Types
JSON supports very limited number of types: string, number, boolean, object, array, null. Specifying JSON type is often not enough when it comes HTTP API definition and to what is allowed/prohibited as query/header/body value. For example, if the endpoint expects date and time in ISO 8601 format then in JSON it's just a string, though API user supposed to pass a string only in a specific format.
The null is a problem across all JSON types. All fields can be null in JSON. Though usually API is very sensitive to null values and does not allow nulls everywhere.
Spec has it's own list of supported types to close gaps mentioned above and to provide declarative way of defining types. This section describes these types.
Primitive Types
int int32
number
-2147483648 to 2147483647
long int64
number
-9223372036854775808 to 9223372036854775807
float
number
32 bit IEEE 754 single-precision float
double
number
64 bit IEEE 754 double-precision float
decimal
number
arbitrary-precision signed decimal
bool boolean
boolean
string str
string
uuid
string
lower case hex symbols with hyphens as 8-4-4-4-12
date
string
ISO 8601 yyyy-mm-dd
datetime
string
ISO 8601 yyyy-mm-ddThh:mm:ss.ffffff
json
object
any unstructured JSON
empty
N/A
represents nothing, similar to unit is some langs
Nullable Types
By default all types can't have null value. The ? modifier after type defines nullable type. For example string can not be null though string? can have null value.
Array and Dictionary
Following modifiers allow to specify data structures:
the_type[]
array
array of items of the_type
the_type{}
object
dictionary with property values of the_type
For example string[] represents array of strings. The type int{} represents JSON object where all properties values are integers.
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