Ground DB

GroundDB is a fast and thin layer providing Meteor offline database and methods - Taking cloud data to the ground.

##Creating a GroundDB object

  // Return a grounded Meteor.Collection
  var list = new GroundDB('list');

  or

  // Get the groundDB of existing Meteor.Collection
  var list = new Meteor.Collection('list');
  var groundList = new GroundDB(list);

  or

  // Ground an existing Meteor.Collection  
  var list = new Meteor.Collection('list');
  // just ground the database:
  GroundDB(list);

Example of different patterns. Grounding a Meteor.Collection will attach the cache, resume and cross tabs update offline

Live basic test

##Features:

• Ligth footprint
• Broad browser support Chrome, Safari, Firefox and Internet Explorer 9
• Fallback to normal Meteor.Collection if no localstorage
• Resume of changes in collections
• Resume of methods
• Works offline updating cross window tabs
• Support for SmartCollection

##Support Tested on Chrome, Safari, Firefox and IE9 (though appcache is not supported in IE9 tabs are updated when offline) - but all browsers that support localstorage contains a FF safe test of localstorage

If localstorage is not supported the groundDB simply work as a normal Meteor.Collection

##Meteor Collection Interface GroundDB is like a normal Meteor.Collection - but changes and outstanding methods are cached and resumed.

##Concept Localstorage is simple and widely supported - but slow - Thats why we only use it for caching databases and methods + trying to limit the read and writes from it.

GroundDB saves outstanding methods and minimongo db into localstorage - The number of saves is minimized. It's less than a save pr. change

When the app loads GroundDB resumes methods and database changes - made when offline and browser closed.

##Ground user details It's possible to mount an allready existing collection on a groundDB eg.:

  GroundDB(Meteor.users);

The example will keep Meteor.user() returning correct user details - even if offline - Supports smartCollections by this option too

##Security GroundDB works just like a normal Meteor.Collection why allow and deny still works.

##Resume of outstanding methods Database changes and methods will be sent to the server just like normal. The methods are sent to server after relogin - this way this.userId isset when running on the server. In other words: Just like normal

##Events The event api is as follows:

GroundDB.onQuotaExceeded = function() {};
GroundDB.onResumeDatabase = function(name) {};
GroundDB.onResumeMethods = function() {};
GroundDB.onMethodCall = function(methodCall) {};
GroundDB.onCacheDatabase = function(name) {};
GroundDB.onCacheMethods = function() {};
GroundDB.onTabSync = function(key) {};

##Future

• At the moment the conflict resolution is pretty basic last change recieved by server wins. This could be greatly improved by adding a proper conflict handler. For more details look at comment in server.js

##Contributions Feel free to send issues, pull requests all is wellcome

Kind regards Morten