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Contributing to Terraform - AWS Provider

First: if you're unsure or afraid of anything, just ask or submit the issue or pull request anyways. You won't be yelled at for giving your best effort. The worst that can happen is that you'll be politely asked to change something. We appreciate any sort of contributions, and don't want a wall of rules to get in the way of that.

However, for those individuals who want a bit more guidance on the best way to contribute to the project, read on. This document will cover what we're looking for. By addressing all the points we're looking for, it raises the chances we can quickly merge or address your contributions.

Specifically, we have provided checklists below for each type of issue and pull request that can happen on the project. These checklists represent everything we need to be able to review and respond quickly.

HashiCorp vs. Community Providers

We separate providers out into what we call "HashiCorp Providers" and "Community Providers".

HashiCorp providers are providers that we'll dedicate full time resources to improving, supporting the latest features, and fixing bugs. These are providers we understand deeply and are confident we have the resources to manage ourselves.

Community providers are providers where we depend on the community to contribute fixes and enhancements to improve. HashiCorp will run automated tests and ensure these providers continue to work, but will not dedicate full time resources to add new features to these providers. These providers are available in official Terraform releases, but the functionality is primarily contributed.

The current list of HashiCorp Providers is as follows:

  • aws
  • azurerm
  • google
  • opc

Our testing standards are the same for both HashiCorp and Community providers, and HashiCorp runs full acceptance test suites for every provider nightly to ensure Terraform remains stable.

We make the distinction between these two types of providers to help highlight the vast amounts of community effort that goes in to making Terraform great, and to help contributors better understand the role HashiCorp employees play in the various areas of the code base.

Issues

Issue Reporting Checklists

We welcome issues of all kinds including feature requests, bug reports, and general questions. Below you'll find checklists with guidelines for well-formed issues of each type.

Bug Reports

  • Test against latest release: Make sure you test against the latest released version. It is possible we already fixed the bug you're experiencing.

  • Search for possible duplicate reports: It's helpful to keep bug reports consolidated to one thread, so do a quick search on existing bug reports to check if anybody else has reported the same thing. You can scope searches by the label "bug" to help narrow things down.

  • Include steps to reproduce: Provide steps to reproduce the issue, along with your .tf files, with secrets removed, so we can try to reproduce it. Without this, it makes it much harder to fix the issue.

  • For panics, include crash.log: If you experienced a panic, please create a gist of the entire generated crash log for us to look at. Double check no sensitive items were in the log.

Feature Requests

  • Search for possible duplicate requests: It's helpful to keep requests consolidated to one thread, so do a quick search on existing requests to check if anybody else has reported the same thing. You can scope searches by the label "enhancement" to help narrow things down.

  • Include a use case description: In addition to describing the behavior of the feature you'd like to see added, it's helpful to also lay out the reason why the feature would be important and how it would benefit Terraform users.

Questions

  • Search for answers in Terraform documentation: We're happy to answer questions in GitHub Issues, but it helps reduce issue churn and maintainer workload if you work to find answers to common questions in the documentation. Often times Question issues result in documentation updates to help future users, so if you don't find an answer, you can give us pointers for where you'd expect to see it in the docs.

Issue Lifecycle

  1. The issue is reported.

  2. The issue is verified and categorized by a Terraform collaborator. Categorization is done via GitHub labels. We generally use a two-label system of (1) issue/PR type, and (2) section of the codebase. Type is usually "bug", "enhancement", "documentation", or "question", and section can be any of the providers or provisioners or "core".

  3. Unless it is critical, the issue is left for a period of time (sometimes many weeks), giving outside contributors a chance to address the issue.

  4. The issue is addressed in a pull request or commit. The issue will be referenced in the commit message so that the code that fixes it is clearly linked.

  5. The issue is closed. Sometimes, valid issues will be closed to keep the issue tracker clean. The issue is still indexed and available for future viewers, or can be re-opened if necessary.

Pull Requests

Thank you for contributing! Here you'll find information on what to include in your Pull Request to ensure it is accepted quickly.

