Tyk gateway json-04 schema validation for external json files

in docker cc gateway setup is this the right way to use the $ref ? i read in google and found multiple ways. but nothing is working
$ref : file:///phnumber.json
$ref: phnumber.json
$ref: https://mywebsite.com/phnumber.json

please help and this is very important for our work and this poc is completely failing. please throw any ideas.

this is like not working in docker with ubuntu or docker with windows.
req: { “name”: “id1”, “address” : { “line1” : “line1”}} → the address is sub-schema referred from external file. this one is configured as { “address”: “$ref”: “file:///ext1.json” } → not picking up and the schema validations are wrong.
i used all these three options
$ref : file:///phnumber.json
$ref: phnumber.json
$ref: https://mywebsite.com/phnumber.json
please help if any of you tried and working.