Add support for S3 as a DMS target endpoint

[microamp]

This is a port of #1685 by @altay13 with suggested changes from the pull request. (The PR hasn't been active lately and had many conflicts to resolve, so I decided to work on it. Hope I'm not stepping on someone's toes.)

Notes:

• bucket_name and bucket_folder were removed from the top-level attribute namespace. They are now available under s3_settings. This is consistent with how the MongoDB endpoint is implemented which follows the convention as seen in the output of aws dms create-endpoint --generate-cli-skeleton (see below).

{
  ...
  "DynamoDbSettings": {
    "ServiceAccessRoleArn": "",
  },
  "S3Settings": {
    "ServiceAccessRoleArn": "",
    "ExternalTableDefinition": "",
    "CsvRowDelimiter": "",
    "CsvDelimiter": "",
    "BucketFolder": "",
    "BucketName": "",
    "CompressionType": "none"
  },
  "MongoDbSettings": {
    ...
  }
}

• The existing service_access_role attribute shouldn't be reused as there is now service_access_role_arn under s3_settings. I suggest moving service_access_role to dynamodb_settings (currently missing) in the future and remove it from the top-level namespace.
• Helper functions (dmsEndpointTargetUpdateConfig and dmsEndpointTargetUpdateConfigUpdate) were removed from the test suite, to keep each endpoint test completely independent of each other despite some repetitions in the config strings.
• Conflicts were resolved in the merge commit below in order to keep the original work alive (instead of rebased).
• This PR is for target endpoint only. Currently, dms.S3Settings provides fields for target endpoint only. See https://github.com/microamp/terraform-provider-aws/blob/dms-target-endpoint-s3/vendor/github.com/aws/aws-sdk-go/service/databasemigrationservice/api.go#L10558-L10587 for more details.
  • Setting up source endpoint attributes is possible via extra_connection_attributes, but that has not been tested as part of this work.
• All acceptance tests for DMS endpoint continue to pass.

$ make testacc TEST=./aws TESTARGS='-run=TestAccAwsDmsEndpoint'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -run=TestAccAwsDmsEndpoint -timeout 120m
=== RUN   TestAccAwsDmsEndpointBasic
--- PASS: TestAccAwsDmsEndpointBasic (65.44s)
=== RUN   TestAccAwsDmsEndpointS3
--- PASS: TestAccAwsDmsEndpointS3 (143.07s)
=== RUN   TestAccAwsDmsEndpointDynamoDb
--- PASS: TestAccAwsDmsEndpointDynamoDb (79.62s)
=== RUN   TestAccAwsDmsEndpointMongoDb
--- PASS: TestAccAwsDmsEndpointMongoDb (60.60s)
PASS
ok     github.com/microamp/terraform-provider-aws/aws 348.744s

Thanks, please let me know if I missed anything.

[bflad]

Pulling this in -- thanks for @altay13 and @microamp for their work here 🚀

4 tests passed (all tests)
=== RUN   TestAccAwsDmsEndpointBasic
--- PASS: TestAccAwsDmsEndpointBasic (13.15s)
=== RUN   TestAccAwsDmsEndpointMongoDb
--- PASS: TestAccAwsDmsEndpointMongoDb (13.14s)
=== RUN   TestAccAwsDmsEndpointDynamoDb
--- PASS: TestAccAwsDmsEndpointDynamoDb (34.96s)
=== RUN   TestAccAwsDmsEndpointS3
--- PASS: TestAccAwsDmsEndpointS3 (35.02s)

[bflad]

This has been released in version 1.18.0 of the AWS provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!