  • For pull requests that follow the guidelines, we expect to be able to review and merge very quickly.
  • Pull requests that don't follow the guidelines will be annotated with what they're missing. A community or core team member may be able to swing around and help finish up the work, but these PRs will generally hang out much longer until they can be completed and merged.

Pull Request Lifecycle

  1. You are welcome to submit your pull request for commentary or review before it is fully completed. Please prefix the title of your pull request with "[WIP]" to indicate this. It's also a good idea to include specific questions or items you'd like feedback on.

  2. Once you believe your pull request is ready to be merged, you can remove any "[WIP]" prefix from the title and a core team member will review. Follow the checklists below to help ensure that your contribution will be merged quickly.

  3. One of Terraform's core team members will look over your contribution and either provide comments letting you know if there is anything left to do. We do our best to provide feedback in a timely manner, but it may take some time for us to respond.

  4. Once all outstanding comments and checklist items have been addressed, your contribution will be merged! Merged PRs will be included in the next Terraform release. The core team takes care of updating the CHANGELOG as they merge.

  5. In rare cases, we might decide that a PR should be closed. We'll make sure to provide clear reasoning when this happens.

Checklists for Contribution

There are several different kinds of contribution, each of which has its own standards for a speedy review. The following sections describe guidelines for each type of contribution.

Documentation Update

Because Terraform's website is in the same repo as the code, it's easy for anybody to help us improve our docs.

  • Reasoning for docs update: Including a quick explanation for why the update needed is helpful for reviewers.
  • Relevant Terraform version: Is this update worth deploying to the site immediately, or is it referencing an upcoming version of Terraform and should get pushed out with the next release?

Enhancement/Bugfix to a Resource

Working on existing resources is a great way to get started as a Terraform contributor because you can work within existing code and tests to get a feel for what to do.

  • Acceptance test coverage of new behavior: Existing resources each have a set of acceptance tests covering their functionality. These tests should exercise all the behavior of the resource. Whether you are adding something or fixing a bug, the idea is to have an acceptance test that fails if your code were to be removed. Sometimes it is sufficient to "enhance" an existing test by adding an assertion or tweaking the config that is used, but often a new test is better to add. You can copy/paste an existing test and follow the conventions you see there, modifying the test to exercise the behavior of your code.
  • Documentation updates: If your code makes any changes that need to be documented, you should include those doc updates in the same PR. The Terraform website source is in this repo and includes instructions for getting a local copy of the site up and running if you'd like to preview your changes.
  • Well-formed Code: Do your best to follow existing conventions you see in the codebase, and ensure your code is formatted with go fmt. (The Travis CI build will fail if go fmt has not been run on incoming code.) The PR reviewers can help out on this front, and may provide comments with suggestions on how to improve the code.
  • Vendor additions: Create a separate PR if you are updating the vendor folder. This is to avoid conflicts as the vendor versions tend to be fast moving targets.

New Resource

Implementing a new resource is a good way to learn more about how Terraform interacts with upstream APIs. There are plenty of examples to draw from in the existing resources, but you still get to implement something completely new.

  • Minimal LOC: It can be inefficient for both the reviewer and author to go through long feedback cycles on a big PR with many resources. We therefore encourage you to only submit 1 resource at a time.
  • Acceptance tests: New resources should include acceptance tests covering their behavior. See Writing Acceptance Tests below for a detailed guide on how to approach these.
  • Naming: Resources should be named aws_<service>_<name> where service is the AWS short service name and name is a short, preferably single word, description of the resource. Use _ as a separator.
  • Arguments_and_Attributes: The HCL for arguments and attributes should mimic the types and structs presented by the AWS API. API arguments should be converted from CamelCase to camel_case.
  • Documentation: Each resource gets a page in the Terraform documentation. The Terraform website source is in this repo and includes instructions for getting a local copy of the site up and running if you'd like to preview your changes. For a resource, you'll want to add a new file in the appropriate place and add a link to the sidebar for that page.
  • Well-formed Code: Do your best to follow existing conventions you see in the codebase, and ensure your code is formatted with go fmt. (The Travis CI build will fail if go fmt has not been run on incoming code.) The PR reviewers can help out on this front, and may provide comments with suggestions on how to improve the code.
  • Vendor updates: Create a separate PR if you are adding to the vendor folder. This is to avoid conflicts as the vendor versions tend to be fast moving targets.

