Using "computed" values in maps not possible

[Alars-ALIT]

Terraform Version

Terraform v0.7.0-rc2

Affected Resource(s)

Terraform core

Terraform Configuration Files

resource "null_resource" "intermediates" {
    triggers = {
        test = "testing..."
    }
}


module "test_mod" {
  source = "./mod"

  services = {
    "name"             = "user-service"
    "min"              = "1"
    "max"              = "1"
    "desired"          = "1"
    "instance_type"    = "t2.small"
    "elb"              = "${null_resource.intermediates.triggers.test}" 
  }
}

variable "services"                { type = "list" }

resource "aws_autoscaling_group" "asg-test" {
  count                     = "${length(var.services)}"
  availability_zones        = ["test"]
  min_size                  = "${lookup(var.services[count.index], "min")}"
  max_size                  = "${lookup(var.services[count.index], "max")}"
  desired_capacity          = "${lookup(var.services[count.index], "desired")}"
  launch_configuration      = "any"
  vpc_zone_identifier       = ["any"]
  load_balancers            = ["${lookup(var.services[count.index], "elb")}"]  
}

Expected Behavior

Expected the map to contain a entry for "elb". I seems like "computed" values can't be passed in maps

Actual Behavior

Errors:

• lookup: lookup failed to find 'elb' in:

${lookup(var.services[count.index], "elb")}

Steps to Reproduce

terraform plan

[jen20]

Hi @Alars-ALIT! I can reproduce this - thanks for the concise example. I'll investigate what is going on here, as I see no reason in principle that this should not work.

[jen20]

Note to self for investigative context - in interpolationFuncLookup:

2016/06/24 14:49:03 [INFO] args: ([]interface {}) (len=2 cap=2) {
 (map[string]ast.Variable) (len=5) {
  (string) (len=3) "min": (ast.Variable) {Variable (TypeString): 1},
  (string) (len=3) "max": (ast.Variable) {Variable (TypeString): 1},
  (string) (len=7) "desired": (ast.Variable) {Variable (TypeString): 1},
  (string) (len=13) "instance_type": (ast.Variable) {Variable (TypeString): t2.small},
  (string) (len=4) "name": (ast.Variable) {Variable (TypeString): user-service}
 },
 (string) (len=3) "elb"
}

[jen20]

The issue here is that this value is not being passed through as a computed key.

[onlyanegg]

I'm seeing the same issue on 0.6.16. Is this related?

[jen20]

@coutotyler Can you show a configuration for 0.6.16? I suspect this was always broken and people are discovering it now that maps are a more prominent feature. I have a fix in the works for the 0.7 at the moment.

[onlyanegg]

yup, here you go: https://gist.github.com/coutotyler/42c6d82cc6f202adf21255fbeb16c041

[ocsi01]

Is it possible at all ( in v0.7rc-2) to define a list of maps? ( If I understand it well, the 'services' variable is a list, where each element of the list is a map.)
The question is also open for nested maps.

[jen20]

@ocsi01 Yes - the services variable in this example is a list of maps, where each element is a map. Nested maps are supported internally but are not exposed via HCL syntax at the moment.

[ocsi01]

@jen20 Does it mean at the moment ( v0.7rc-2) it's not possible to define multiple element in the 'services' list?
For example:

vpc_info          = [{      
"name"= "vpc1"
"cidr"= "10.3.0.0/16"
},{      
"name"= "vpc2"
"cidr"= "10.2.0.0/16"
}
]

I'm getting syntax error:

unexpected token while parsing list: LBRACE

As a workaround, I've found this syntax:

  vpc_info          = {      
          "name"= "vpc1"
          "cidr"= "10.3.0.0/16"
          }
  vpc_info          = {      
          "name"= "vpc1"
          "cidr"= "10.2.0.0/16"
          }

It is working well if I'm adding it as direct input to a module. However if I'm trying to pass it to an other module, I'm getting an error:

module "vpc" {
  source = "./vpc"
  vpc_info = "${var.vpc_info}"
}

cannot convert vpc_info2 value [map["cidr":"{Variable (TypeString): 10.3.0.0/16}" "name":"{Variable (TypeString): vpc1}"] map["name":"{Variable (TypeString): vpc2
}" "cidr":"{Variable (TypeString): 10.2.0.0/16}"]] to an ast.Variable for interpolation: value for conversion must be a string, interface{} or map[string]interface: got
ast.Variable

Any ideas?

[ghost]

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