Terraform issue creating the resource "azurerm_synapse_linked_service" specifically with the "type_properties_json" field

I am trying to create a Synapse Workspace Linked Service using Terraform and am running into a constant snag with the "type_properties_json" field that is (required).

When I try to establish a Linked Service to an SFTP resource type, I can do so through the portal no problem, however trying to do so with Terraform is constantly providing me with errors. I am using the JSON code format referenced here, but the "type_properties_json" field keeps erroring out as I believe it is expecting a "String" and I am instead providing a Map[string] type.

The error I keep receiving during the terraform apply is json: cannot unmarshal string into Go value of type map[string]interface {}

My specific code looks like the following:

resource "azurerm_synapse_linked_service" "linked-service" {
synapse_workspace_id = azurerm_synapse_workspace.synapse.id

name                 = "name"
type                 = "Sftp"
type_properties_json =  <<JSON
    {
        "host": "x.x.com",
        "port": 22,
        "skipHostKeyValidation": false,
        "hostKeyFingerprint": "ssh-rsa 2048 xx:00:00:00:xx:00:x0:0x:0x:0x:0x:00:00:x0:x0:00",
        "authenticationType": "Basic",
        "userName": "whatever_name,
        "password": "randompassw"
    }
    JSON
depends_on = [azurerm_synapse_firewall_rule.allow]

}

Running out of hope here and am now looking to crowd source to see if anyone else has ever ran into this problem!!

This is because of the password parameter you are passing. As per this Microsoft documentation, it should be passed as below:

        "password": {
            "type": "SecureString",
            "value": "<value>"
        }

Instead of

"password": <value>

I tested the same in my environment using your code where I faced the exact same issue:

So, I used the below code, applying the solution mentioned above:

resource "azurerm_synapse_linked_service" "example" {
  name                 = "SftpLinkedService"
  synapse_workspace_id = azurerm_synapse_workspace.example.id
  type                 = "Sftp"
  type_properties_json = <<TYPE
       {
            "host": "xxx.xx.x.x",
            "port": 22,
            "skipHostKeyValidation": false,
            "hostKeyFingerprint": "<SSH-publicKey>",
            "authenticationType": "Basic",
            "userName": "adminuser",
            "password": {
                "type": "SecureString",
                "value": "<Value>"
            }
        }
TYPE
  depends_on = [
    azurerm_synapse_firewall_rule.example,
    azurerm_synapse_firewall_rule.example1
  ]
}

Output: