Fix RDS instance bug where switching to IO2 from GP needs the allocated storage set

[nhenjes]

Description

When creating an RDS instance, the Allocated Storage param is passed correctly to AWS. When going from, for example, GP3 to IO2 on an existing instance only a change in the Storage Type is detected by the provider and only Storage Type is passed. AWS' API however, requires that both storage type and Allocated Storage are submitted as part of the request

Relations

Closes #36648.
Relates (closes?) #28589.

References

When running aws rds modify-db-instance --db-instance-identifier <db-name> --storage-type io2 --iops 3000 the following error is thrown

An error occurred (InvalidParameterCombination) when calling the ModifyDBInstance operation: You must specify both the storage size and iops when modifying the storage size or iops on a DB instance that has iops.

When running aws rds modify-db-instance --db-instance-identifier <db-name> --storage-type io2 --iops 3000 --allocated-storage 100

The result is a successful change

Subsequent runs with the same params result in success meaning passing the allocated storage again is perfectly fine

Output from Acceptance Testing

==> Checking that code complies with gofmt requirements...
TF_ACC=1 go1.22.2 test ./internal/service/rds/... -v -count 1 -parallel 20 -run='TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops'  -timeout 360m
=== RUN   TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops
=== PAUSE TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops
=== CONT  TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops
--- PASS: TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops (970.05s)
PASS
ok  	github.com/hashicorp/terraform-provider-aws/internal/service/rds	976.063s

[github-actions]

Community Note

Voting for Prioritization

• Please vote on this pull request by adding a 👍 reaction to the original post to help the community and maintainers prioritize this pull request.
• Please see our prioritization guide for information on how we prioritize.
• Please do not leave "+1" or other comments that do not add relevant new information or questions, they generate extra noise for issue followers and do not help prioritize the request.

For Submitters

• Review the contribution guide relating to the type of change you are making to ensure all of the necessary steps have been taken.
• For new resources and data sources, use skaff to generate scaffolding with comments detailing common expectations.
• Whether or not the branch has been rebased will not impact prioritization, but doing so is always a welcome surprise.

[github-actions]

Welcome @nhenjes 👋

It looks like this is your first Pull Request submission to the Terraform AWS Provider! If you haven’t already done so please make sure you have checked out our CONTRIBUTOR guide and FAQ to make sure your contribution is adhering to best practice and has all the necessary elements in place for a successful approval.

Also take a look at our FAQ which details how we prioritize Pull Requests for inclusion.

Thanks again, and welcome to the community! 😃

[DrFaust92]

nhenjes Thank you for your contribution, can you also add a test for this?

[nhenjes]

@DrFaust92 I can work on writing a test for this

[nhenjes]

@DrFaust92 I was able to get my test working properly now. The test will provision a cluster using GP3 at 400GB with 12000 provisioned IOPs then updates to IO2 successfully.

Without the bug fix, the same test reports

        Error: updating RDS DB Instance (terraform-20240517150000387300000001): operation error RDS: ModifyDBInstance, https response error StatusCode: 400, RequestID: b15c2fa4-e202-4778-a85f-09f34ce77dcc, api error InvalidParameterCombination: You must specify both the storage size and iops when modifying the storage size or iops on a DB instance that has iops.
        
          with aws_db_instance.test,
          on terraform_plugin_test.tf line 56, in resource "aws_db_instance" "test":
          56: resource "aws_db_instance" "test" {

[YakDriver]

Looks good 🎉

% make t T=TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops K=rds
make: go1.23.3 not found
make: installing go1.23.3...
make: if you get an error, see https://go.dev/doc/manage-install to locally install various Go versions
go: downloading golang.org/dl v0.0.0-20241106222207-4e0968199959
Downloaded   0.0% (   16384 / 71639942 bytes) ...
Downloaded  17.8% (12763072 / 71639942 bytes) ...
Downloaded 100.0% (71639942 / 71639942 bytes)
Unpacking /Users/dirk/sdk/go1.23.3/go1.23.3.darwin-arm64.tar.gz ...
Success. You may now run 'go1.23.3'
make: go1.23.3 ready
make: Verifying source code with gofmt...
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go1.23.3 test ./internal/service/rds/... -v -count 1 -parallel 20 -run='TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops'  -timeout 360m
go: downloading github.com/aws/aws-sdk-go-v2/service/apigateway v1.28.0
go: downloading github.com/aws/aws-sdk-go-v2/service/applicationautoscaling v1.34.0
go: downloading github.com/aws/aws-sdk-go-v2/service/appsync v1.40.0
go: downloading github.com/aws/aws-sdk-go-v2/service/cloudfront v1.43.0
go: downloading github.com/aws/aws-sdk-go-v2/service/cloudtrail v1.46.0
go: downloading github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs v1.44.0
go: downloading github.com/aws/aws-sdk-go-v2/service/costexplorer v1.44.0
go: downloading github.com/aws/aws-sdk-go-v2/service/dlm v1.28.7
go: downloading github.com/aws/aws-sdk-go-v2/service/ec2 v1.193.0
go: downloading github.com/aws/aws-sdk-go-v2/service/elasticache v1.44.0
go: downloading github.com/aws/aws-sdk-go-v2/service/elasticloadbalancingv2 v1.42.1
go: downloading github.com/aws/aws-sdk-go-v2/service/iot v1.61.0
go: downloading github.com/aws/aws-sdk-go-v2/service/lambda v1.68.0
go: downloading github.com/aws/aws-sdk-go-v2/service/polly v1.45.7
go: downloading github.com/aws/aws-sdk-go-v2/service/resiliencehub v1.28.0
go: downloading github.com/aws/aws-sdk-go-v2/service/s3 v1.68.0
go: downloading github.com/aws/aws-sdk-go-v2/service/ssm v1.56.0
go: downloading github.com/aws/aws-sdk-go-v2/service/ssmquicksetup v1.3.0
go: downloading github.com/aws/aws-sdk-go-v2/service/xray v1.30.0
go: downloading github.com/aws/aws-sdk-go-v2/feature/s3/manager v1.17.40
2024/11/22 09:58:11 Initializing Terraform AWS Provider...
=== RUN   TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops
=== PAUSE TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops
=== CONT  TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops
--- PASS: TestAccRDSCluster_storageTypeGeneralPurposeToProvisionedIops (1084.15s)
PASS
ok  	github.com/hashicorp/terraform-provider-aws/internal/service/rds	1088.267s

[johnsonaj]

LGTM 🚀

[github-actions]

This functionality has been released in v5.78.0 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]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.
If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.