Wsrtjtyk

I create the resource group and the vNet in the main.tf and I reference module in the same file. The problem is, module cannot access these resources from the module. related code (most of the code removed, only relevant parts left):

main.tf:

module "worker" {

  source = "./vmLoop"



  vmName = "worker"

  prefix = "${var.reference["name"]}"

  loop   = "${var.reference["workerCount"]}"

}



resource "azurerm_resource_group" "rg" {

  name     = "${var.reference["name"]}"

  location = "${var.reference["location"]}"

}

How do I reference this resource group in the module? inside main.tf I can do this: "${azurerm_resource_group.rg.name}". Not only that, if I want to use data inside the module, that would fail because the resource is not yet created (most of the code removed, only relevant parts left):

Module.tf:

data "azurerm_resource_group" "rg" {

  name = "${var.prefix}"

}

Everything works fine if I precreate resource groupvnet.

In arm template, I would add a dependsOn property. However, modules in terraform do not support depends_on.

There's a fairly hackish workaround to this.

You can use depends_on on output variables of upstream module in the downstream, BUT you must make sure you use the variable in the downstream module, not just use it in the depends_on clause.

Unfortunately, that's not an ideal solution and it might not be applicable in some situations.

In the module you should be passing the subnetID or resource group, or whatever you are creating as a variable. For instance in your main config you might call the following:

module "vnet" {

  source              = "Azure/network/azurerm"

  resource_group_name = "${var.resource_group}"

  vnet_name           = "${terraform.workspace}-vnet"

  location            = "${var.arm_region}"

  address_space       = "${var.arm_network_address_space}"

  subnet_prefixes     = ["${var.arm_subnet1_address_space}", "${var.arm_subnet2_address_space}"]

  subnet_names        = ["subnet1", "subnet2"]



  tags = {

    environment = "${terraform.workspace}"

  }

}

Then invoke your vmdeploy module that using the subnetID as follows:

module "vmdeploy" {

 source = "./vmdeploy"

 subnetID = "${module.vnet.vnet_subnets[0]}"

}

By referencing the other module as a value for the vmdeploy module you are creating an implicit dependency that Terraform will recognize and include in the resource graph.

Within the module itself you would define a variable called subnetID like this:

var "subnetID" {}

Does that help?

You need to pass the name of the Resource Group to the module.
i.e.:

module "worker" {

  source = "./vmLoop"



  rg     = "${azurerm_resource_group.rg.name}"    

  vmName = "worker"

  prefix = "${var.reference["name"]}"

  loop   = "${var.reference["workerCount"]}"

}

Then in the worker module code itself, you would use the rg var for the worker's Resource Group.