GJS - D-Bbus 自動內觀(Introspect)與配置代理個體

/*************************************************************
rock.dbus
Copyright 2011 rock <shirock.tw@gmail.com>
License: GNU LGPL (http://www.gnu.org/licenses/lgpl.html)
*************************************************************/
const _Lang = imports.lang;
_Lang.copyProperties(imports.dbus, this);

/**
分析輸出端點的 XML 資料，轉成下列的表格形式:
  {
    name: 端點名稱,
    inSignature: 輸入參數的 DBus 型態簽名,
    outSignature: 輸出參數的 DBus 型態簽名
  };
@param export_node : DBus 輸出端點的 XML 資料。
 它可以是 DBus Method，也可以是 DBus Signal。
@return false | 參數內容表.
 */
function _parseDIXArgs(export_node) {
    var po = { name: false, inSignature: '', outSignature: '' };
    po.name = export_node.@name.toString();
    if (po.name == null || po.name.length == 0)
        return false;

    var n = 0, i = 0;
    /*
    n = export_node.arg.length();
    print("\t\tNumber of Arg: " + n);
    var arg_node;
    for (var i = 0; i < n; ++i) {
        arg_node = export_node.arg[i];
        // <arg name="interface" direction="in" type="s"/>
        print("\t\tArg name: "  + arg_node.@name +
              "; dir: "         + arg_node.@direction +
              "; type: "        + arg_node.@type)
    }
    */

    var ds = {inSignature: 'in', outSignature: 'out'};
    var d, args, sig;
    for (d in ds) {
        try {
            args = export_node.arg.(@direction == ds[d]);
        }
        catch(e) {
            if (e.name == "ReferenceError")
                args = export_node.arg;
            else
                throw e;
        }
        n = args.length();
        if (n > 0) {
            sig = []
            for (i = 0; i < n; ++i) {
                sig.push(args[i].@type);
            }
            po[d] = sig.join('');
        }
    }
    return po;
}

/**
分析 DBus Introspect XML 內容。
分析輸出端點的 XML 資料，轉成 gjs DBus.proxifyPrototype 要求的表格形式。
@param introspection Introspect 回傳的 XML 原始文件。
@return DBus介面原型表
 */
function _parseDBusIntrospectXML(introspection) {
    var x = new XML(introspection.replace(/<!DOCTYPE [^>]+>/,'')); // gjs supports E4X.


    // The DOCTYPE description of DBus XML look like illegal for E4X,


    // so I need to strip it.



    var export_types = {method: 'methods', signal: 'signals'};
    var extype, extypeval;
    var number_export = 0, export_node;
    var iface_table = {};
    var iface_node, iface_desc, result;

    for(var i = 0; i < x.interface.length(); ++i) {
        iface_node = x.interface[i];
        iface_desc = {
            name: iface_node.@name.toString(),
            methods: [],
            signals: []
        };

        for (extype in export_types) {
            extypeval = export_types[extype];
            number_export = iface_node[extype].length();
            if (number_export > 0) {
                iface_desc[extypeval] = [];
                for(var j = 0; j < number_export; ++j) {
                    export_node = iface_node[extype][j];
                    result = _parseDIXArgs(export_node);
                    if (result)
                        iface_desc[extypeval].push(result);
                }
            }
        } //foreach export_types


        iface_table[iface_desc.name] = iface_desc;
    } // foreach interface


    return iface_table;
}

/**
內觀 DBus 服務的原型資訊。
@return prototypes 內觀所得的原型資訊表(prototypes)。
 如果指定的 DBus 服務沒有實作 Introspectable 介面，則 prototypes 為 false。
 */
function IntrospectPrototype(bus, service_name, object_path, callback) {
    var introspectableProxy = new IntrospectableProxy(bus,
            service_name, object_path);

    var prototypes = false;
    var mainloop = imports.mainloop;

    introspectableProxy.IntrospectRemote(function(result){
        if (result != null && result.length > 0)
            prototypes = _parseDBusIntrospectXML(result);
        if (callback == undefined)
            mainloop.quit("");
        else
            callback(prototypes);
    },
    CALL_FLAG_START);

