wwa::json_rpc Namespace Reference

Library namespace. More...

Namespaces
namespace	details
	Contains the implementation details of the JSON RPC library.

Classes
class	dispatcher
	A class that manages JSON RPC method handlers and processes JSON RPC requests. More...
class	dispatcher_private
	Private implementation of the JSON RPC dispatcher class. More...
class	exception
	JSON RPC Exception class. More...
struct	hasher
	Custom hasher for std::string_view. More...
struct	jsonrpc_request
	Represents a JSON RPC request. More...

Functions
static void	from_json (const nlohmann::json &j, jsonrpc_request &r)
	Deserializes a JSON object into a jsonrpc_request structure.

Variables
static constexpr std::string_view	err_bad_id_type = "ID must be either a number, a string, or null"
	Error message for when the ID is not a number, a string, or null.
static constexpr std::string_view	err_bad_params_type = "Parameters must be either an array or an object or omitted"
	Error message for when the parameters are not an array or an object.
static constexpr std::string_view	err_empty_batch = "Empty batch request"
	Error message for when the batch request is empty.
static constexpr std::string_view	err_empty_method = "Method cannot be empty"
	Error message for when the method is empty.
static constexpr std::string_view	err_invalid_params_passed_to_method = "Invalid parameters passed to method"
	Error message for when the parameters passed to the method are not correct.
static constexpr std::string_view	err_method_not_found = "Method not found"
	Error message for when the method is not found.
static constexpr std::string_view	err_not_jsonrpc_2_0_request = "Not a JSON-RPC 2.0 request"
	Error message for when the request is not a JSON-RPC 2.0 request.

Detailed Description

Library namespace.

Function Documentation

from_json()

static void wwa::json_rpc::from_json ( const nlohmann::json & j, jsonrpc_request & r )

static

Deserializes a JSON object into a jsonrpc_request structure.

Parameters

j	The JSON object to deserialize.
r	The jsonrpc_request structure to populate.

This function deserializes a JSON object into a jsonrpc_request structure.

• It extracts the jsonrpc version, method name, params, and id from the JSON object.
• If the params field is not present, it defaults to an empty array.
• If the params field is an object, it is wrapped in an array.

Note

This function cannot be moved to an anonymous namespace because of Argument-Dependent Lookup (ADL).

See also

https://www.jsonrpc.org/specification#request_object

https://github.com/nlohmann/json?tab=readme-ov-file#arbitrary-types-conversions

Definition at line 56 of file dispatcher_p.cpp.

{
    r.params = nlohmann::json(nlohmann::json::value_t::discarded);
    r.id     = nlohmann::json(nlohmann::json::value_t::discarded);
 
    j.at("jsonrpc").get_to(r.jsonrpc);
    j.at("method").get_to(r.method);
 
    if (j.contains("params")) {
        j.at("params").get_to(r.params);
    }
 
    if (j.contains("id")) {
        j.at("id").get_to(r.id);
    }
 
    if (r.params.is_discarded()) {
        r.params = nlohmann::json::array();
    }
    else if (r.params.is_object()) {
        r.params = nlohmann::json::array({r.params});
    }
}