Module borsh::schema

Since Borsh is not a self-descriptive format we have a way to describe types serialized with Borsh so that we can deserialize serialized blobs without having Rust types available. Additionally, this can be used to serialize content provided in a different format, e.g. JSON object {"user": "alice", "message": "Message"} can be serialized by JS code into Borsh format such that it can be deserialized into struct UserMessage {user: String, message: String} on Rust side.

The important components are: BorshSchema trait, Definition and Declaration types, and BorshSchemaContainer struct.

• BorshSchema trait allows any type that implements it to be self-descriptive, i.e. generate it’s own schema;
• Declaration is used to describe the type identifier, e.g. HashMap<u64, String>;
• Definition is used to describe the structure of the type;
• BorshSchemaContainer is used to store all declarations and defintions that are needed to work with a single type.

Structs

• BorshSchemaContainer
  All schema information needed to deserialize a single type.

Enums

• Definition
  The type that we use to represent the definition of the Borsh type.
• Fields
  The collection representing the fields of a struct.

Traits

• BorshSchema
  The declaration and the definition of the type that can be used to (de)serialize Borsh without the Rust type that produced it.

Type Definitions

• Declaration
  The type that we use to represent the declaration of the Borsh type.
• FieldName
  The name of the field in the struct (can be used to convert JSON to Borsh using the schema).
• VariantName
  The type that we use for the name of the variant.