Basic Terraform Commands

# Lab 1 - HCL Basics
resource "local_file" "pets" {
    filename = "pets.txt"
    content = "I love Pets!"
}


# Lab 2 - Update and Destroy Infrastructure in Terraform
resource "local_file" "pets" {
    filename = "pets.txt"
    content = "we love!TF"
    file_permission = "0700"
}
terraform destroy

# Lab 3 - Terraform Providers in Terraform

terraform init 

# Lab 4 - Multiple Providers in Terraform
terraform init 
resource "local_file" "pet" {
    filename = "pets.text"
    content = "we love pets!!!!"
}

resource "random_pet" "my-pet" {
    prefix = "mrs"
    separator =  "."
    length = "13"  
  
}

# Lab 5 - Input Variables in Terraform +
# Lab 6 - Using Variables in Terraform
resource "local_file" "pet" {
    filename = var.filename
    content = var.content
}

resource "random_pet" "my-pet" {
    prefix = var.prefix
    separator =  var.separator
    length = var.length  
  
}
####== variable.tf ==##############

variable "filename" {
  default = "pets.text"
}
variable "content" {
  default =  "we love Bangladesh!"
  
}
variable "prefix" {
  default = "Mr"

}
variable "separator" {
  default = "."
}
variable "length" {
  default = "1"
}
#################################


resource "local_file" "pets" {
    filename = var.filename
    content = var.content["statement2"]
}

# Lab 7 - Resource Attribute Reference in Terraform
resource "local_file" "pet" {
    filename = var.filename
    content = "My favorite pet is ${random_pet.my-pet.id}"
}

resource "random_pet" "my-pet" {
    prefix = var.prefix
    separator =  var.separator
    length = var.length  
  
}

# Lab 8 - Resource Dependencies in Terraform
resource "local_file" "pet" {
    filename = var.filename
    content = "My favorite pet is ${random_pet.my-pet.id}"

    depends_on = [
      random_pet.my-pet
    ]
}

resource "random_pet" "my-pet" {
    prefix = var.prefix
    separator =  var.separator
    length = var.length  
  
}

# Lab 9 - Output Variables in Terraform
output pet-name {
  value = random_pet.my-pet.id
  description = "Output the value"
}

# Lab 10 - Purpose of State in Terraform
resource "local_file" "pet" {
    filename = "pets.txt"
    content = "My favorite pet is ${random_pet.my-pet.id}"

}

resource "random_pet" "my-pet" {
    length = 1 
}

resource "random_pet" "cat" {
    filename = "cat.txt"
    content = "I like cats too!" 
}

# Lab 11 - Terraform Commands
# terraform init 
# terraform plan
# terraform apply  
# terraform destroy
# terraform apply -var "filename=pets2.text"
# terraform validate 
# terraform show
# terraform show -json
# terraform fmt
# terraform providers
# terraform output
# terraform refresh
# terraform graph

# Mutable vs Immutable Infrastructure
Mutable = Created a web server and deployed it on existing mutable infrastructure
Immutable = “Immutable” is the state of being unchangeable. It’s an antonym to mutable, which means that on this end, the infrastructure cannot be modified
 once deployed. When changes are necessary, you need to deploy afresh, add infrastructure, and decommission old infrastructure.

# Lab 12 - Lifecycle Rules in Terraform

resource "local_file" "pets" {
    filename = "pets.txt"
    content = "we love!TF"
    file_permission = "0700"

    lifecycle {
      create_before_destroy = true
    }
}
------------------------------------------

resource "local_file" "pets" {
    filename = "pets.txt"
    content = "we love!TF"
    file_permission = "0700"

    lifecycle {
      prevent_destroy = true
    }
}

------------------------------------------

resource "aws_instance" "test" {
  ami   = "ami-062df10d14676e201"
  instance_type =  "t2.micro"
  subnet_id = "subnet-016875cc812b02b0b"
  tags = {
    Name = "ProjectA-Webserver"
  }
  lifecycle{
    ignore_changes = [
      tags
    ]
  }
}

# Lab 13 - Data Sources in Terraform
resource "local_file" "pets" {
    filename = "pets.txt"
    content = data.local_file.dog.content
}
data "local_file" "dog"{
  filename = "dog.txt"
}


# Lab 14 - Use of for_each meta arguments in Terraform
resource "local_file" "pet" {
    #filename = var.filename[count.index]
    #count = length(var.filename)
    filename = each.value
    #for_each = toset(var.filename)
    for_each = var.filename
}
##############= variables.tf =###############
variable "filename" {
 # type=list(string)
 type=set(string)
  default = [
    "pets.txt",
    "dogs.txt",
    "cats.txt"
  ]
}

-------------------------------------------------------

terraform {
  required_providers {
    local = {
      source  = "hashicorp/local"
      version = "~> 1.4.0"
    }
  }
}


# https://www.youtube.com/watch?v=YcJ9IeukJL8