JSON-RPC报文结构

JsonRpc.kt

import com.fasterxml.jackson.annotation.JsonInclude

open class Request<P>(
    /**
     * A String specifying the version of the JSON-RPC protocol.
     * MUST be exactly "2.0".
     */
    val jsonrpc: String = Version20,

    /**
     * A String containing the name of the method to be invoked.
     * Method names that begin with the word rpc followed by a period character (U+002E or ASCII 46) are reserved
     * for rpc-internal methods and extensions and MUST NOT be used for anything else.
     */
    val method: String,

    /**
     * A Structured value that holds the parameter values to be used during the invocation of the method.
     * This member MAY be omitted.
     */
    @get:JsonInclude(JsonInclude.Include.NON_NULL)
    val params: P?,

    /**
     * An identifier established by the Client that MUST contain a String, Number, or NULL value if included.
     * If it is not included it is assumed to be a notification.
     * The value SHOULD normally not be Null and Numbers SHOULD NOT contain fractional parts
     */
    @get:JsonInclude(JsonInclude.Include.NON_NULL)
    val id: Int? = null,
) {
    companion object {
        const val Version20 = "2.0"
    }
}

open class Response<R, D>(
    /**
     * A String specifying the version of the JSON-RPC protocol. MUST be exactly "2.0".
     */
    val jsonrpc: String = Request.Version20,

    /**
     * This member is REQUIRED on success.
     *
     * This member MUST NOT exist if there was an error invoking the method.
     *
     * The value of this member is determined by the method invoked on the Server.
     */
    @get:JsonInclude(JsonInclude.Include.NON_NULL)
    val result: R? = null,

    /**
     * This member is REQUIRED on error.
     *
     * This member MUST NOT exist if there was no error triggered during invocation.
     *
     * The value for this member MUST be an Object as defined in section 5.1.
     */
    @get:JsonInclude(JsonInclude.Include.NON_NULL)
    val error: Error<D>? = null,

    /**
     * This member is REQUIRED.
     *
     * It MUST be the same as the value of the id member in the Request Object.
     *
     * If there was an error in detecting the id in the Request object (e.g. Parse error/Invalid Request), it MUST be Null.
     */
    @get:JsonInclude(JsonInclude.Include.NON_NULL)
    val id: Int? = null,
) {
    companion object {
        fun <R> result(id: Int?, result: R): Response<R, Void> {
            return Response(
                jsonrpc = Request.Version20,
                result = result,
                error = null,
                id = id
            )
        }

        fun <D> error(id: Int?, code: Int, message: String = "", data: D? = null): Response<Void, D> {
            return Response(
                jsonrpc = Request.Version20,
                result = null,
                error = Error(code, message, data),
                id = id
            )
        }
    }
}

class Error<D>(
    /**
     * A Number that indicates the error type that occurred.
     *
     * This MUST be an integer.
     */
    val code: Int,

    /**
     * A String providing a short description of the error.
     *
     * The message SHOULD be limited to a concise single sentence.
     */
    var message: String = "",

    /**
     * A Primitive or Structured value that contains additional information about the error.
     * This may be omitted.
     * The value of this member is defined by the Server (e.g. detailed error information, nested errors etc.).
     */
    @get:JsonInclude(JsonInclude.Include.NON_NULL)
    val data: D? = null,
) {
    init {
        if (message == "") {
            message = when(code) {
                0 -> "成功"
                ParseError -> "解析错误"
                InvalidRequest -> "非法请求"
                MethodNotFound -> "方法不存在"
                InvalidParams -> "非法参数"
                InternalError -> "内部错误"
                else -> "未知错误"
            }
        }
    }

    companion object {
        const val ParseError = -32700
        const val InvalidRequest = -32600
        const val MethodNotFound = -32601
        const val InvalidParams = -32602
        const val InternalError = -32603
        // -32000 to -32099 ServerError
    }
}