aws_api_gateway_method_response Concurrency

[steve-gray]

When creating multiple method response codes that live beneath the same method, Terraform will typically fail due to concurrency/conflict errors on the AWS side. It appears that AWS (whilst not documented anywhere visible) is treating the api_gateway_method as the concurrency boundary.

Terraform Version

0.8.2

Affected Resource(s)

Please list the resources as a list, for example:

• aws_api_gateway_method_response

If this issue appears to affect multiple resources, it may be an issue with Terraform's core, so please mention this.

Expected Behavior

Multiple response codes should be created correctly for an API response

Actual Behavior

Fails with error such as

 aws_api_gateway_method_response.dummy_function_response1: Error creating API Gateway Method Response: ConflictException: Response already exists for this resource
	status code: 409, request id: 56acda62-e292-11e6-b56a-85b5b33b47bd
* aws_api_gateway_method_response.dummy_function_response3: Error creating API Gateway Method Response: ConflictException: Response already exists for this resource
	status code: 409, request id: 56ae3a9c-e292-11e6-8218-a9497181c142
* aws_api_gateway_method_response.http409: ConflictException: Unable to complete operation due to concurrent modification. Please try again later.
	status code: 409, request id: 56acb348-e292-11e6-8d8e-77f3e0ae3f54
* aws_api_gateway_method_response.http401: ConflictException: Unable to complete operation due to concurrent modification. Please try again later.
	status code: 409, request id: 56ac6527-e292-11e6-8d8e-77f3e0ae3f54
* aws_api_gateway_method_response.dummy_function_response2: Error creating API Gateway Method Response: ConflictException: Unable to complete operation due to concurrent modification. Please try again later.
	status code: 409, request id: 56ac65c5-e292-11e6-99f9-efaae93431b6

Steps to Reproduce

terraform apply where you have an API gateway operation with multiple (2+) HTTP response codes defined which are new and require creating. Subsequent attempts may work as individual responses get created, but will require many retries before the race conditions are not encountered.

[sebolabs]

terraform 0.8.7
I encountered the problem with ConflictException: Unable to complete operation due to concurrent modification. today, two occurrences in 5 minutes and after that it disappeared.
To be safe in the future I just added dependencies on those responses so that they are being created one by one. Hopefully it will help.

[gustavlasko]

Using terraform 0.9.4, I get the same issue. I attempted to use @sebolabs' workaround, but it seems that I still get the same error, so it appears that terraform doesn't always honor the depends_on.

[skehlet]

I made each method depend on the one before it, and that seemed to get me past the ConflictExceptions. 😕

[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 have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.