Terraform 扩展

`Terraform` `Meta-Arguments` 元参数

count 创建相似的资源
for_each 创建相似的资源
depends_on 定义资源或者模块的依赖
provider 定义provider选项
lifecycle 资源的生命周期行为

参数	使用范围	备注
count	resource module	适用于创建多个相似的资源，使用索引count.index作为参数引用。如果资源存在区别，建议使用 for_each
for_each	resource module	for_each 它只能用于set(string) 或者map(string)
depends_on	resource module	处理 Terraform 无法自动推断的资源或模块之间的依赖关系
provider	resource module	在资源中定义供应商，通常是 . ，模块中，如果子模块未定义providers则继承父模块
lifecycle	resource module	生命周期行为定义

`Count` 创建资源副本

count = num数值类型，可以通过 length() 计算数量；
count.index 索引来遍历列表

示例：创建三条 DNS 记录

`Terraform` 配置

## count.tf

locals {
    zone = "evescn.com"
    records = ["devops1","devops2","devops3"]
}

resource "alicloud_dns_record" "record" {
  count = length(local.records)
  name        = local.zone
  host_record = local.records[count.index]
  type        = "A"
  value       = "192.168.1.1"
}

## count.tf

locals {
    zone = "evescn.com"
    records = ["devops1","devops2","devops3"]
}

resource "alicloud_dns_record" "record" {
  count = length(local.records)
  name        = local.zone
  host_record = local.records[count.index]
  type        = "A"
  value       = "192.168.1.1"
}

创建 DNS 解析

evescn@evescndeMacBook-Pro count % terraform init

Initializing the backend...

Initializing provider plugins...
- Finding hashicorp/alicloud versions matching "1.164.0"...
- Installing hashicorp/alicloud v1.164.0...
- Installed hashicorp/alicloud v1.164.0 (signed by HashiCorp)

Terraform has been successfully initialized!

evescn@evescndeMacBook-Pro count % terraform fmt 
count.tf

evescn@evescndeMacBook-Pro count % terraform validate
Success! The configuration is valid.

evescn@evescndeMacBook-Pro count % terraform plan    

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # alicloud_dns_record.record[0] will be created
  + resource "alicloud_dns_record" "record" {
      + host_record = "devops1"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

  # alicloud_dns_record.record[1] will be created
  + resource "alicloud_dns_record" "record" {
      + host_record = "devops2"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

  # alicloud_dns_record.record[2] will be created
  + resource "alicloud_dns_record" "record" {
      + host_record = "devops3"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

Plan: 3 to add, 0 to change, 0 to destroy.


evescn@evescndeMacBook-Pro count % terraform apply --auto-approve

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # alicloud_dns_record.record[0] will be created
  + resource "alicloud_dns_record" "record" {
      + host_record = "devops1"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

  # alicloud_dns_record.record[1] will be created
  + resource "alicloud_dns_record" "record" {
      + host_record = "devops2"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

  # alicloud_dns_record.record[2] will be created
  + resource "alicloud_dns_record" "record" {
      + host_record = "devops3"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

Plan: 3 to add, 0 to change, 0 to destroy.
alicloud_dns_record.record[1]: Creating...
alicloud_dns_record.record[0]: Creating...
alicloud_dns_record.record[2]: Creating...
alicloud_dns_record.record[0]: Creation complete after 1s [id=843289465596745728]
alicloud_dns_record.record[1]: Creation complete after 1s [id=843289465605112832]
alicloud_dns_record.record[2]: Creation complete after 1s [id=843289465619789824]

Apply complete! Resources: 3 added, 0 changed, 0 destroyed.

删除 devops2 记录，会成功运行？

locals {
  zone    = "evescn.com"
  # records = ["devops1", "devops2", "devops3"]
  records = ["devops1", "devops3"]
}

resource "alicloud_dns_record" "record" {
  count       = length(local.records)
  name        = local.zone
  host_record = local.records[count.index]
  type        = "A"
  value       = "192.168.1.1"
}

执行部署

evescn@evescndeMacBook-Pro count % terraform plan                
alicloud_dns_record.record[0]: Refreshing state... [id=843289465596745728]
alicloud_dns_record.record[2]: Refreshing state... [id=843289465619789824]
alicloud_dns_record.record[1]: Refreshing state... [id=843289465605112832]

