# GCP Terraform

## Install in Ubuntu

$ wget -O- https://apt.releases.hashicorp.com/gpg | sudo gpg --dearmor -o /usr/share/keyrings/hashicorp-archive-keyring.gpg
echo "deb [signed-by=/usr/share/keyrings/hashicorp-archive-keyring.gpg] https://apt.releases.hashicorp.com $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/hashicorp.list
sudo apt update && sudo apt install terraform

$ terraform -help

## 需要一個IAM才可以使用terraform
+ step1. 創建user

+ step2. 創建Key

+ step3. 上傳key

## Project1.

+ 目的
創建bucket

+ folder structure

$ ls
key.json  main.tf

+ main.tf

provider "google" {
  credentials = "${file("key.json")}"
  project = "[your project id]"
  region  = "asia-east1"
}

resource "google_storage_bucket" "quick-start-gcs" {
  name          = "[your bucket name]"
  location      = "asia-east1"
  force_destroy = true
}

+ 執行指令

$ terraform init (初始化)
$ terraform fmt  (程式碼優化排版)
$ terraform plan (測試程式碼是否可以佈署)
$ terraform apply --auto-approve (真正開始佈署)
$ terraform destroy --auto-approve (刪除程式碼佈署的所有東西)

+ 結果

## Project2.

+ 目的
創建instance

+ folder structure

$ ls
key.json  main.tf  provider.tf

+ 程式碼

- main.tf

    resource "google_compute_instance" "example" {
      name         = "example-instance"
      machine_type = "e2-micro"
      zone         = "asia-east1-b"

      boot_disk {
        initialize_params {
          image = "projects/ubuntu-os-cloud/global/images/ubuntu-2204-jammy-v20240726"
        }
      }

      network_interface {
        network = "default"

        access_config {
          // Ephemeral IP
        }
      }
    }

- provider.tf

    ##################################################################################
    # CONFIGURATION
    ##################################################################################
    terraform {
      # 指定 terraform 的最小版本
      required_version = ">=1.0"

      required_providers {
        # provider 中的最小版本
        google = {
          source  = "hashicorp/google"
          version = ">= 4.40.0"
        }
      }
    }
    ##################################################################################
    # PROVIDERS
    ##################################################################################
    provider "google" {
      # your project name
      credentials = file("key.json")
      project     = "avian-casing-435202-m5"
    }

+ 執行指令

$ terraform init (初始化)
$ terraform fmt  (程式碼優化排版)
$ terraform plan (測試程式碼是否可以佈署)
$ terraform apply --auto-approve (真正開始佈署)
$ terraform destroy --auto-approve (刪除程式碼佈署的所有東西)

+ 結果

## Project3.

+ 目的
檢查虛擬機是否存在，並獲取虛擬機的各種資訊

+ folder structure

$ ls
key.json  main.tf

+ main.tf

resource "google_compute_instance" "example" {
  name         = "example-instance"
  machine_type = "e2-micro"
  zone         = "asia-east1-b"

  boot_disk {
    initialize_params {
      image = "projects/ubuntu-os-cloud/global/images/ubuntu-2204-jammy-v20240726"
    }
  }

  network_interface {
    network = "default"

    access_config {
      // Ephemeral IP
    }
  }

  # 成功案例，執行電腦本機路徑
  provisioner "local-exec" {
    command = "echo ${google_compute_instance.example.network_interface[0].network_ip} > ./ip_address_local_exec.txt"
  }

  # # 失敗案例，傳送到虛擬電腦本機
  # provisioner "file" {
  #   content     = google_compute_instance.example.network_interface[0].network_ip
  #   destination = "/tmp/ip_address_file.txt"
  # }

  # # 失敗案例，無法連線到遠端
  # provisioner "remote-exec" {
  #   inline = [
  #     "echo ${google_compute_instance.example.network_interface[0].network_ip} > /tmp/ip_address_remote_exec.txt"
  #   ]
  # }
}

+ 執行指令

$ terraform init (初始化)
$ terraform fmt  (程式碼優化排版)
$ terraform plan (測試程式碼是否可以佈署)
$ terraform apply --auto-approve (真正開始佈署)
$ terraform destroy --auto-approve (刪除程式碼佈署的所有東西)

+ 結果

$ ls
ip_address_local_exec.txt  key.json  main.tf  terraform.tfstate
$ cat ip_address_local_exec.txt 
10.140.0.3