Terraform 扩展

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
countresource 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_eachresource modulefor_each 它只能用于set(string) 或者map(string)
depends_onresource module处理 Terraform 无法自动推断的资源或模块之间的依赖关系
providerresource 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
lifecycleresource 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

  • devops1.evescn.com
  • devops2.evescn.com
  • devops3.evescn.com
Terraform 配置
## count.tflocals {zone = "evescn.com"records = ["devops1","devops2","devops3"]
}resource "alicloud_dns_record" "record" {count = length(local.records)name        = local.zonehost_record = local.records[count.index]type        = "A"value       = "192.168.1.1"
}
## count.tflocals {zone = "evescn.com"records = ["devops1","devops2","devops3"]
}resource "alicloud_dns_record" "record" {count = length(local.records)name        = local.zonehost_record = local.records[count.index]type        = "A"value       = "192.168.1.1"
}
创建 DNS 解析
evescn@evescndeMacBook-Pro count % terraform initInitializing 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.tfevescn@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:+ createTerraform 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-approveTerraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:+ createTerraform 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.zonehost_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- destroyTerraform 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- destroyTerraform 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

  • devops1.evescn.com
  • devops2.evescn.com
  • devops3.evescn.com
Terraform 配置
## version.tfterraform {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.tflocals {zone = "evescn.com"# records = ["devops1", "devops2", "devops3"]records = ["devops1", "devops3"]
}resource "alicloud_dns_record" "eachrecord" {for_each    = toset(local.records)name        = local.zonehost_record = each.valuetype        = "A"value       = "192.168.1.1"
}
创建 DNS 解析
evescn@evescndeMacBook-Pro for_each % terraform initInitializing 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.tfevescn@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:+ createTerraform 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: yesalicloud_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.tflocals {zone = "evescn.com"# records = ["devops1", "devops2", "devops3"]records = ["devops1", "devops3"]
}resource "alicloud_dns_record" "eachrecord" {for_each    = toset(local.records)name        = local.zonehost_record = each.valuetype        = "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:- destroyTerraform 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: yesalicloud_dns_record.eachrecord["devops2"]: Destroying... [id=843317481926367232]
alicloud_dns_record.eachrecord["devops2"]: Destruction complete after 0sApply 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_namecontent {key = iterator_name.value}
}
dynamic "ports" {for_each = local.jenkins_portscontent {internal = ports.value.internalexternal = ports.value.externalip       = "0.0.0.0"protocol = "tcp"}
}

Docker 中的 ports{}

resource "docker_container" "jenkins" {ports {internal = 8080external = 8080ip       = "0.0.0.0"protocol = "tcp"}ports {internal = 50000external = 50000ip       = "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 = 8080external = 8080},{internal = 50000external = 50000}]
}resource "docker_container" "jenkins" {// 使用dynamic来实现动态dynamic "ports" {for_each = local.jenkins_portscontent {internal = ports.value.internalexternal = ports.value.externalip       = "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 = falsekeep_locally = true
}resource "docker_container" "jenkins" {image      = docker_image.jenkins.namename       = "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 = trueignore_changes = [tags, instance_name]replace_triggered_by = [alicloud_vpc.vpc.vpc_name]
}

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