idiscovery

node中间件，支持服务自动发现，服务间通信，自动推选master服务，master服务crash后自动重新推选可用的服务作为master服务，支持added，removed，elected等事件监听。

Requirements

1. requirements

   democracy >= 1.3.0 
   ip >= 1.1.5
   redis >= 2.8.0  
   

Usage

1. install

   npm install idiscovery --save
   

2. initialize

   var Discovery = require("idiscovery");
   new Discovery({
       name: 'idiscovery' // Your current service name
       interval: 1000, // The interval (ms) at which `hello` heartbeats are sent to the other peers.
       timeout: 3000, // How long a peer must go without sending a `hello` to be considered down.
       weight: Math.random() * Date.now() // The highest weight is used to determine the new leader. Must be unique for each node.
       id: 'uuid' // (optional) This is generated automatically with uuid, but can optionally be set. Must be unique for each node.
       redis: {} // Your redis config for connecting to a redis server.
   });
   
   

3. Methods

   1. Returns the object containing all active nodes and their properties (including the one the method is called from).

   nodes()
   

   2. Returns the current leader node from the cluster.

   leader()
   

   3. Returns whether or not the current server is the leader.

   isLeader()
   

   4. If called on the current leader node, will force it to resign as the leader. A new election will be held, which means the same node could be re-elected.

   resign()
   

   5. Sends a custom event to all other nodes.

   send(customEvent, extraData)
   

4. Events All events return the data/configuration of the affected node as their first parameter.

   1. Fired when a new peer has been found.

   added
   

   2. Fired when a peer has gone down and subsequently been removed from the list.

   removed
   

   3. Fired when a new leader is selected.

   leader
   

   4. Fired on the server that has become the new leader.

   elected
   

   5. Fired on the server that has resigned as the leader.

   resigned
   

   6. Fired on all the server except the one that "sent" the event.

   custom/all other events
   

Installation with npm

• To install via Npm, simply do the following:

  执行install命令

      $ npm install idiscovery --save
  
  

  or

      $ vi package.json
  

  编辑package.json文件，添加如下配置:

      dependencies: {
          "idiscovery": "^0.0.1"
      }
  

  执行install命令

      $ npm install
  
  

Examples

The below example is easy to run on your local machine (also found in the test directory).

var Discovery = require('idiscovery');

var vote = new Discovery({
    name: "xxx",
    redis: {
        url: "redis://@127.0.0.1:6379/0",
        password: ""
    }
});

vote.on('added', function(data) {
  console.log('Added: ', data);
});

vote.on('removed', function(data) {
  console.log('Removed: ', data);
});

vote.on('elected', function(data) {
  console.log('You have been elected leader!');
});

vote.on('yyy', function(data) {
    console.log('yyy from %s', data.id, data.extra);
});

vote.send('yyy', {hello: 'world'});