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  ~ update in-place
  - destroy

Terraform will perform the following actions:

  # alicloud_dns_record.record[1] will be updated in-place
  ~ resource "alicloud_dns_record" "record" {
      ~ host_record = "devops2" -> "devops3"
        id          = "843289465605112832"
        name        = "evescn.com"
        # (7 unchanged attributes hidden)
    }

  # alicloud_dns_record.record[2] will be destroyed
  # (because index [2] is out of range for count)
  - resource "alicloud_dns_record" "record" {
      - host_record = "devops3" -> null
      - id          = "843289465619789824" -> null
      - locked      = false -> null
      - name        = "evescn.com" -> null
      - priority    = 0 -> null
      - routing     = "default" -> null
      - status      = "ENABLE" -> null
      - ttl         = 600 -> null
      - type        = "A" -> null
      - value       = "192.168.1.1" -> null
    }

Plan: 0 to add, 1 to change, 1 to destroy.

evescn@evescndeMacBook-Pro count % terraform apply --auto-approve
alicloud_dns_record.record[1]: Refreshing state... [id=843289465605112832]
alicloud_dns_record.record[0]: Refreshing state... [id=843289465596745728]
alicloud_dns_record.record[2]: Refreshing state... [id=843289465619789824]

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  ~ update in-place
  - destroy

Terraform will perform the following actions:

  # alicloud_dns_record.record[1] will be updated in-place
  ~ resource "alicloud_dns_record" "record" {
      ~ host_record = "devops2" -> "devops3"
        id          = "843289465605112832"
        name        = "evescn.com"
        # (7 unchanged attributes hidden)
    }

  # alicloud_dns_record.record[2] will be destroyed
  # (because index [2] is out of range for count)
  - resource "alicloud_dns_record" "record" {
      - host_record = "devops3" -> null
      - id          = "843289465619789824" -> null
      - locked      = false -> null
      - name        = "evescn.com" -> null
      - priority    = 0 -> null
      - routing     = "default" -> null
      - status      = "ENABLE" -> null
      - ttl         = 600 -> null
      - type        = "A" -> null
      - value       = "192.168.1.1" -> null
    }

Plan: 0 to add, 1 to change, 1 to destroy.
alicloud_dns_record.record[2]: Destroying... [id=843289465619789824]
alicloud_dns_record.record[1]: Modifying... [id=843289465605112832]
alicloud_dns_record.record[2]: Destruction complete after 1s
╷
│ Error: [ERROR] terraform-provider-alicloud/alicloud/resource_alicloud_dns_record.go:138: Resource 843289465605112832 UpdateDomainRecord Failed!!! [SDK alibaba-cloud-sdk-go ERROR]:
│ SDK.ServerError
│ ErrorCode: DomainRecordDuplicate
│ Recommend: https://api.aliyun.com/troubleshoot?q=DomainRecordDuplicate&product=Alidns
│ RequestId: 17F3D4A1-6E02-5F4E-AEA0-C04C583B9A9E
│ Message: The DNS record already exists.
│ RespHeaders: map[Access-Control-Allow-Origin:[*] Access-Control-Expose-Headers:[*] Connection:[keep-alive] Content-Length:[246] Content-Type:[application/json;charset=utf-8] Date:[Wed, 02 Aug 2023 03:39:11 GMT] Keep-Alive:[timeout=25] X-Acs-Request-Id:[17F3D4A1-6E02-5F4E-AEA0-C04C583B9A9E] X-Acs-Trace-Id:[df248ca1dac580f3e90c12bf599c4e1a]]
│ 
│   with alicloud_dns_record.record[1],
│   on count.tf line 7, in resource "alicloud_dns_record" "record":
│    7: resource "alicloud_dns_record" "record" {
│

从 terraform 看，程序执行的操作步骤如下：

update： server2 > server3
destroy： server3

但是在执行过程中 count = length(local.records) 命令获取不了 [2] 这个下标程序出错，看看 DNS 解析记录

`for_each` 创建资源副本

for_each = set(string) map(string)
for_each 只能用于 set(string) 或者 map(string)，可以使用 toset 转换 list 为 set 数据
for_each = set(string)
- each.key = each.value
for_each = map(string)
- each.key = key
- each.value = value

