@parity/api/lib/transport/middleware.js

The Parity Promise-based API library for interfacing with Ethereum over RPC

"use strict";
// Copyright 2015-2019 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
var Middleware = /** @class */ (function () {
    function Middleware(transport) {
        this._transport = transport;
        this._subscribe = transport.subscribe;
        transport.subscribe = this.handleSubscribe.bind(this);
        this._handlers = {};
        this._subHandlers = {};
    }
    Middleware.prototype.registerSubscribe = function (method, handler) {
        if (method in this._subHandlers) {
            throw new Error(method + " is already defined in the middleware!");
        }
        this._subHandlers[method] = handler;
    };
    Middleware.prototype.register = function (method, handler) {
        if (method in this._handlers) {
            throw new Error(method + " is already defined in the middleware!");
        }
        this._handlers[method] = handler;
    };
    Middleware.prototype.handleSubscribe = function (api, callback, event) {
        // Don't ask
        var method = api.subscribe ? api.subscribe : event[0];
        var params = event.length === 2 ? event[1] : event;
        var handler = this._subHandlers[method];
        if (handler) {
            return handler(params, callback);
        }
        this._subscribe.call(this._transport, api, callback, event);
    };
    Middleware.prototype.handle = function (method, params) {
        var handler = this._handlers[method];
        if (handler) {
            return handler(params);
        }
        return null;
    };
    Middleware.prototype.rpcRequest = function (method, params) {
        return this._transport._execute(method, params);
    };
    return Middleware;
}());
module.exports = Middleware;