Reference

Default Type Mappings

Currently, the following types are mapped to JSON Schema.

Julia Type	JSON Schema Type
`Union{}`	`{"not": {}}`
`Tuple{}`	`{"type": "array", "maxItems": 0 }`
`Bool`	`{"type": "boolean"}`
Subtypes of `Integer` except `BigInt`	`{"type": "integer", "minimum": typemin(T), "maximum": typemax(T)}`
`BigInt`, `Integer`	`{"type": "integer"}`
Subtypes of `AbstractFloat`	`{"type": "number" }`
Subtypes of `Rational`	`{"type": "number" }`
Subtypes of `Irrational`	`{"type": "number" }`
Subtypes of `AbstractString`	`{"type": "string" }`
`Char`	`{"type": "string", "minLength": 1, "maxLength": 1 }`
`Symbol`	`{"type": "string" }`
`Date`	`{"type": "string", "format": "date" }`
`DateTime`	`{"type": "string", "format": "date-time" }`
`Time`	`{"type": "string", "format": "time" }`
`Regex`	`{"type": "string", "format": "regex" }`
`VersionNumber`	`{"type": "string", "pattern": "^\\d+\\.\\d+\\.\\d+.*$" }`
`Nothing`	`{"type": "null" }`
`Missing`	`{"type": "null" }`
`Any`	`{}`

Here, schema(T) denotes the schema generated for type T (which becomes a $ref).

Julia Type	JSON Schema Type
Subtypes of `AbstractArray`	`{"type": "array", "items": schema(eltype(T)) }`
Subtypes of `AbstractSet`	`{"type": "array", "items": schema(eltype(T)), "uniqueItems": true }`
`Tuple{T1, T2, …, TN}` (no Vararg)	`{"type": "array", "prefixItems": [schema(T1), …, schema(TN)], "minItems": N, "maxItems": N }`
`NTuple{N, T}`	`{"type": "array", "items": schema(T), "minItems": N, "maxItems": N }`
`Tuple{Vararg{T}}` or `Tuple{Vararg{T, N}}`	`{"type": "array", "items": schema(T) }`
`NamedTuple{(:a, :b, …), Tuple{TA, TB, …}}`	`{"type": "object", "properties": {"a": schema(TA), …}, "required": ["a", …], "additionalProperties": false }`
Subtypes of `AbstractDict{K, V}`	`{"type": "object", "additionalProperties": schema(V) }`

For more detailed examples, see the examples directory.

See the API Reference for detailed documentation of all exported functions.