gistfile1.txt

---
  tower_credential_types:
    - name:  SSH_Credential 
      description: Custom SSH Credential
      inputs: 
        fields: 
        - secret: true
          type: string
          id: my_private_key
          label: "Private Key"
        required:
        - my_private_key
        injectors:
         extra_vars:
           secret_key: "{{\_tower.filename.my_key\_ }}"
         file:
           template.my_key: "{{\_my_private_key\_ }}"