_expand query string //query string parameter feature of json-server 

    "products": [

        {

            "id": 1,

            "locationId": [1, 2, 3, 4, 5],

            "productTypeId": 1,

            "name": "Extra",

            "price": 700

        }]

---------------------------------------------------------

     "productTypes": [

        {

            "id": 1,

            "type": "Gum"

        }]

---------------------------------------------------------

http://

localhost:8088/products/?_expand=productTypeId&_expand=productType

​

        {

        "id": 1,

        "locationId": [1,2,3,4,5],

        "productTypeId": 1,

        "name": "Extra",

        "price": 700,

        "productType": {"id": 1,"type": "Gum"}

        }