Terraform Filter Map and Get List

The terraform file demonstrates how to filter a map of key-value pair and get the map index of the keys which satisfy a given criteria. The main terraform resource used is: null_data_source

Requirements

The code was tested with:

1. terraform version 0.11.7

Demonstration

1. Given a terraform input file:

   listener_action={
       "HTTPS:43" = "HTTP:80"
       "HTTP:80"   = "HTTP:80"
       "HTTPS:443" = "HTTP:80"
       "HTTPS:543" = "HTTP:80"
   }
   

2. run the terraform logic situated in file using command:

   terraform init
   terraform apply --var-file terraform.tvars
   

3. the output should be:

   Outputs:
   
    index_key_https = [
     1,
     2,
     3
    ]
   
    input_map = {
     HTTP:80 = HTTP:80
     HTTPS:43 = HTTP:80
     HTTPS:443 = HTTP:80
     HTTPS:543 = HTTP:80
    }
   

   where the input_map value is how terraform ordered the input map provided in step (1) and the index_key_https is a list of key index which has HTTPS in the key, i.e. 1, 2 and 3.