循环小部件部分

Question

如何仅迭代地形脚本的小部件部分并在单个仪表板中获取所有小部件？

locals {
  instances = csvdecode(file("${path.module}/sample.csv"))
}

如果我们使用 count，它将循环这部分

resource "aws_cloudwatch_dashboard" "main" {
  dashboard_name = "my-dashboard" 
  dashboard_body = <<EOF
 { 
   "widgets": [
       {
          "type":"metric",
          "x":0,
          "y":0,
          "width":12,
          "height":6,  
          "properties":{
             "metrics":[ 
              for itr in local.instances.id:
                [
                   "AWS/EC2",
                   "CPUUtilization",
                   "InstanceId",
                   itr   // want this section to fetch the value form excel 
                ]
             ],
             "period":300,
             "stat":"Average",
             "region":"ap-south-1",
             "title":"EC2 Instance CPU ",
             "annotations": {
                "horizontal": [
                      {
                         "label": "Untitled annotation",
                         "value": 2
                     }]}
          }},]}EOF}

Answer 1

如果您的目标是生成 JSON，通常最好使用 jsonencode 而不是 template_file ，因为它可以自动处理 JSON 语法细节，从而避免需要调整文本模板的烦人细节来获得正确的 JSON。

例如：

dashboard_body = jsonencode({
  "widgets": [
    "type": "metric",
    "x": 0,
    "y": 0,
    "width": 12,
    "height": 6,
    "properties": {
      "metrics": [
        for inst in local.instances : [
          "AWS/EC2",
          "CPUUtilization",
          "InstanceId",
          inst.id,
        ]
      ],
      "period": 300,
      # etc, etc
    },
  ],
})

通过使用jsonencode您可以使用 Terraform 的任何正常语言功能和函数来生成数据结构，并让 jsonencode 函数在最后将其转换为有效的 JSON 语法。

Answer 2

我尝试使用两个template_file资源。

样品.csv用于测试

instance_id
i-00001
i-00002
i-00003

1. 为循环创建一个template_file资源，

data "template_file" "ec2_metric" {
  count    = length(local.instances)
  template = jsonencode([ "AWS/EC2", "CPUUtilization", "InstanceId", element(local.instances.*.instance_id, count.index)])
}

2. 为整个 JSON 创建template_file

data "template_file" "widgets" {
  template = <<JSON
  { 
   "widgets": [
       {
          "type":"metric",
          "x":0,
          "y":0,
          "width":12,
          "height":6,  
          "properties":{
             "metrics":[ 
               ${join(", n               ", data.template_file.ec2_metric.*.rendered)}
             ],
             "period":300,
             "stat":"Average",
             "region":"ap-south-1",
             "title":"EC2 Instance CPU ",
             "annotations": {
                "horizontal": [
                      {
                         "label": "Untitled annotation",
                         "value": 2
                     }]}
          }},]}
JSON
}

3. 使用template_file，

resource "aws_cloudwatch_dashboard" "main" {
  dashboard_name = "my-dashboard" 
  dashboard_body = data.template_file.widgets.rendered
...
}

4. 测试template_file.小部件

output "test" {
  value = data.template_file.widgets.rendered
}

结果

Outputs:
test =   { 
   "widgets": [
       {
          "type":"metric",
          "x":0,
          "y":0,
          "width":12,
          "height":6,  
          "properties":{
             "metrics":[ 
               ["AWS/EC2","CPUUtilization","InstanceId","i-00001"], 
               ["AWS/EC2","CPUUtilization","InstanceId","i-00002"], 
               ["AWS/EC2","CPUUtilization","InstanceId","i-00003"]
             ],
             "period":300,
             "stat":"Average",
             "region":"ap-south-1",
             "title":"EC2 Instance CPU ",
             "annotations": {
                "horizontal": [
                      {
                         "label": "Untitled annotation",
                         "value": 2
                     }]}
          }},]}