JAX-2022: YATT: Yet another Terraform talk - Grundlagen und ein bisschen mehr

"Infrastructure as Code" ist heutzutage eine wichtige Komponente, um die Erstellung von Cloud-Umgebungen gut strukturieren, versionieren und verwalten zu können. Als eines der führenden Tools für diesen Zweck gilt HashiCorp Terraform. Ich möchte in meinem Vortrag Grundlagen und Konzepte erklären und einen kleinen Einblick geben, was noch alles machbar ist. Seid gespannt auf die tollen Features, die Terraform außer dem stumpfen Auflisten von Ressourcen noch zu bieten hat.

Transcript

1. @stgerberding YATT: Yet another T erraform talk - Grundlagen und ein bisschen mehr ... Sandra Gerberding - smartsteuer GmbH
2. @stgerberding Software-Entwicklerin: Java Web Anwendungen Continuous Integration Software-Architektur T witter: 
 @stgerberding Blog: 
 http://sandra.gerberding.blog E-Mail: 
 sandra.gerberding@smartsteuer.de Speaker Deck: 
 https://speakerdeck.com/sandrag Sandra Gerberding 2
3. @stgerberding Was ist Infrastructure as Code (IaC)? Network Security Server Storage Repository
4. @stgerberding Con fi guration Management Provisioning T ool
5. @stgerberding Mutable Approach Immutable Approach
6. @stgerberding Declarative Approach Procedural Approach
7. @stgerberding Was ist T erraform? … Apply Plan
8. @stgerberding T erraform Core /CLI Provider-Plugins Provisioner-Plugins Cloud API Client Library RPC Golang HTTPS https://registry.terraform.io/providers/hashicorp/aws/latest/docs Aufbau T erraform
9. @stgerberding Syntax T erraform Argumente HCL Syntax .tf Blöcke identifier = expression type [label] { Block body [arguments/blocks ] } UTF-8 Kommentare # einzeili g // einzeili g /*…*/ mehrzeilig JSON Syntax .tf.json UTF-8 JSON Property JSON Object "identifier": "expression" "identifier": { Object body [properties/objects/arrays ] } Kommentare "//": "This …" JSON Array "identifier": [ Object body [properties/objects/arrays ] ]
10. @stgerberding terraform { required_version = ">= 1.0 “ required_providers { aws = { source = "hashicorp/aws " version = "~> 3.56.0 " } } } provider "aws" { region = "eu-central-1" profile = "profile-name " } resource "aws_instance" "project-server" { ami = "ami-029c64b3c205e6cce " instance_type = "t4g.micro " tags = { Name = "Default Instance" } } HCL T erraform Beispiel { "terraform": { "required_version": ">= 1.0" , "required_providers": { "aws": { "source": "hashicorp/aws" , "version": "~> 3.56.0 " } } } , "provider": { "aws": { "region": "eu-central-1" , "profile": "profile-name " }} , "resource": { "aws_instance": { "project-server": { "ami": "ami-029c64b3c205e6cce" , "instance_type": "t4g.micro" , "tags": { "Name": "Default Instance " } } } } } JSON T erraform Beispiel
11. @stgerberding Resources Input Variables Output Values Local Values Modules
12. @stgerberding Resources resource "aws_instance" "project-server" { ami = "ami-029c64b3c205e6cce " instance_type = "t4g.micro " } <Resource_type>.<Name>.<Attribute> foobar = aws_instance.project-server.i d De fi nition Benutzung
13. @stgerberding Input Variables variable "image_id" { type = strin g description = "The id of the machine image (AMI) to use for the server. " default = "ami-029c64b3c205e6cce " validation { condition = length(var.image_id) > 4 && substr(var.image_id, 0, 4) == "ami- " error_message = "The image_id value must be a valid AMI id, starting with \"ami-\". " } } De fi nition Benutzung foobar = var.image_i d var.<Name>
14. @stgerberding Auswertung-Hierarchie Überschreibt • Environment Variablen • terraform.tfvars Datei • terraform.tfvars.json • *.auto.tfvars / *.auto.tfvars.json • -var / -var- fi le >export TF_VAR_image_id=ami-abc12 3 region = "us-east-2 " project = "workshop " stage = "testing " image_id = "ami-029c64b3c205e6cce" >terraform apply -var-file="testing.tfvars " >terraform apply -var="image_id=ami-abc123 "
