Decentralized Instant Messaging (JavaScript SDK)

Dependencies

• Latest Versions

Name	Version	Description
Cryptography		Crypto Keys
Ming Ke Ming (名可名)		Decentralized User Identity Authentication
Dao Ke Dao (道可道)		Universal Message Module
DIMP (去中心化通讯协议)		Decentralized Instant Messaging Protocol

Extensions

Content

extends CustomizedContent

ContentProcessor

/**
 *  Customized Content Processing Unit
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *  Handle content for application customized
 */
app.cpu.AppCustomizedProcessor = function (facebook, messenger) {
    CustomizedContentProcessor.call(this, facebook, messenger);
    this.__handlers = {};  // String => CustomizedContentHandler
};
var AppCustomizedProcessor = app.cpu.AppCustomizedProcessor;

Class(AppCustomizedProcessor, CustomizedContentProcessor, null);

AppCustomizedProcessor.prototype.setHandler = function (app, mod, handler) {
    this.__handlers[app + ':' + mod] = handler;
};

// protected
AppCustomizedProcessor.prototype.getHandler = function (app, mod) {
    return this.__handlers[app + ':' + mod];
};

// Override
AppCustomizedProcessor.prototype.filter = function (app, mod, content, rMsg) {
    var handler = this.getHandler(app, mod);
    if (handler) {
        return handler;
    }
    // default handler
    return CustomizedContentProcessor.prototype.filter.call(this, app, mod, content, rMsg);
};

/*  Command Transform:

    +===============================+===============================+
    |      Customized Content       |      Group Query Command      |
    +-------------------------------+-------------------------------+
    |   "type" : i2s(0xCC)          |   "type" : i2s(0x88)          |
    |   "sn"   : 123                |   "sn"   : 123                |
    |   "time" : 123.456            |   "time" : 123.456            |
    |   "app"  : "chat.dim.group"   |                               |
    |   "mod"  : "history"          |                               |
    |   "act"  : "query"            |                               |
    |                               |   "command"   : "query"       |
    |   "group"     : "{GROUP_ID}"  |   "group"     : "{GROUP_ID}"  |
    |   "last_time" : 0             |   "last_time" : 0             |
    +===============================+===============================+
 */
app.cpu.GroupHistoryHandler = function (facebook, messenger) {
    BaseCustomizedHandler.call(this, facebook, messenger);
};
var GroupHistoryHandler = app.cpu.GroupHistoryHandler;

Class(GroupHistoryHandler, BaseCustomizedHandler, null);

// Override
GroupHistoryHandler.prototype.handleAction = function (act, sender, content, rMsg) {
    if (content.getGroup() === null) {
        var text = 'Group command error.';
        return this.respondReceipt(text, rMsg.getEnvelope(), content, null);
    } else if (GroupHistory.ACT_QUERY === act) {
        return transformQueryCommand.call(this, content, rMsg);
    }
    return BaseCustomizedHandler.prototype.handleAction.call(this, act, sender, content, rMsg);
};

var transformQueryCommand = function (content, rMsg) {
    var transceiver = this.getMessenger();
    if (!transceiver) {
        return [];
    }
    var info = content.copyMap(false);
    info['type'] = ContentType.COMMAND;
    info['command'] = GroupCommand.QUERY;
    var query = Content.parse(info);
    if (Interface.conforms(query, QueryCommand)) {
        return transceiver.processContent(query, rMsg);
    }
    var text = 'Query command error.';
    return this.respondReceipt(text, rMsg.getEnvelope(), content, null);
};

ContentProcessorCreator

app.cpu.ClientContentProcessorCreator = function (facebook, messenger) {
    BaseContentProcessorCreator.call(this, facebook, messenger);
};
var ClientContentProcessorCreator = app.cpu.ClientContentProcessorCreator;

Class(ClientContentProcessorCreator, BaseContentProcessorCreator, null);

Implementation(ClientContentProcessorCreator, {

    // protected
    createCustomizedContentProcessor: function (facebook, messenger) {
        var cpu = new AppCustomizedProcessor(facebook, messenger);

        // 'chat.dim.group:history'
        cpu.setHandler(
            GroupHistory.APP,
            GroupHistory.MOD,
            new GroupHistoryHandler(facebook, messenger)
        );

        return cpu;
    },

    // Override
    createContentProcessor: function (type) {
        var facebook = this.getFacebook();
        var messenger = this.getMessenger();
        switch (type) {

            // application customized
            case ContentType.APPLICATION:
            case 'application':
            case ContentType.CUSTOMIZED:
            case 'customized':
                return this.createCustomizedContentProcessor(facebook, messenger);

            // ...
        }
        // others
        return BaseContentProcessorCreator.prototype.createContentProcessor.call(this, type);
    },

    // Override
    createCommandProcessor: function (type, cmd) {
        var facebook = this.getFacebook();
        var messenger = this.getMessenger();
        switch (cmd) {
        
            // handshake
            case Command.HANDSHAKE:
                return new HandshakeCommandProcessor(facebook, messenger);
                
            // ...
        }
        // others
        return BaseContentProcessorCreator.prototype.createCommandProcessor.call(this, type, cmd);
    }
});

Usage

To let your AppCustomizedProcessor start to work, you must override BaseContentProcessorCreator for message types:

1. ContentType.APPLICATION
2. ContentType.CUSTOMIZED

and then set your creator for GeneralContentProcessorFactory in the MessageProcessor.

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