list_of_maps.tf

variable "apigw_map" {
  description = "Map for APIGW Resources and Methods"
  default = {
    categories = {
      GET = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "categories"
      }
      PUT = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "categories"
      }
      POST = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "categories"
      }
      DELETE = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "categories"
      }
    }
    images = {
      GET = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "images"
      }
      PUT = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "images"
      }
      POST = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "images"
      }
      DELETE = {
        authorization = "NONE"
        authorizer_id = ""
        key_req       = true
        target_path   = "images"
      }
    }
  }
}


locals {
  intermediate = flatten([for key, dict in var.apigw_map:
  [ for method, value in dict:
  merge({"method"=method,"key"=key},value)
  ]])

  pseudo_dict = {for value in local.intermediate:
  md5(jsonencode(value)) => value
}


}


output "Name" {
   value = local.pseudo_dict
}

resource "null_resource" "example1" {
  for_each = local.pseudo_dict
  provisioner "local-exec" {
    command = "echo key: ${each.value.key} method: ${each.value.method} target_path: ${each.value.target_path}"
  }
}

output.txt

Apply complete! Resources: 0 added, 0 changed, 0 destroyed.

Outputs:

Name = {
  "2db86378ea26681fc77563bb5d4f4dc4" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "categories"
    "key_req" = true
    "method" = "PUT"
    "target_path" = "categories"
  }
  "7ee94572751da18716e4a93115b081c0" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "images"
    "key_req" = true
    "method" = "GET"
    "target_path" = "images"
  }
  "9ce4a84d870991794a675e6113641dcc" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "images"
    "key_req" = true
    "method" = "DELETE"
    "target_path" = "images"
  }
  "b46ccd6bae4c4e3c68e430abf62d8e95" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "categories"
    "key_req" = true
    "method" = "DELETE"
    "target_path" = "categories"
  }
  "bbb3fc87571a1b24e4e50fc79a3d72c4" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "categories"
    "key_req" = true
    "method" = "POST"
    "target_path" = "categories"
  }
  "dcf833fdfcd47001e3add967eba65606" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "images"
    "key_req" = true
    "method" = "PUT"
    "target_path" = "images"
  }
  "f0528cb0f26c46cd4e65ee5bfe6af09c" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "images"
    "key_req" = true
    "method" = "POST"
    "target_path" = "images"
  }
  "f46e1bed332223b42f1bfb3d143013d8" = {
    "authorization" = "NONE"
    "authorizer_id" = ""
    "key" = "categories"
    "key_req" = true
    "method" = "GET"
    "target_path" = "categories"
  }
}