Serialisation
A simple serialisation framework is also provided. Uses the visit_struct library to automatically serialise and deserialise visitable classes/structs.
BSON
A simple serialisation framework to serialise and deserialise visitable classes/structs to and from BSON.
The framework provides the following primary functions to handle (de)serialisation:
marshall<Model>( const Type& )- to marshall the specified object to a BSON document.unmarshall<Model>( bsoncxx::document::view view )- unmarshall the BSON document into a default constructed object.unmarshall<Model>( Model& m, bsoncxx::document::view view )- unmarshall the BSON document into the specified model instance.
The framework handles non-visitable members within a visitable root object. Custom implementations can be implemented.
For non-visitable classes/structs, implement the following functions as appropriate:
bsoncxx::types::bson_value::value bson( const <Class/Struct Type>& model )that will produce a BSON document as a value variant for the data encapsulated in the object.void set( <Class/Struct Type>& field, bsoncxx::types::bson_value::view value )that will populate the model instance from the BSON value variant.
For partially visitable classes/structs, implement the following
populatecallback functions as appropriate:void populate( const <Class/Struct Type>& model, bsoncxx::builder::stream::document& doc )to add the non-visitable fields to the BSON stream builder.void populate( <Class/Struct Type>& model, bsoncxx::document::view view )to populate the non-visitable fields in the object from the BSON document.
JSON
A simple serialisation framework to serialise and deserialise visitable classes/structs to and from JSON.
Similar to the BSON framework, the JSON framework also handles non-visitable members within a visitable root object. Custom implementations can be implemented.
For non-visitable classes/structs, implement the following functions as appropriate:
boost::json::value json( const <Class/Struct Type>& model )that will produce a JSON value for the data encapsulated in the object.void set( const char* name, <Class/Struct Type>& field, simdjson::ondemand::value& value )that will populate the model instance from the JSON value.
For partially visitable classes/structs, implement the following
populatecallback functions as appropriate:void populate( const <Class/Struct Type>& model, boost::json::object& object )to add non-visitable fields to the JSON object.void populate( const <Class/Struct Type>& model, simdjson::ondemand::object& object )to populate non-visitable fields from the JSON object.
Validation
JSON input mostly comes via HTTP from untrusted sources. Consequently, there is a need for validating the JSON input. Basic support for input validation is provided via a validate function.
A validate( const char*, M& ) function is defined. This is to for validating the JSON input being parsed. A default specialisation is provided for std::string fields. This rejects strings with more than 40% (configurable) special characters. Users are advised to implement specific implementations specific to their domain requirements. Users may also use environment variables to influence the default implementation.
JSON_PARSE_VALIDATION_IGNORE- Environment variable that expects a comma or space separated list of field names that should be ignored by the validator. Default values arepassword, version. Example:export SPT_JSON_PARSE_VALIDATION_IGNORE='password, file, version, firmware, identifier'SPT_JSON_PARSE_VALIDATION_RATIO- Environment variable (double) that sets the maximum allowed ratio of special characters in the input string. Default is0.4. Example:export SPT_JSON_PARSE_VALIDATION_RATIO='0.35'