meteor soul

Meteor框架

https://www.meteor.com/

 

 

 

Meteor is an ultra-simple environment for building modern web applications.

With Meteor you write apps:

• in modern JavaScript
• that send data over the wire, rather than HTML
• using your choice of popular open-source libraries

   名字是流星的意思，意味着助理開發者，快速開發應用。

   同時還有數據更新很快的含義， 服務器端更新數據後，會很快的同步到全部觀測此數據的全部客戶端軟件上。

DDP

https://github.com/meteor/meteor/blob/devel/packages/ddp/DDP.md

DDP is a protocol between a client and a server that supports two operations:

• Remote procedure calls by the client to the server.
• The client subscribing to a set of documents, and the server keeping the client informed about the contents of those documents as they change over time.

      meteor應用框架靈魂是其定義的一套 DDP協議（Meteor's Distributed Data Protocol），

      此協議的實現兩個功能：

      1） 客戶端能夠調用服務器端的方法， 即支持遠程調用， 一些後端的邏輯， 就能夠寫在前端， 打薄後端。

      2）客戶端能夠訂閱服務器端的數據，當服務器端管理的數據改變後，全部訂閱此數據的客戶端都會被通知。

 

數據變動以下圖， 客戶端發起請求，改變服務端數據， 數據改變後，通知客戶端更新數據。

 

     minimongo負責客戶端數據的跟蹤，正常狀況會同服務器端的數據一致。

 

 

 NPM PACKAGE

ddp

https://www.npmjs.com/package/ddp

A callback style DDP (Meteor's Distributed Data Protocol) node client, originally based alansikora's node-js_ddp-client and Meteor's python client. Uses a more callback style approach.

 

客戶端RPC 和 訂閱。

 
  setTimeout(function () {
    /*
     * Call a Meteor Method
     */
    ddpclient.call(
      'deletePosts',             // name of Meteor Method being called
      ['foo', 'bar'],            // parameters to send to Meteor Method
      function (err, result) {   // callback which returns the method call results
        console.log('called function, result: ' + result);
      },
      function () {              // callback which fires when server has finished
        console.log('updated');  // sending any updated documents as a result of
        console.log(ddpclient.collections.posts);  // calling this method
      }
    );
  }, 3000);



  /*
   * Subscribe to a Meteor Collection
   */
  ddpclient.subscribe(
    'posts',                  // name of Meteor Publish function to subscribe to
    [],                       // any parameters used by the Publish function
    function () {             // callback when the subscription is complete
      console.log('posts complete:');
      console.log(ddpclient.collections.posts);
    }
  );
 
  /*
   * Observe a collection.
   */
  var observer = ddpclient.observe("posts");
  observer.added = function(id) {
    console.log("[ADDED] to " + observer.name + ":  " + id);
  };
  observer.changed = function(id, oldFields, clearedFields, newFields) {
    console.log("[CHANGED] in " + observer.name + ":  " + id);
    console.log("[CHANGED] old field values: ", oldFields);
    console.log("[CHANGED] cleared fields: ", clearedFields);
    console.log("[CHANGED] new fields: ", newFields);
  };
  observer.removed = function(id, oldValue) {
    console.log("[REMOVED] in " + observer.name + ":  " + id);
    console.log("[REMOVED] previous value: ", oldValue);
  };
  setTimeout(function() { observer.stop() }, 6000);
});
 

 

minimongo

https://www.npmjs.com/package/minimongo

    本地存儲， mongo風格API

A client-side MongoDB implementation which supports basic queries, including some geospatial ones.

Uses code from Meteor.js minimongo package, reworked to support more geospatial queries and made npm+browserify friendly. It was forked in January 2014.

It is either IndexedDb backed (IndexedDb), WebSQL backed (WebSQLDb), Local storage backed (LocalStorageDb) or in memory only (MemoryDb).

 

 
// Require minimongo
var minimongo = require("minimongo");
 
var LocalDb = minimongo.MemoryDb;
 
// Create local db (in memory database with no backing)
db = new LocalDb();
 
// Add a collection to the database
db.addCollection("animals");
 
doc = { species: "dog", name: "Bingo" };
 
// Always use upsert for both inserts and modifies
db.animals.upsert(doc, function() {
    // Success:
 
    // Query dog (with no query options beyond a selector)
    db.animals.findOne({ species:"dog" }, {}, function(res) {
        console.log("Dog's name is: " + res.name);
    });
});