示例：创建三条 DNS 记录

`Terraform` 配置

## version.tf

terraform {
  required_version = ">=1.1.9"
  required_providers {
    alicloud = {
      source  = "hashicorp/alicloud"
      version = "1.164.0"
    }
  }
}

# Configure the Alicloud Provider
provider "alicloud" {
  access_key = "xxxxxxxx"
  secret_key = "xxxxxxxx"
}

## for_each.tf

locals {
  zone = "evescn.com"
  # records = ["devops1", "devops2", "devops3"]
  records = ["devops1", "devops3"]
}

resource "alicloud_dns_record" "eachrecord" {
  for_each    = toset(local.records)
  name        = local.zone
  host_record = each.value
  type        = "A"
  value       = "192.168.1.1"
}

创建 DNS 解析

evescn@evescndeMacBook-Pro for_each % terraform init

Initializing the backend...

Initializing provider plugins...
- Finding hashicorp/alicloud versions matching "1.164.0"...
- Installing hashicorp/alicloud v1.164.0...
- Installed hashicorp/alicloud v1.164.0 (signed by HashiCorp)

Terraform has been successfully initialized!

evescn@evescndeMacBook-Pro for_each % terraform fmt 
for_each.tf

evescn@evescndeMacBook-Pro for_each % terraform validate
Success! The configuration is valid.

evescn@evescndeMacBook-Pro for_each % terraform apply   

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # alicloud_dns_record.eachrecord["devops1"] will be created
  + resource "alicloud_dns_record" "eachrecord" {
      + host_record = "devops1"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

  # alicloud_dns_record.eachrecord["devops2"] will be created
  + resource "alicloud_dns_record" "eachrecord" {
      + host_record = "devops2"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

  # alicloud_dns_record.eachrecord["devops3"] will be created
  + resource "alicloud_dns_record" "eachrecord" {
      + host_record = "devops3"
      + id          = (known after apply)
      + locked      = (known after apply)
      + name        = "evescn.com"
      + routing     = "default"
      + status      = (known after apply)
      + ttl         = 600
      + type        = "A"
      + value       = "192.168.1.1"
    }

Plan: 3 to add, 0 to change, 0 to destroy.

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

alicloud_dns_record.eachrecord["devops1"]: Creating...
alicloud_dns_record.eachrecord["devops2"]: Creating...
alicloud_dns_record.eachrecord["devops3"]: Creating...
alicloud_dns_record.eachrecord["devops2"]: Creation complete after 0s [id=843317481926367232]
alicloud_dns_record.eachrecord["devops3"]: Creation complete after 0s [id=843317481928446976]
alicloud_dns_record.eachrecord["devops1"]: Creation complete after 0s [id=843317481953598464]

Apply complete! Resources: 3 added, 0 changed, 0 destroyed.

删除 devops2 记录，重新执行

## for_each.tf

locals {
  zone = "evescn.com"
  # records = ["devops1", "devops2", "devops3"]
  records = ["devops1", "devops3"]
}

resource "alicloud_dns_record" "eachrecord" {
  for_each    = toset(local.records)
  name        = local.zone
  host_record = each.value
  type        = "A"
  value       = "192.168.1.1"
}

执行部署

evescn@evescndeMacBook-Pro for_each % terraform apply
alicloud_dns_record.eachrecord["devops2"]: Refreshing state... [id=843317481926367232]
alicloud_dns_record.eachrecord["devops3"]: Refreshing state... [id=843317481928446976]
alicloud_dns_record.eachrecord["devops1"]: Refreshing state... [id=843317481953598464]

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  - destroy

Terraform will perform the following actions:

  # alicloud_dns_record.eachrecord["devops2"] will be destroyed
  # (because key ["devops2"] is not in for_each map)
  - resource "alicloud_dns_record" "eachrecord" {
      - host_record = "devops2" -> null
      - id          = "843317481926367232" -> null
      - locked      = false -> null
      - name        = "evescn.com" -> null
      - priority    = 0 -> null
      - routing     = "default" -> null
      - status      = "ENABLE" -> null
      - ttl         = 600 -> null
      - type        = "A" -> null
      - value       = "192.168.1.1" -> null
    }

Plan: 0 to add, 0 to change, 1 to destroy.

