aws_instances data source

[hashibot]

This issue was originally opened by @mattlqx as hashicorp/terraform#12376. It was migrated here as part of the provider split. The original body of the issue is below.

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I would find it useful to have an aws_instances data source that would be able to execute a filter and return the instance IDs of multiple instances. Presently the aws_instance data source says:

NOTE: If more or less than a single match is returned by the search, Terraform will fail. Ensure that your search is specific enough to return a single Instance ID only.

My use-case is that have a Terraform repo that has some common shared infrastructure (like HTTP hosts that hand-out 301s for whatever URL they're given) and I want to attach that to multiple AWS ALBs that are in separate Terraform repos (per application). I would like to do a search on those instances based on tags and be able to use the result list in an aws_alb_target_group_attachment. I'd really like to be able to have an aws_alb_target_group data source, but this is an acceptable (and useful in more ways) alternative.

Right now, the only real way I can get those instances is to hardcode the instance IDs in individual aws_instance data sources. I can work out some outputs where the hosts are created, and work them into being imported into the application Terraforms but this additional layer increases complexity and can become stale or out-of-sync if not done correctly. It's better just to hardcode the IDs for now.

[magnusthorne]

I need to be able to query AWS for IP addresses by tag. "show me all my jump servers"

[mattlqx]

Thanks so much! Great work!

[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!