New Service

Implementing a new AWS service gives Terraform the ability to manage resources in a whole new API. It's a larger undertaking, but brings major new functionality into Terraform.

  • Service Client: Before new resources are submitted, we encourage a separate pull request containing just the new AWS Go SDK service client. Doing so will pull in the AWS Go SDK service code into the project at the current version. Since the AWS Go SDK is updated frequently, these pull requests can easily have merge conflicts or be out of date. The maintainers prioritize reviewing and merging these quickly to prevent those situations.

    To add the AWS Go SDK service client:

    • In aws/provider.go Add a new service entry to endpointServiceNames. This service name should match the AWS Go SDK or AWS CLI service name.
    • In aws/config.go: Add a new import for the AWS Go SDK code. e.g. github.com/aws/aws-sdk-go/service/quicksight
    • In aws/config.go: Add a new {SERVICE}conn field to the AWSClient struct for the service client. The service name should match the name in endpointServiceNames. e.g. quicksightconn *quicksight.QuickSight
    • In aws/config.go: Create the new service client in the {SERVICE}conn field in the AWSClient instantiation within Client(). e.g. quicksightconn: quicksight.New(sess.Copy(&aws.Config{Endpoint: aws.String(c.Endpoints["quicksight"])})),
    • In website/docs/guides/custom-service-endpoints.html.md: Add the service name in the list of customizable endpoints.
    • Run the following then submit the pull request:
    go test ./aws
    go mod tidy
    go mod vendor
  • Initial Resource: Some services may be big and it can be inefficient for both reviewer & author to go through long feedback cycles on a big PR with many resources. Often feedback items in one resource will also need to be applied in other resources. We encourage you to submit the necessary minimum in a single PR, ideally just the first resource of the service.

The initial resource and changes afterwards should follow the other sections of this guide as appropriate.

New Region

While region validation is automatically added with SDK updates, new regions are generally limited in which services they support. Below are some manually sourced values from documentation.

Terraform Schema and Code Idiosyncracies

There are aspects of the terraform code base and models which have a common theme and style

  • Ignore Timestamps: Generally, creation and modification dates are not included in schemas.
  • Attribute Update Tests: Try to add a second test step in at least one test case showing attribute changes propagate during Update operations
  • AWS Errors: Use the helper function (isAWSErr(err, ...)) to check the type of AWS error.
  • Computed: The Computed attribute is generally used in isolation for any IDs or anything not defined in the config and returned by the API.
  • Computed with Optional: The Computed attribute is generally used in conjunction with Optional when the API automatically sets unpredictable default value or when the value is generally not static and depends on other attributes.
  • Spelling: When referencing resources in the AWS API, use spelling which matches that of official AWS documentation. In all other cases, use American spelling for variables, functions, and constants.
  • Removed Resources: If a resource is removed from AWS outside of Terraform (e.g. via different tool, API or web UI), make sure to catch this case. Print a [WARN] log message, and use d.SetId("") to remove the resource from state inside Read().

Writing Acceptance Tests

Terraform includes an acceptance test harness that does most of the repetitive work involved in testing a resource. For additional information about testing Terraform Providers, see the Extending Terraform documentation.

Acceptance Tests Often Cost Money to Run

Because acceptance tests create real resources, they often cost money to run. Because the resources only exist for a short period of time, the total amount of money required is usually a relatively small. Nevertheless, we don't want financial limitations to be a barrier to contribution, so if you are unable to pay to run acceptance tests for your contribution, simply mention this in your pull request. We will happily accept "best effort" implementations of acceptance tests and run them for you on our side. This might mean that your PR takes a bit longer to merge, but it most definitely is not a blocker for contributions.