    if (callback == undefined)
        mainloop.run("");
    return prototypes;
}

/**
DBus 遠端個體代理者工廠.
args:
 required:
    bus
    service_name
    object_path
    interface_name

 option:
    interface_prototype
    callback
 */
function ProxyObjectFactory(args)
{
    var poc = false;    // proxy object class


    var po = false;     // proxy object


    var proto = false;  // prototype



    function _construct_proxy_object(proto) {
        poc = new Function("this._init();");
        poc.prototype = {
            _init: function() {
	            args.bus.proxifyObject(this, args.service_name, args.object_path);
            }
        };
        // 將介面原型注入代理類別


        proxifyPrototype(poc.prototype, proto);
        po = new poc();
        poc = false; // release


    }

    if (args.interface_prototype) {
        proto = args.interface_prototype;
    }
    else if (args.callback) {
        IntrospectPrototype(args.bus, args.service_name, args.object_path,
            function(protos){
                if (protos[args.interface_name] == null)
                    return false;
                proto = protos[args.interface_name];
                _construct_proxy_object(proto);
                return args.callback(po);
            });
        return true;
    }
    else {
        var protos = IntrospectPrototype(args.bus, args.service_name, args.object_path);
        if (protos[args.interface_name] == null)
            return false;
        proto = protos[args.interface_name];
        protos = false; //release


    }
    _construct_proxy_object(proto);

    if (args.callback)
        return args.callback(po);
    return po;
}

//const DBus = imports.dbus;


const DBus = imports.rock.dbus;
const Mainloop = imports.mainloop;

// new way via rock.dbus.


// Case 1: 在程式狀態進入 mainloop 之前可用此形式。


let notifier = DBus.ProxyObjectFactory({
    bus: DBus.session,
    service_name:   'org.freedesktop.Notifications',
    object_path:    '/org/freedesktop/Notifications',
    interface_name: 'org.freedesktop.Notifications'});

const NetworkManagerServiceName = 'org.freedesktop.NetworkManager';

let network_manager = DBus.ProxyObjectFactory({
    bus:        DBus.system,
    service_name:       NetworkManagerServiceName,
    object_path:        '/org/freedesktop/NetworkManager',
    interface_name:     'org.freedesktop.NetworkManager'});

network_manager.GetDevicesRemote(function(paths){
    // 此間內容已處於 mainloop 狀態，必須使用下列兩種形式調用 DBus.ProxyObjectFactory.


    for (let i in paths) {
        print("Path: " + paths[i]);

        // Case 2: 若不知介面原型，則必須給予回呼函數.


        // async (callback) mode:


        DBus.ProxyObjectFactory({
            bus:    DBus.system,
            service_name:   NetworkManagerServiceName,
            object_path:    paths[i],
            interface_name: 'org.freedesktop.DBus.Properties' ,
            callback: function(network_device){
                network_device.GetAllRemote("org.freedesktop.NetworkManager.Device",
                function(result){
                    print("-- begin callback output (should display after sync output) --");
                    for (var p in result)
                        print("\t" + p + ": " + result[p]);
                    print("-- end callback output --");
                });
            }
        });

        // Case 3: 你給予介面原型(interface_prototype), 則流程可循序進行.


        // sync mode:


        let network_device = DBus.ProxyObjectFactory({
            bus:    DBus.system,
            service_name:   NetworkManagerServiceName,
            object_path:    paths[i],
            interface_name: 'org.freedesktop.DBus.Properties',
            interface_prototype: DBus.Properties});

        network_device.GetAllRemote("org.freedesktop.NetworkManager.Device", function(result){
            print("-- begin sync output --");
            for (var p in result)
                print("\t" + p + ": " + result[p]);
            print("-- end sync output --");
        });
   }
});

notifier.NotifyRemote(
    "appname", 0, "message-im", "Test", "end after 2 seconds", [], {}, -1,
    function(result) {
        print("result: " + result);
    },
    DBus.CALL_FLAG_START
);

var source_id = Mainloop.timeout_add_seconds(2, function(){
    print("quit");
    Mainloop.quit('');
    return false;
});

Mainloop.run('');