TL;DR

Elastos.NET.Carrier.Nodejs.SDK is the Node.js Add-on for Elastos Carrier. It allows Javascript code to call Carrier C++ functions.

Design concerns

Thread safe

Carrier is multithreaded C++ module. JS is single thread. We need to make sure threads are well managed in NodeAddOn level. JS code call the addon to create new Carrier object. the addon will create new thread to handle the long running working thread(s) until it quits. JS caller can get a session ID to identify this particular carrier object. All communication between add-on and js code will have this session ID as the first arg.

Session management

When Carrier C++ code create a new Carrier object, it returns a memory pointer to the new gneerated carrier object. But the memory pointer cannot be sent to the js code. Instead, we will hold the object in add-on memory into a table. A unique session ID can find the pointer to this Carrier object. The session ID can be sent to JS. Everytime, when JS call any function, or any callback function will need this session ID to identify which Carrier object it is talking to.

Streaming

FAQ

Carrier.Nodejs.SDK vs Carrier.Trinity.SDK

What is Carrier.Trinity project?

Trinity project is a modified version of Chromium browser. It embedded the Elastos.Carrier into the browser, so that there is no need for a server. The decentralized webapp can be safely running inside the Trinity browser while connect to the P2P network using Carrier. Of course, other Elastos.RT services will be provided by the trinity as well.

Why do we need Carrier.Nodejs.SDK besides Carrier.Trinity?

Most of standard web/server application has a backend, very likely running on Node.js. Sometime the webapp need other services such as database which cannot be provided by Trinity at this moment. That's to say the backend is required. For these kind of webapp, we provide the Node.js addon which is called Carrier.Nodejs.SDK.

The addon can be used as a typical node.js modules using "import" or "require". It provide all the Carrier's functionalities to the js developers.

You can consider Carrier.Nodejs.SDK or Carrier.Trinity.SDK are just wrappers of Carrier C++ module. We try to keep both SDK using the same API so that you do not need to learn yet another sets of APIs.

Where to learn more about Carrier module?

This project is just a wrapper. For more detail of Carrier, please go to Elastos.NET.Carrier.Native.SDK

Are there any other SDK for other OS?

Yes, we are working on the SDK for Android, iOS, Mac, Windows, Linux, Nodejs and client-side-js. Please visit our code repo frequently to check latest updates.

Build from source

Ubuntu

Install Pre-Requirements

Execute following command to install all pre-requirements.

Build carrier native sdk Please goto https://github.com/elastos/Elastos.NET.Carrier.Native.SDK. Clone the code and build.

Install node

$ cd $(SRC_ROOT)
$ git clone --branch v9.10.0 https://github.com/nodejs/node.git
$ cd node
$ ./configure
$ make
$ make install

Check node version.

$ node --version
v9.10.0

Install node-gype

sudo npm install -g node-gyp

Build

Set the environment value about carrier native sdk header files and libraries path.

export CARRIER_NATIVE_SDK=$(SRC_CARRIER_NATIVE_SDK_ROOT)/build/_dist/Linux-x86_64/debug

if $(SRC_CARRIER_NATIVE_SDK_ROOT) is a relative path, please modify binding.gyp : "-L<!(echo $CARRIER_NATIVE_SDK)/lib" ==> "-L<(module_root_dir)/<!(echo $CARRIER_NATIVE_SDK)/lib"

From root directory run:

$ node-gyp configure
$ node-gyp build

Demo

$ cd ./example/demo
$ npm install
$ node ./example/demo/demo.js

See readme for more detail. This is a Medium blog post from community on how to build and run demo.js: https://medium.com/@radektomej/installing-and-running-of-elastos-node-js-demo-app-3f3aeba00e03

Sample app

Chat-App

code. This is a Nodejs desktop app (using nw.js). It can launch a js desktop UI. User can register and add friends, chat with friends. TODO: Add screen shot or demo video link here

Web Demo

client server This is a web UI demo based on original demo app. It use web UI instead of command line. It demos the same feature as the original demo.

More to come

Please create your own sample app and let us know. We will add your project links here and we will give you ELA reward.

Community Contribution

How to run the demo.js - Medium

Radek Tomsej (from Czech Republic) has this Medium post about how to build and run demo.js. Please go take a look at https://medium.com/@radektomej/installing-and-running-of-elastos-node-js-demo-app-3f3aeba00e03. Thank you Redek!

We want more!

We are looking for more active community members to contribute your idea, your experiences, your code, everything. Please raise an issue and assign to me(kevingzhang). Thanks

At this moment, we need the following material from the community

• Video and blog post about how to build and run Elastos Carrier
• A sample Web DApp running on top of Carrier, such as a web chat app for instance chatting for example. Jacky(liyangwood) from DaLian, China is working on one, we welcome more on this.
• Video and blog post to explain Carrier concept. (Kevingzhang will work on this)

https://medium.com/@radektomej/installing-and-running-of-elastos-node-js-demo-app-3f3aeba00e03