Running an Acceptance Test

Acceptance tests can be run using the testacc target in the Terraform Makefile. The individual tests to run can be controlled using a regular expression. Prior to running the tests provider configuration details such as access keys must be made available as environment variables.

For example, to run an acceptance test against the Amazon Web Services provider, the following environment variables must be set:

# Using a profile
export AWS_PROFILE=...
# Otherwise
export AWS_ACCESS_KEY_ID=...
export AWS_SECRET_ACCESS_KEY=...
export AWS_DEFAULT_REGION=...

Tests can then be run by specifying the target provider and a regular expression defining the tests to run:

$ make testacc TEST=./aws TESTARGS='-run=TestAccAWSCloudWatchDashboard_update'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -run=TestAccAWSCloudWatchDashboard_update -timeout 120m
=== RUN   TestAccAWSCloudWatchDashboard_update
--- PASS: TestAccAWSCloudWatchDashboard_update (26.56s)
PASS
ok  	github.com/terraform-providers/terraform-provider-aws/aws	26.607s

Entire resource test suites can be targeted by using the naming convention to write the regular expression. For example, to run all tests of the aws_cloudwatch_dashboard resource rather than just the update test, you can start testing like this:

$ make testacc TEST=./aws TESTARGS='-run=TestAccAWSCloudWatchDashboard'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -run=TestAccAWSCloudWatchDashboard -timeout 120m
=== RUN   TestAccAWSCloudWatchDashboard_importBasic
--- PASS: TestAccAWSCloudWatchDashboard_importBasic (15.06s)
=== RUN   TestAccAWSCloudWatchDashboard_basic
--- PASS: TestAccAWSCloudWatchDashboard_basic (12.70s)
=== RUN   TestAccAWSCloudWatchDashboard_update
--- PASS: TestAccAWSCloudWatchDashboard_update (27.81s)
PASS
ok  	github.com/terraform-providers/terraform-provider-aws/aws	55.619s

Writing an Acceptance Test

Terraform has a framework for writing acceptance tests which minimises the amount of boilerplate code necessary to use common testing patterns. The entry point to the framework is the resource.ParallelTest() function.

Tests are divided into TestSteps. Each TestStep proceeds by applying some Terraform configuration using the provider under test, and then verifying that results are as expected by making assertions using the provider API. It is common for a single test function to exercise both the creation of and updates to a single resource. Most tests follow a similar structure.

  1. Pre-flight checks are made to ensure that sufficient provider configuration is available to be able to proceed - for example in an acceptance test targeting AWS, AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY must be set prior to running acceptance tests. This is common to all tests exercising a single provider.

Each TestStep is defined in the call to resource.ParallelTest(). Most assertion functions are defined out of band with the tests. This keeps the tests readable, and allows reuse of assertion functions across different tests of the same type of resource. The definition of a complete test looks like this:

func TestAccAWSCloudWatchDashboard_basic(t *testing.T) {
	var dashboard cloudwatch.GetDashboardOutput
	rInt := acctest.RandInt()
	resource.ParallelTest(t, resource.TestCase{
		PreCheck:     func() { testAccPreCheck(t) },
		Providers:    testAccProviders,
		CheckDestroy: testAccCheckAWSCloudWatchDashboardDestroy,
		Steps: []resource.TestStep{
			{
				Config: testAccAWSCloudWatchDashboardConfig(rInt),
				Check: resource.ComposeTestCheckFunc(
					testAccCheckCloudWatchDashboardExists("aws_cloudwatch_dashboard.foobar", &dashboard),
					resource.TestCheckResourceAttr("aws_cloudwatch_dashboard.foobar", "dashboard_name", testAccAWSCloudWatchDashboardName(rInt)),
				),
			},
		},
	})
}

When executing the test, the following steps are taken for each TestStep:

  1. The Terraform configuration required for the test is applied. This is responsible for configuring the resource under test, and any dependencies it may have. For example, to test the aws_cloudwatch_dashboard resource, a valid configuration with the requisite fields is required. This results in configuration which looks like this:

    resource "aws_cloudwatch_dashboard" "foobar" {
      dashboard_name = "terraform-test-dashboard-%d"
      dashboard_body = <<EOF
      {
        "widgets": [{
          "type": "text",
          "x": 0,
          "y": 0,
          "width": 6,
          "height": 6,
          "properties": {
            "markdown": "Hi there from Terraform: CloudWatch"
          }
        }]
      }
      EOF
    }
  2. Assertions are run using the provider API. These use the provider API directly rather than asserting against the resource state. For example, to verify that the aws_cloudwatch_dashboard described above was created successfully, a test function like this is used:

    func testAccCheckCloudWatchDashboardExists(n string, dashboard *cloudwatch.GetDashboardOutput) resource.TestCheckFunc {
      return func(s *terraform.State) error {
        rs, ok := s.RootModule().Resources[n]
        if !ok {
          return fmt.Errorf("Not found: %s", n)
        }
    
        conn := testAccProvider.Meta().(*AWSClient).cloudwatchconn
        params := cloudwatch.GetDashboardInput{
          DashboardName: aws.String(rs.Primary.ID),
        }
    
        resp, err := conn.GetDashboard(&params)
        if err != nil {
          return err
        }
    
        *dashboard = *resp
    
        return nil
      }
    }

    Notice that the only information used from the Terraform state is the ID of the resource. For computed properties, we instead assert that the value saved in the Terraform state was the expected value if possible. The testing framework provides helper functions for several common types of check - for example:

    resource.TestCheckResourceAttr("aws_cloudwatch_dashboard.foobar", "dashboard_name", testAccAWSCloudWatchDashboardName(rInt)),
  3. The resources created by the test are destroyed. This step happens automatically, and is the equivalent of calling terraform destroy.

  4. Assertions are made against the provider API to verify that the resources have indeed been removed. If these checks fail, the test fails and reports "dangling resources". The code to ensure that the aws_cloudwatch_dashboard shown above has been destroyed looks like this:

    func testAccCheckAWSCloudWatchDashboardDestroy(s *terraform.State) error {
      conn := testAccProvider.Meta().(*AWSClient).cloudwatchconn
    
      for _, rs := range s.RootModule().Resources {
        if rs.Type != "aws_cloudwatch_dashboard" {
          continue
        }
    
        params := cloudwatch.GetDashboardInput{
          DashboardName: aws.String(rs.Primary.ID),
        }
    
        _, err := conn.GetDashboard(&params)
        if err == nil {
          return fmt.Errorf("Dashboard still exists: %s", rs.Primary.ID)
        }
        if !isCloudWatchDashboardNotFoundErr(err) {
          return err
        }
      }
    
      return nil
    }

    These functions usually test only for the resource directly under test.

Writing and running Cross-Account Acceptance Tests

When testing requires AWS infrastructure in a second AWS account, the below changes to the normal setup will allow the management or reference of resources and data sources across accounts:

  • In the PreCheck function, include testAccAlternateAccountPreCheck(t) to ensure a standardized set of information is required for cross-account testing credentials
  • Declare a providers variable at the top of the test function: var providers []*schema.Provider
  • Switch usage of Providers: testAccProviders to ProviderFactories: testAccProviderFactories(&providers)
  • Add testAccAlternateAccountProviderConfig() to the test configuration and use provider = "aws.alternate" for cross-account resources. The resource that is the focus of the acceptance test should not use the provider alias to simplify the testing setup.
  • For any TestStep that includes ImportState: true, add the Config that matches the previous TestStep Config