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

alicloud_dns_record.eachrecord["devops2"]: Destroying... [id=843317481926367232]
alicloud_dns_record.eachrecord["devops2"]: Destruction complete after 0s

Apply complete! Resources: 0 added, 0 changed, 1 destroyed.

dynamic 动态的内联块

dynamic : 定义动态资源块，后面是 label， 默认为生成的语句块名称；
for_each : 要进行迭代循环的对象（map、list、set）;
iterator : 临时的变量名称，如果未定义则使用 label 即 ports ；
content : 要生成的语句块的内容部分；

dynamic "label" {
# 支持 map list set 等数据
for_each = map | list | set
iterator = iterator_name
content {
key = iterator_name.value
}
}

dynamic "ports" {
for_each = local.jenkins_ports
content {
internal = ports.value.internal
external = ports.value.external
ip = "0.0.0.0"
protocol = "tcp"
}
}

Docker 中的 ports{}

resource "docker_container" "jenkins" {

  ports {
    internal = 8080
    external = 8080
    ip       = "0.0.0.0"
    protocol = "tcp"
  }
  
  ports {
    internal = 50000
    external = 50000
    ip       = "0.0.0.0"
    protocol = "tcp"
  }
}

定义一个local变量；使用dynamic动态内联块

for_each遍历资源；ports.value引用遍历的资源

locals {
  jenkins_ports = [
    {
      internal = 8080
      external = 8080
    },
    {
      internal = 50000
      external = 50000
    }
  ]
}

resource "docker_container" "jenkins" {

  // 使用dynamic来实现动态
  dynamic "ports" {
    for_each = local.jenkins_ports
    content {
      internal = ports.value.internal
      external = ports.value.external
      ip       = "0.0.0.0"
      protocol = "tcp"
    }
  }

`depends_on` 依赖关系

处理资源或模块之间的依赖关系。

resource "docker_image" "jenkins" {
  name         = "jenkins/jenkins:2.332.2-centos7-jdk8"
  force_remove = false
  keep_locally = true
}


resource "docker_container" "jenkins" {
  image      = docker_image.jenkins.name
  name       = "jenkins-demo"

  # 依赖 docker_image 资源
  depends_on = [
    docker_image.jenkins
  ]
}

provider 自定义供应商

resource 覆盖资源中的 provider

例如：分别在 cn-beijing 和 cn-shanghai 区域分别创建1个实例。

provider "alicloud" {
  alias  = "north"
  region = "cn-beijing"
  access_key = "AKIR"
  secret_key = "MJy5JXmZn"
}

provider "alicloud" {
  region     = "cn-shanghai"
  access_key = "AK5R"
  secret_key = "MJy5JX6HIqmZn"
}

resource "alicloud_instance" "ecs_demo_north" {
  provider      = alicloud.north
  ...
}

resource "alicloud_instance" "ecs_demo" {
  ...
}

module 默认子模块继承根模块的provider；

provider = map()
key: provider名称
value: <provider>.<alias>

provider "alicloud" {
alias = "north"
region = "cn-beijing"
}

provider "alicloud" {
region = "cn-shanghai"
}

module "example" {
source = "./example"
# module 中的 provider 配置
providers = {
alicloud = alicloud.north
}
}

lifecycle 生命周期

标记资源不被删除或者销毁前创建新的资源；

lifecycle {
  xxx
}

create_before_destroy 先创建新的对象，再销毁旧的对象；
prevent_destroy 防止资源被销毁；
ignore_changes 忽略资源的差异；
replace_triggered_by 当指定的资源修改后替换当前资源；
precondition postcondition 条件检查

lifecycle {
create_before_destroy = true
# prevent_destroy = true
ignore_changes = [
tags, instance_name
]
replace_triggered_by = [
alicloud_vpc.vpc.vpc_name
]
}

Terraform 扩展

Terraform 扩展

Terraform Meta-Arguments 元参数

Count 创建资源副本

Terraform 配置

创建 DNS 解析

for_each 创建资源副本

Terraform 配置

创建 DNS 解析

dynamic 动态的内联块

depends_on 依赖关系

provider 自定义供应商

lifecycle 生命周期

`Terraform` `Meta-Arguments` 元参数

`Count` 创建资源副本

`Terraform` 配置

`for_each` 创建资源副本

`Terraform` 配置

`depends_on` 依赖关系