why does this module fail to find the aws_instance

[ketzacoatl]

I feel like I might be overlooking a simple mistake, but I've been over this again and again and I am still getting confusing behavior.

Here is a simplifed version of the code I'm working with..

In one source file...

# salt master instance
resource "aws_instance" "master" {
    ...
}

..and in another file:

# defines an ASG with some other stuff for us
module "cluster-a" {
    ...
    user_data = <<END_USER_DATA
...
salt:
  minion:
    master: ${aws_instance.master.private_dns}
...
END_USER_DATA

This fails:

* Resource 'aws_instance.master' not found for variable 'aws_instance.master.private_dns'

If I drop the reference to the aws_instance.master resource, the error goes away and the salt master instance is first in the build plan. tf graph shows the instance near last, while the cluster is first. Is this spin off from #1178 or un-related?

While debugging, I found that I could put in a reference to another resource in the same file as the aws_instance.master resource, and the module was happy with that reference.

This made me curious.. could I add another instance with a reference to the aws_instance.master? I added:

resource "aws_instance" "foo" {
    key_name = "${aws_instance.master.private_dns}"
    ami = "${var.ami}"
    associate_public_ip_address = true
    instance_type = "t2.small"
    availability_zone = "${aws_subnet.mgmt-a.availability_zone}"
    security_groups = ["${aws_security_group.salt-master.id}"]
    subnet_id = "${aws_subnet.mgmt-a.id}"
} 

and tf plan is fine and happy with that reference, but not when provided to the module. I tested that with and without depends_on = "aws_instance.master".

I first ran into the error with 0.4.x, so I upgrade to 0.5.x, but the problem persists.

[mitchellh]

Well, at least the error existed with 0.4.x. I've tagged it so we can look at it.

[ketzacoatl]

In case I was not clear, the error pasted above is from 0.5.x. Either way, let me know if more information or testing it helpful!

[ketzacoatl]

This may be a duplicate of #1916, I will test to confirm. And the last comment above on versions was incorrrect (sorry!)

[mitchellh]

This is a dup of #1916 and its fixed

[ketzacoatl]

confirmed here too, sorry for the delayed reply!

[ghost]

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