An example acceptance test implementation can be seen below:

func TestAccAwsExample_basic(t *testing.T) {
  var providers []*schema.Provider
  resourceName := "aws_example.test"

  resource.ParallelTest(t, resource.TestCase{
    PreCheck: func() {
      testAccPreCheck(t)
      testAccAlternateAccountPreCheck(t)
    },
    ProviderFactories: testAccProviderFactories(&providers),
    CheckDestroy:      testAccCheckAwsExampleDestroy,
    Steps: []resource.TestStep{
      {
        Config: testAccAwsExampleConfig(),
        Check: resource.ComposeTestCheckFunc(
          testAccCheckAwsExampleExists(resourceName),
          // ... additional checks ...
        ),
      },
      {
        Config:            testAccAwsExampleConfig(),
        ResourceName:      resourceName,
        ImportState:       true,
        ImportStateVerify: true,
      },
    },
  })
}

func testAccAwsExampleConfig() string {
  return testAccAlternateAccountProviderConfig() + fmt.Sprintf(`
# Cross account resources should be handled by the cross account provider.
# The standardized provider alias is aws.alternate as seen below.
resource "aws_cross_account_example" "test" {
  provider = "aws.alternate"

  # ... configuration ...
}

# The resource that is the focus of the testing should be handled by the default provider,
# which is automatically done by not specifying the provider configuration in the resource.
resource "aws_example" "test" {
  # ... configuration ...
}
`)
}

Searching for usage of testAccAlternateAccountPreCheck in the codebase will yield real world examples of this setup in action.

Running these acceptance tests is the same as before, except the following additional credential information is required:

# Using a profile
export AWS_ALTERNATE_PROFILE=...
# Otherwise
export AWS_ALTERNATE_ACCESS_KEY_ID=...
export AWS_ALTERNATE_SECRET_ACCESS_KEY=...

Acceptance Testing Guidelines

The Terraform AWS Provider follows common practices to ensure consistent and reliable testing across all resources in the project. While there may be older testing present that predates these guidelines, new submissions are generally expected to adhere to these items to maintain Terraform Provider quality. For any guidelines listed, contributors are encouraged to ask any questions and community reviewers are encouraged to provide review suggestions based on these guidelines to speed up the review and merge process.

The below are required items that will be noted during submission review and prevent immediate merging:

  • Implements CheckDestroy: Resource testing should include a CheckDestroy function (typically named testAccCheckAws{SERVICE}{RESOURCE}Destroy) that calls the API to verify that the Terraform resource has been deleted or disassociated as appropriate. More information about CheckDestroy functions can be found in the Extending Terraform TestCase documentation.
  • Implements Exists Check Function: Resource testing should include a TestCheckFunc function (typically named testAccCheckAws{SERVICE}{RESOURCE}Exists) that calls the API to verify that the Terraform resource has been created or associated as appropriate. Preferably, this function will also accept a pointer to an API object representing the Terraform resource from the API response that can be set for potential usage in later TestCheckFunc. More information about these functions can be found in the Extending Terraform Custom Check Functions documentation.
  • Excludes Provider Declarations: Test configurations should not include provider "aws" {...} declarations. If necessary, only the provider declarations in provider_test.go should be used for multiple account/region or otherwise specialized testing.
  • Passes in us-west-2 Region: Tests default to running in us-west-2 and at a minimum should pass in that region or include necessary PreCheck functions to skip the test when ran outside an expected environment.
  • Uses resource.ParallelTest: Tests should utilize resource.ParallelTest() instead of resource.Test() except where serialized testing is absolutely required.
  • Uses fmt.Sprintf(): Test configurations preferably should to be separated into their own functions (typically named testAccAws{SERVICE}{RESOURCE}Config{PURPOSE}) that call fmt.Sprintf() for variable injection or a string const for completely static configurations. Test configurations should avoid var or other variable injection functionality such as text/template.
  • Uses Randomized Infrastructure Naming: Test configurations that utilize resources where a unique name is required should generate a random name. Typically this is created via rName := acctest.RandomWithPrefix("tf-acc-test") in the acceptance test function before generating the configuration.

