ECS Container definition permanent diff

[jonathanmyers]

Hello!

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Issue details

Past some length or number of elements, the ECS container definition string starts showing current state in an alphabetized format. If your container definition object is not alphabetized in your source code, this results in a persistent diff where every pulumi up results in a task recreation regardless of whether real changes are present.

Also past this length or number of elements, current state starts showing default elements that are not present in source, which also creates a diff. I had to write in empty properties for mountPoint and volumesFrom, and set essential and cpu to prevent the diff.

The lack of a pretty printed diff of this string in pulumi's preview makes this a bit labor intensive to diagnose--with a large number of elements the only practical way to find the problem is to copy the string out, remove escape characters, then pretty print and diff the strings elsewhere.

I'm guessing the underlying AWS api does this for convenience in the UI, but I think there are some options for making it behave better in pulumi.

Steps to reproduce

1. Create a long container definition object where elements are not alphabetized. Mine is 5800 characters.
2. Run pulumi up twice and see that there is still a diff.

Expected: There is no diff after a successful pulumi up, even if I'm not alphabetizing or passing optional parameters Actual: The diff persists indefinitely

[ixti]

I believe this is related to: https://github.com/pulumi/pulumi-aws/issues/1985

[t0yv0]

If anyone is still affected by this, I'd appreciate a quick repro of a Pulumi program demonstrating the problem, it would really helps us narrow this down and look at some resolution options.

[t0yv0]

So apparently this issue pertains to containerDefinitions of ecs.TaskDefinition that is typed as string but represents a complex JSON structure. #1985 is likely correctly identified as a root cause - there is a lack of upstream normalization for the JSON for the purposes of diff. This is still open upstream. We may consider patching upstream to make this work sooner rather than later.

https://www.pulumi.com/registry/packages/aws/api-docs/ecs/taskdefinition/