A wrapper for storage engines which use the W3C Storage API
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README.md

jsonStorage

A light abstraction for DOMStorage (such as localStorage).

Installation

Ender.JS (Browser)

ender build json-storage

Node.JS (Server)

npm install localStorage json-storage

Usage

Made fo for Node.JS and Ender.JS (browser-side).

var localStorage = require('localStorage')
  , JsonStorage = require('json-storage')
  , db = JsonStorage(localStorage, 'my-app-prefix')
  , myValue = {
        foo: "bar"
      , baz: "quux"
    }
  ;

db.set('myKey', myValue); 
myValue = db.get('myKey');

API

  • JsonStorage(DOMStorage, 'application-prefix') // optional prefix
  • get(key)
  • set(key, value)
  • remove(key)
  • clear()
  • keys()
  • size()

null vs undefined in JSON

These notes do not reflect a bugs or defects in this library, they're simply to inform you of a few 'gotchas' inherent in JSON / DOMStorage conversion.

99.999% of the time these gotchas shouldn't effect you in any way. If they do, you're probably doing something wrong in the first place.

It is not valid to set undefined in JSON. So setting a key to undefined will remove it from the db.

This means that db.set('x') is the same as db.remove('x').

To save undefined, use null instead.

Note that both values that exist as null and values that don't exist at all will return null.

db.set('existing-key', null);
null === db.get('existing-key');
null === db.get('non-existant-key');

The special case of null as "null", aka "\"null\"":

null, and "null" both parse as null the "object", instead of one being the string (which would be "\"null\"").

Objects containing null, however, parse as expected { "foo": null, "bar": "null" } will parse as foo being null but bar being "null", much unlike the value "null" being parsed on its own.