Proposal for an official JSON Schema for semver

[jenkin]

Semver has an official regex for validation.

We can use it to offer an official JSON Schema to validate a semver compliant string.

{
    "$schema": "http://json-schema.org/draft-07/schema#",
    "$id": "https://semver.org/semver.schema.json",
    "type": "string",
    "pattern": "^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-((?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\\.(?:0|[1-9]\\d*|\\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\\+([0-9a-zA-Z-]+(?:\\.[0-9a-zA-Z-]+)*))?$",
    "minLength": 5,
    "maxLength": 256,
    "description": "A semver.org compliant version number."
}

So in a custom schema you can refer to the official one using $ref attribute without copy-pasting anything.

{
    "type": "object",
    "properties": {
        "version": {
            "$ref": "https://semver.org/semver.schema.json"
        }
    }
}

See also this issue in json-schema-spec repository: json-schema-org/json-schema-spec#1108.

[michaelmior]

@jenkin Given that semver officially has no size limit, I would suggest removing maxLength. minLength also feels unnecessary since any valid version will be at least that long anyway.