Can't splat over a resource's list attribute

[thegedge]

The best example is for elasticache:

resource "aws_elasticache_cluster" "memcache" {
   …
}

output "cache_nodes" {
  value = "${join(",', aws_elasticache_cluster.memcache.cache_nodes.*.address)}"
}

When testing locally with our own stacks, cache_nodes isn't even an output when I do the above. For now we've simply restricted the cluster size to 1 and access the cache_node directly.

[maxrothman]

Any movement on being able to splat over list attributes?

[apparentlymart]

This will be supported in the next major version of Terraform, as described in the Generalized Splat Expressions article.

[apparentlymart]

In Terraform v0.12-alpha1 we can see the new "generalized splat" behavior working for all list values:

locals {
  example = [
    {
      id = "foo"
    },
    {
      id = "bar"
    },
    {
      id = "baz"
    },
  ]
}

output "example" {
  value = local.example.*.id
}

$ terraform output
example = [
  "foo",
  "bar",
  "baz",
]

Although the above uses a local value list for simplicity, the splat expression syntax can now be applied to any list value, regardless of where it is obtained from.

[ghost]

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