should have a Terraform provider

Letʼs create a provider! Step by step

What do we want? ● In a simple and easy Terraform provider ● Handle cute Gophers ● In Go, because providers are made in Go 😁

Everything begins with an API https://github.com/scraly/gophers-api

For the demos we will use Gitpod Automated, ephemeral developer environments in the web

Everything begins with an API $ task swagger.serve task: [swagger.serve] swagger serve -F swagger ./pkg/swagger/swagger.yml —no-open 2022/10/31 20:16:51 serving docs at http://localhost:38457/docs

Everything begins with an API

Everything begins with an API $ task run task: [run] GOFLAGS=-mod=mod go run internal/main.go 2022/10/30 20:22:05 Serving gophers API at http://[::]:8080 $ curl localhost:8080/gophers [{“name”:”5th-element”,”displayname”:”5th Element.png”,”url”:”https://raw.githubusercontent.com/scraly/gophers/main/5th-ele ment.png”}]

Gophers deserve to be seen https://github.com/LostInBrittany/gophers-api-watcher

Everything begins with an API $ curl -X POST localhost:8080/gopher -H “Content-Type: application/json” -d \ ‘{“name”:”yoda-gopher”,”displayname”:”Yodada Gopher”,”url”:”https://raw.githubusercontent.com/scraly/gophers/main/yoda-gopher. png”}’ $ curl -X DELETE localhost:8080/gopher?name=5th-element $ curl -X PUT localhost:8080/gopher \ -H “Content-Type: application/json” -d \ ‘{“name”:”yoda-gopher”,”displayname”:”Yoda Gopher”,”url”:”https://raw.githubusercontent.com/scraly/gophers/main/yoda-gopher. png”}’

Let’s create our provider! 1. Create the skeleton of our provider thanks to scaffolding https://github.com/hashicorp/terraform-provider-scaffolding

Let’s create our provider! https://github.com/scraly/terraform-provider-gophers

Demo time!

Provider > Makefile

Demo time!

Some concepts to introduce…

Customizing provider definition

Test it! the provider $ vi provider.tf terraform { required_providers { gophers = { source = “terraform.local/local/gophers” version = “0.0.1” } } } provider “gophers” { endpoint = “http://myawesomeurl.com” }

Adding the schema “Translating” the Swagger into a Go schema

Adding datasource: gophers

Test it! $ vi gophers_data.tf # List of available gophers data “gophers” “my_gophers” { } output “return_gophers” { value = length(data.gophers.my_gophers.gophers) >= 1 }

Adding datasource: gopher

Test it! $ vi gopher_data.tf # Display information about a Gopher data “gophers_gopher” “moultipass” { name = “5th-element” }

Adding resource: gopher

Test it! $ vi gopher_resource.tf resource “gophers_gopher” “x-files” { name = “x-files” displayname = “X Files” url } = “https://raw.githubusercontent.com/scraly/gophers/main/x-files.png”

Testing the provider locally $ go build -o terraform-provider-gophers $ mkdir -p ~/.terraform.d/plugins/terraform.local/local/gophers/0.0.1/darwin_arm64 $ mv terraform-provider-gophers ~/.terraform.d/plugins/terraform.local/local/gophers/0.0.1/darwin_arm64 $ make install

Testing the provider locally $ rm .terraform.lock.hcl && terraform init $ terraform apply

Testing the provider locally $ terraform destroy

OVHcloud Terraform Provider To easily manage OVHcloud products

OVHcloud Terraform Provider https://registry.terraform.io/providers/ovh/ovh/latest/docs

OVHcloud Terraform Provider https://github.com/ovh/terraform-provider-ovh

Best practices But we have learnt with our providers

Doc is not optional $ tfplugindocs generate Generate the doc of your provider. Based on the schema the provider exposes. https://github.com/hashicorp/terraform-plugin-docs

Write useful examples in your doc Examples in your documentation should be: ● Useful ● Up-to-date ● Working Users will copy paste your examples! 😉

And… test your doc! Use the doc preview tool https://registry.terraform.io/tools/doc-preview

Acceptance tests $ make testacc $ make testacc TESTARGS=”-run TestAccDataSourceGopher”

Provider is a reflection of your API client Think about API first design

Use the logs for debugging $ TF_LOG=INFO terraform plan

Set timeouts / retry Timeouts: &schema.ResourceTimeout{ Create: schema. DefaultTimeout (20 * time.Minute), Update: schema. DefaultTimeout (20 * time.Minute), Delete: schema. DefaultTimeout (20 * time.Minute), }, Timeout/retry par resource

Read the code See how other open source providers are written

The “3 P” rule Practice, practice, practice

One more thing… Or two or three

A handy cheat sheet https://github.com/scraly/terraform-cheat-sheet/

Thank you! https://bit.ly/tf-provider-cfgmgtcamp

We ❤ feedbacks https://bit.ly/vote-tf-provider-cfgmgtcamp