Decentralized Instant Messaging (Dart SDK)

Dependencies

• Latest Versions

Name	Version	Description
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

1. extends Content

extends CustomizedContent

2. extends ContentProcessor

import 'package:dimsdk/dimsdk.dart';


///  Handler for Customized Content
///  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
abstract interface class CustomizedContentHandler {

  ///  Do your job
  ///
  /// @param act     - action
  /// @param sender  - user ID
  /// @param content - customized content
  /// @param rMsg    - network message
  /// @return responses
  Future<List<Content>> handleAction(String act, ID sender, CustomizedContent content,
      ReliableMessage rMsg);

}


///  Customized Content Processing Unit
///  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class CustomizedContentProcessor extends BaseContentProcessor implements CustomizedContentHandler {
  CustomizedContentProcessor(super.facebook, super.messenger);

  @override
  Future<List<Content>> processContent(Content content, ReliableMessage rMsg) async {
    assert(content is CustomizedContent, 'customized content error: $content');
    CustomizedContent customized = content as CustomizedContent;
    // 1. check app id
    String app = customized.application;
    List<Content>? res = filter(app, content, rMsg);
    if (res != null) {
      // app id not found
      return res;
    }
    // 2. get handler with module name
    String mod = customized.module;
    CustomizedContentHandler? handler = fetch(mod, customized, rMsg);
    if (handler == null) {
      // module not support
      return [];
    }
    // 3. do the job
    String act = customized.action;
    ID sender = rMsg.sender;
    return await handler.handleAction(act, sender, customized, rMsg);
  }

  // protected
  List<Content>? filter(String app, CustomizedContent content, ReliableMessage rMsg) {
    /// override for your application
    String text = 'Content not support.';
    return respondReceipt(text, content: content, envelope: rMsg.envelope, extra: {
      'template': 'Customized content (app: \${app}) not support yet!',
      'replacements': {
        'app': app,
      }
    });
  }

  // protected
  CustomizedContentHandler? fetch(String mod, CustomizedContent content, ReliableMessage rMsg) {
    /// override for your module
    // if the application has too many modules, I suggest you to
    // use different handler to do the jobs for each module.
    return this;
  }

  @override
  Future<List<Content>> handleAction(String act, ID sender, CustomizedContent content, ReliableMessage rMsg) async {
    /// override for customized actions
    String app = content.application;
    String mod = content.module;
    String text = 'Content not support.';
    return respondReceipt(text, content: content, envelope: rMsg.envelope, extra: {
      'template': 'Customized content (app: \${app}, mod: \${mod}, act: \${act}) not support yet!',
      'replacements': {
        'app': app,
        'mod': mod,
        'act': act,
      }
    });
  }

}

3. extends ExtensionLoader

import 'package:dimsdk/plugins.dart';


/// Extensions Loader
/// ~~~~~~~~~~~~~~~~~
class CommonLoader extends ExtensionLoader {

  // protected
  void registerCustomizedFactories() {
    
    // Application Customized
    Content.setFactory(ContentType.APPLICATION, ContentParser((dict) => AppCustomizedContent(dict)));
    Content.setFactory(ContentType.CUSTOMIZED, ContentParser((dict) => AppCustomizedContent(dict)));
    
  }

  @override
  void registerContentFactories() {
    super.registerContentFactories();
    
    registerCustomizedFactories();
  }

  @override
  void registerCommandFactories() {
    super.registerCommandFactories();

    // Handshake
    Command.setFactory(HandshakeCommand.HANDSHAKE, CommandParser((dict) => BaseHandshakeCommand(dict)));

  }

}

Usages

You must load all extensions before your business run:

import 'common_loader.dart';

void main() {

  var loader = CommonLoader();
  loader.run();
  
  // do your jobs after all extensions loaded.
  
}

Also, to let your CustomizedContentProcessor 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.

Copyright © 2023 Albert Moky