resource/aws_ecs_task_definition: prevent spurious container definition diffs

[ilkansh8]

Description

When the order of the container definitions does not match between AWS API and aws_ecs_task_definition, terraform tries to replace the task definition to match the container definitions order. This is unnecessary as the container order does not mean anything.

I am trying to to import bunch of different task definitions using a single module, and I keep getting diffs due to container definitions order. This PR prevents unnecessary diffs for when the container definitions order does not match between API and Terraform.

resource "aws_ecs_task_definition" "test" {
    family = "testtaskdef1"
    container_definitions = jsonencode([
        {
            "name": "sidecard",
            "image": "sidecar:1",
            "cpu": 0,
            "portMappings": [],
            "essential": false,
            "environment": [
                {
                    "name": "sidecarenv",
                    "value": "sidecarenvvalue"
                },
                {
                    "name": "sidecarenv2",
                    "value": "sidecarenvvalue"
                }
            ],
            "environmentFiles": [],
            "mountPoints": [],
            "volumesFrom": [],
            "systemControls": []
        },
        {
            "name": "app",
            "image": "busybox:1",
            "cpu": 0,
            "portMappings": [
                {
                    "name": "app-80-tcp",
                    "containerPort": 80,
                    "hostPort": 80,
                    "protocol": "tcp",
                    "appProtocol": "http"
                }
            ],
            "essential": true,
            "environment": [
                {
                    "name": "appenv",
                    "value": "appenvvalue"
                }
            ],
            "environmentFiles": [],
            "mountPoints": [],
            "volumesFrom": [],
            "ulimits": [],
            "systemControls": []
        }
      ])
}

  # aws_ecs_task_definition.test must be replaced
  # (imported from "arn:aws:ecs:eu-central-1:zz:task-definition/testtaskdef1:2")
  # Warning: this will destroy the imported resource
-/+ resource "aws_ecs_task_definition" "test" {
      ~ arn                      = "arn:aws:ecs:eu-central-1:zz:task-definition/testtaskdef1:2" -> (known after apply)
      ~ arn_without_revision     = "arn:aws:ecs:eu-central-1:zz:task-definition/testtaskdef1" -> (known after apply)
      ~ container_definitions    = jsonencode(
          ~ [
              - {
                  - cpu              = 0
                  - environment      = [
                      - {
                          - name  = "appenv"
                          - value = "appenvvalue"
                        },
                    ]
                  - environmentFiles = []
                  - essential        = true
                  - image            = "busybox:1"
                  - mountPoints      = []
                  - name             = "app"
                  - portMappings     = [
                      - {
                          - appProtocol   = "http"
                          - containerPort = 80
                          - hostPort      = 80
                          - name          = "app-80-tcp"
                          - protocol      = "tcp"
                        },
                    ]
                  - systemControls   = []
                  - ulimits          = []
                  - volumesFrom      = []
                },
                {
                    cpu              = 0
                    environment      = [
                        {
                            name  = "sidecarenv"
                            value = "sidecarenvvalue"
                        },
                    ]
                    environmentFiles = []
                    essential        = false
                    image            = "sidecar:1"
                    mountPoints      = []
                    name             = "sidecard"
                    portMappings     = []
                    systemControls   = []
                    volumesFrom      = []
                },
              + {
                  + cpu              = 0
                  + environment      = [
                      + {
                          + name  = "appenv"
                          + value = "appenvvalue"
                        },
                    ]
                  + environmentFiles = []
                  + essential        = true
                  + image            = "busybox:1"
                  + mountPoints      = []
                  + name             = "app"
                  + portMappings     = [
                      + {
                          + appProtocol   = "http"
                          + containerPort = 80
                          + hostPort      = 80
                          + name          = "app-80-tcp"
                          + protocol      = "tcp"
                        },
                    ]
                  + systemControls   = []
                  + ulimits          = []
                  + volumesFrom      = []
                },
            ] # forces replacement
        )

Relations

Relates #11463.
Relates #35792.

[github-actions]

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[ewbankkit]

LGTM 🚀.

% make testacc TESTARGS='-run=TestAccECSTaskDefinition_basic' PKG=ecs
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./internal/service/ecs/... -v -count 1 -parallel 20  -run=TestAccECSTaskDefinition_basic -timeout 360m
=== RUN   TestAccECSTaskDefinition_basic
=== PAUSE TestAccECSTaskDefinition_basic
=== CONT  TestAccECSTaskDefinition_basic
--- PASS: TestAccECSTaskDefinition_basic (30.80s)
PASS
ok  	github.com/hashicorp/terraform-provider-aws/internal/service/ecs	38.830s

[ewbankkit]

@ilkansh8 Thanks for the contribution 🎉 👏.

[github-actions]

This functionality has been released in v5.39.0 of the Terraform AWS Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

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