JSON
All JSON in the Versia protocol MUST be an I-JSON message, a restricted profile of JSON. Messages are signed as the exact bytes sent, so there is no canonical form to follow.
Encoding
All JSON data MUST be encoded in UTF-8. This is the only encoding supported by the Versia protocol. As I-JSON requires, keys and string values MUST NOT contain surrogate or noncharacter code points.
Line breaks inside string values MUST be Unix-style \n (LF), not Windows-style \r\n (CRLF). A receiver MUST treat an entity with a \r\n inside a string value as invalid. There is no rule on whitespace between JSON tokens.
Keys
Keys MUST NOT be empty. Senders MUST NOT send an object with duplicate keys.
Which keys an object can have depends on the object:
- Entity and structure fields use the names listed in this specification. Receivers ignore any others.
- Extension keys follow Extension Naming.
- Any other map documents its own keys where it is defined.
Values
Numbers
Numbers SHOULD NOT have greater magnitude or precision than an IEEE 754 double-precision number. Any form that JSON allows is valid, including 1.0 and 1e3.
Numeric fields state their type:
integer: a whole number from 0 to 2⁵³-1 (9007199254740991), in any form, so1000,1000.0and1e3are all valid. Other values MUST NOT be sent, and fail validation.float: an IEEE 754 double-precision number.
Optional Fields
Fields that are not marked as required are optional. Omitting a field and setting it to null mean the same thing. Senders SHOULD omit the field, and receivers MUST accept both.