communication

[niels1286]

Dear Naveen:

First of all, thank you for participating in the technical research business of the NULS community. We hope that more and more talents like you.

首先感谢您参与NULS社区的技术研究事业，我们希望像您这样的人才越来越多。

We have carefully read your module code and have some content to discuss with you.

我们认真的阅读了您的module代码，有一些内容想与您探讨

1, After reading your code, I find that your code is called an event module, but it is not a module, but an application.

1、读了你的代码后，发现你的代码虽然叫做event-module,但是其实并不是NULS模块，而是一个nuls的应用。

2, In the current architecture, the module still provides services in the way of java internal interface calls, that is, other modules can directly use EventService

2、目前的架构中，模块还是以java内接口调用的方式提供服务，就是其他模块可以直接使用EventService

3, For the use of spring, we are not against, but the bottom module does not consider the use of springs, to avoid restrictions

3、针对spring的使用，我们并不反对，但底层模块不考虑使用spring，避免受到限制

4、The underlying module has been considered in the event module, the responsibility is to perform asynchronous event processing between modules, similar to the publish subscription model.

4、底层模块的考虑中有过event-module，职责是进行模块间异步的事件处理，类似于发布订阅模型

5, Your approach is a good application production method, in the version after 1.1, provides a new protocol for carrying application data, you can do DAPP in this way.

5、你的这种做法，是很好的应用制作方式，在1.1之后的版本，提供了一个新的协议，用于承载应用数据，可以用你的这种方式做DApp。

6, we simply browsed your code. If there is something wrong, please correct me. The technical improvement needs to communicate with people like you.

6、我们只是简单的浏览了你的代码，如果有理解不对的地方请指正，技术的提高需要与您这样的人的沟通

[naveen7252]

Hi Niels,
Thanks for taking your time to review and provide the feedback.
For Point 1: Yes, this is a separate application(as we can run independently) but it can also be bootstrapped from Nuls.
But, as you said in points 2&4, it doesn't fulfill the requirement. I thought this module is for users/dapps/wallets to subscribe to these events,so I didn't think of inter-module interaction.

I have few questions, please help to clarify:

1. Is event module publisher for any event and other interested module can subscribe to those events?
2. Event module will have its own api to publish events which can be subscribed by third party like users/dapps/wallets etc ?
3. For point 2 in feedback, how would other module use EventService interface ? I mean in what cases.
4. can you please elaborate on point 5?

Can you provide the technical design for event module if the team have it already ?I am happy to work on the development of that.If not, I will come up with the design and let you know, lets discuss on it.

Thanks

[niels1286]

The team has started the design of the event module, but it is still in the perfect stage. The general content of the module has not been sorted out yet. The document is only available in Chinese. I will send you a try first, and then we will improve it together. Of course it is a better thing that you develop this module independently.
Document path:
document.md

[naveen7252]

Thanks for sharing the document, I will translate it to understand. Are we gonna use any broker for pub-sub implementation?

[niels1286]

You are welcome.For a while, we will put the design document on github, and you can submit the English version of the design document. In the current consideration, we do not plan to use heavyweight components such as Kafka, ActiveMQ, etc., but we are implementing our own code to implement a single-process publish-subscribe module.

[naveen7252]

Hi Niels, I have few questions on the design. Please help to clarify.
1.Are topics created while bootstrapping the event bus module and available for all other modules to publish/subscribe messages to these topics?
2. If question 1 answer is yes, moduleId(who actually creates topic) for addtopic command will always be event-bus module right?
3. Can other modules(except event-bus) create topics whenever they want to and publish messages to that topic?(it also depends on question 1 answer)
4. I believe event-bus module never publish/subscribe messages.

[lanjinsheng]

Hi Niels, I have few questions on the design. Please help to clarify.
1.Are topics created while bootstrapping the event bus module and available for all other modules to publish/subscribe messages to these topics?
2. If question 1 answer is yes, moduleId(who actually creates topic) for addtopic command will always be event-bus module right?
3. Can other modules(except event-bus) create topics whenever they want to and publish messages to that topic?(it also depends on question 1 answer)
4. I believe event-bus module never publish/subscribe messages.

===========================================================
设计文档这几天还会再更新，弱化主题概念，只有事件订阅与事件发布。事件发布时候，有订阅者，则消费，无订阅者，则不消费。

1、启动时候会加载订阅者的信息，主题可以认为是由发布者来创建。
2、内核模块和事件总线模块不会发布订阅消息
3、在发送消息的时候，就把事件主题带上。
4、每个模块的事件都会预先定义在开发者文档中

Design document will be updated over the next few days, weakening the topic, with only subscribe event and event publishing. When the event is released, subscribers will consume, no subscribers, and no consumption.

1. When module bootstrap, you will load the subscriber's information. The theme can be thought of by the publisher.

2, the kernel-module and event-bus module do not publish subscribe event.

3, when sending messages, bring the topic of the event.

4, each module event is pre defined in the developer document.

[naveen7252]

Thanks, I will wait for the updated document.

[naveen7252]

when do we expect updated design document ?
Can I get more details on below points please?

1. What should be done while bootstrapping event-bus module? I mean what information we load/start/create?
2. What should be done while bootstrapping other module(except kernel) with respect to events ? I mean what information we load/start/create during bootstrap?

I couldn't get full information from the document (Chinese doc) like images are not loaded and few translation issues.

[niels1286]

Hey, Naveen. I'm Emerson from NULS core team. We do want you to join us with development of event bus module of NULS.
Could you please download wechat and add me as firend, my wechat ID is emerson0421.Looking forward to your request.