For resources that support import, the additional item below is required that will be noted during submission review and prevent immediate merging:

  • Implements ImportState Testing: Tests should include an additional TestStep configuration that verifies resource import via ImportState: true and ImportStateVerify: true. This TestStep should be added to all possible tests for the resource to ensure that all infrastructure configurations are properly imported into Terraform.

The below are style-based items that may be noted during review and are recommended for simplicity, consistency, and quality assurance:

  • Uses Builtin Check Functions: Tests should utilize already available check functions, e.g. resource.TestCheckResourceAttr(), to verify values in the Terraform state over creating custom TestCheckFunc. More information about these functions can be found in the Extending Terraform Builtin Check Functions documentation.
  • Uses TestCheckResoureAttrPair() for Data Sources: Tests should utilize resource.TestCheckResourceAttrPair() to verify values in the Terraform state for data sources attributes to compare them with their expected resource attributes.
  • Excludes Timeouts Configurations: Test configurations should not include timeouts {...} configuration blocks except for explicit testing of customizable timeouts (typically very short timeouts with ExpectError).
  • Implements Default and Zero Value Validation: The basic test for a resource (typically named TestAccAws{SERVICE}{RESOURCE}_basic) should utilize available check functions, e.g. resource.TestCheckResourceAttr(), to verify default and zero values in the Terraform state for all attributes. Empty/missing configuration blocks can be verified with resource.TestCheckResourceAttr(resourceName, "{ATTRIBUTE}.#", "0") and empty maps with resource.TestCheckResourceAttr(resourceName, "{ATTRIBUTE}.%", "0")

The below are location-based items that may be noted during review and are recommended for consistency with testing flexibility. Resource testing is expected to pass across multiple AWS environments supported by the Terraform AWS Provider (e.g. AWS Standard and AWS GovCloud (US)). Contributors are not expected or required to perform testing outside of AWS Standard, e.g. running only in the us-west-2 region is perfectly acceptable, however these are provided for reference:

  • Uses aws_ami Data Source: Any hardcoded AMI ID configuration, e.g. ami-12345678, should be replaced with the aws_ami data source pointing to an Amazon Linux image. A common pattern is a configuration like the below, which will likely be moved into a common configuration function in the future:

    data "aws_ami" "amzn-ami-minimal-hvm-ebs" {
      most_recent = true
      owners      = ["amazon"]
    
      filter {
        name = "name"
        values = ["amzn-ami-minimal-hvm-*"]
      }
      filter {
        name = "root-device-type"
        values = ["ebs"]
      }
    }
  • Uses aws_availability_zones Data Source: Any hardcoded AWS Availability Zone configuration, e.g. us-west-2a, should be replaced with the aws_availability_zones data source. A common pattern is declaring data "aws_availability_zones" "current" {} and referencing it via data.aws_availability_zones.current.names[0] or data.aws_availability_zones.current.names[count.index] in resources utilizing count.

  • Uses aws_region Data Source: Any hardcoded AWS Region configuration, e.g. us-west-2, should be replaced with the aws_region data source. A common pattern is declaring data "aws_region" "cname} and referencing it via data.aws_region.current.name

  • Uses aws_partition Data Source: Any hardcoded AWS Partition configuration, e.g. the aws in a arn:aws:SERVICE:REGION:ACCOUNT:RESOURCE ARN, should be replaced with the aws_partition data source. A common pattern is declaring data "aws_partition" "current" {} and referencing it via data.aws_partition.current.partition

  • Uses Builtin ARN Check Functions: Tests should utilize available ARN check functions, e.g. testAccMatchResourceAttrRegionalARN(), to validate ARN attribute values in the Terraform state over resource.TestCheckResourceAttrSet() and resource.TestMatchResourceAttr()

  • Uses testAccCheckResourceAttrAccountID(): Tests should utilize the available AWS Account ID check function, testAccCheckResourceAttrAccountID() to validate account ID attribute values in the Terraform state over resource.TestCheckResourceAttrSet() and resource.TestMatchResourceAttr()