app.js

var net = require('net');
var Events = require("events").EventEmitter;

var TIME_OUT = 60 * 1000 * 10;

/**
 * @param setting
 * @constructor
 */
function OpenApiClient(options, callback) {
    options || (options = {});
    callback || (callback = function() {});

    var self = this;

    if (!options.appkey) {
        throw "appkey is required ";
    }

    this._events = new Events();

    self._client = net.connect({
        port: options.port || 9500,
        host: options.host || "127.0.0.1"
    }, function(err) {
        if (err) {
            callback(err);
        }
        self._client.write(JSON.stringify({
            type: "auth",
            appkey: options.appkey || ""
        }));
    });

    this._timeoutId = setInterval(function() {
        if (!self._closeflag) {

            if (new Date - self._timeout > TIME_OUT) {
                self._events.emit("timeout");
                self.close();
                return;
            }

            self._client.write(JSON.stringify({
                type: "keepalive"
            }))
        }
    }, 1000 * 60 * 5);

    this._timeout = new Date - 0;

    self._client.on("data", function(data) {
        var json = {},
            dataStr = "";
        try {
            dataStr = data.toString();
            json = JSON.parse(dataStr);
        } catch (e) {
            callback(e);
            return;
        }

        switch (json.type) {
            case "auth":
                if (json.err < 0) {
                    callback(json);
                } else {
                    callback();
                }

                break;

            case "keepalive":
                self._timeout = new Date - 0;
            default:
                self._events.emit("data", dataStr);
                break;
        }

    });

    self._client.on("close", function() {
        clearInterval(self._timeoutId);
        self._events.emit("close");
    });
}

OpenApiClient.prototype = {

    on: function() {
        this._events.addListener.apply(this._events, arguments);
    },

    off: function() {
        this._events.removeListener.apply(this._events, arguments);
    },

    close: function() {
        // destroy 异步触发close 时间， 存在可能 interval 先运行，造成 write 时候出错
        this._closeflag = true;
        this._client.destroy();
    }

}

module.exports = function(options, callback) {
    return new OpenApiClient(options, callback);
}