phone.json

{
    "$schema": "http://json-schema.org/draft-04/schema#",
    "description": "Phone number. Must be represented in its canonical international format, as defined by the E.164 numbering plan.",
    "type": "object",
    "title": "Phone type",
    "properties": {
        "country_code": {
            "type": "string",
            "description": "Country calling code (CC) as defined by E.164. Combined length of CC+national must not be more than 15 digits. ",
            "minLength": 1,
            "maxLength": 3,
            "pattern": "^[0-9]{1,3}?$"
        },
        "national_number": {
            "type": "string",
            "description": "National number as defined by E.164. Combined length of CC+national must not be more than 15 digits. National number consists of National Destination Code (NDC) and Subscriber Number (SN).",
            "minLength": 1,
            "maxLength": 14,
            "pattern": "^[0-9]{1,14}?$"
        },
        "extension_number": {
            "type": "string",
            "description": "Extension number.",
            "minLength": 1,
            "maxLength": 15,
            "pattern": "^[0-9]{1,15}?$"
        }
    },
    "required" : ["country_code", "national_number"]
}