15. @stgerberding Output Values output "ec2_instance_public_ip" { value = aws_instance.project-server.public_i p } De fi nition module.<MODULE NAME>.<OUTPUT NAME> Benutzung Apply complete! Resources: 1 added, 0 changed, 0 destroyed . Outputs : hostname = terraform.example.co m private_ip = 10.5.4.8 2 public_ip = 94.237.45.22 1 foobar = module.my-module.ec2_instance_public_i p
16. @stgerberding Local Values locals { /*------------------------------------------------------------- - RDS (database ) --------------------------------------------------------------* / rds_instance_allocated_storage = var.stage == "dev" ? 5 : 1 0 rds_instance_class = var.stage == "dev" ? "db.t3.micro" : "db.t2.large " rds_database_name = var.stage == "dev" ? "projectdevdb" : "projectproddb " rds_database_user_name = "dbuser " rds_database_backup_retention_period = 1 4 rds_database_deletion_protection = var.stage == "dev" ? false : tru e } De fi nition name = local.rds_database_nam e Benutzung local.<Name>
17. @stgerberding Modules Root Module Database Module Server Module Network Module etc. Module Output Value Input Variables Input Variables Input Variables Input Variables
18. @stgerberding Verzeichnisse und Dateien
19. @stgerberding Modules module "network" { source = "./modules/network" base_cidr_block = "10.0.0.0/8 " } module "database" { source = "./modules/database " database_name = "myDatabase " vpc_id = module.network.vpc_i d subnet_ids = module.network.subnet_ids } module "consul" { source = "hashicorp/consul/aws " version = "0.0.5" servers = 3 } T erraform Registry main.tf aus dem Root Verzeichnis main.tf aus dem Root Verzeichnis
20. @stgerberding Expressions "true" converts to true / "5" converts to 5 // Type conversio n "Hello, ${var.name}!" // String interpolatio n [for o in var.list : o.id] // for expressio n var.list[*].id // splat expressio n var.dbname != "" ? var.dbname : "default-dbname" // conditional expressio n
21. @stgerberding resource_prefix = join("-", [var.project, var.stage]) // project-tes t substr("hello world", 1, 4) // ell o concat(["a", ""], ["b", "c"]) // ["a", "", "b", "c" ] contains(["a", "b", "c"], "a") // tru e base64decode("SGVsbG8gV29ybGQ=") // Hello Worl d fileexists("${path.module}/hello.txt") Functions
22. @stgerberding Loops count -> loop über resources resource "aws_instance" "server" { ami = data.aws_ami.amazon_linux_2_arm64.image_i d instance_type = "t2.micro " count = length (var.server_names ) tags = { name = var.server_names[count.index ] } } resource "aws_instance" "server" { ami = data.aws_ami.amazon_linux_2_arm64.image_i d instance_type = "t2.micro " for_each = toset(var.server_names ) tags = { name = each.valu e } } variable "server_names" { description = "Create server with these names " type = list(string ) default = ["neo", "trinity", "morpheus" ] } output "upper_server_names" { value = [for name in var.server_names : upper(name) ] } for_each -> loop über resources und inline Blöcke for -> loop über lists und maps
23. @stgerberding > terraform init > terraform plan > terraform apply > terraform destroy T erraform CLI https://www.terraform.io/docs/cli/commands/index.html > terraform > terraform init -help T erraform CLI > terraform output > terraform import > terraform console > terraform validate > terraform fmt …
24. @stgerberding DEMO
25. @stgerberding T erraT est https://terratest.gruntwork.io/
26. @stgerberding Ausblick T erraform CDK (beta)
27. @stgerberding Zusammenfassung
28. @stgerberding Vielen Dank für Eure Aufmerksamkeit! @stgerberding 
 http://sandra.gerberding.blog 
 sandra.gerberding@smartsteuer.de 
 https://speakerdeck.com/sandrag