feat: Added workaround for variable type any (terraform-aws-modules#79)

Author: antonbabenko

README.md

@@ -69,6 +69,22 @@ module "s3_bucket" {
 }
 ```
 
+## Terragrunt and `variable "..." { type = any }`
+
+There is a bug [#1211](https://github.com/gruntwork-io/terragrunt/issues/1211) in Terragrunt related to the way how the variables of type `any` are passed to Terraform.
+
+This module solves this issue by supporting `jsonencode()`-string in addition to the expected type (`list` or `map`).
+
+In `terragrunt.hcl` you can write:
+
+```terraform
+inputs = {
+  bucket    = "foobar"            # `bucket` has type `string`, no need to jsonencode() 
+  cors_rule = jsonencode([...])   # `cors_rule` has type `any`, so `jsonencode()` is required
+}
+```
+
+
 ## Examples:
 
 * [Complete](https://github.com/terraform-aws-modules/terraform-aws-s3-bucket/tree/master/examples/complete) - Complete S3 bucket with most of supported features enabled

main.tf

@@ -28,7 +28,7 @@ resource "aws_s3_bucket" "this" {
   }
 
   dynamic "cors_rule" {
-    for_each = var.cors_rule
+    for_each = try(jsondecode(var.cors_rule), var.cors_rule)
 
     content {
       allowed_methods = cors_rule.value.allowed_methods
@@ -58,7 +58,7 @@ resource "aws_s3_bucket" "this" {
   }
 
   dynamic "grant" {
-    for_each = var.grant
+    for_each = try(jsondecode(var.grant), var.grant)
 
     content {
       id          = lookup(grant.value, "id", null)
@@ -69,7 +69,7 @@ resource "aws_s3_bucket" "this" {
   }
 
   dynamic "lifecycle_rule" {
-    for_each = var.lifecycle_rule
+    for_each = try(jsondecode(var.lifecycle_rule), var.lifecycle_rule)
 
     content {
       id                                     = lookup(lifecycle_rule.value, "id", null)