Async Storage for Jetpack

This is a module for Mozilla's Addon-SDK that simplifies using IndexedDB in Firefox extensions, based on the localForage library.

Installation

The Add-on SDK supports loading modules from a node_modules directory via the jpm tool, so if you're using jpm all you need to do is this:

npm install --save jp-async-storage

If you're using cfx instead ( upgrade! upgrade! ) you can just to this:

cd <extension folder>/lib
wget https://raw.githubusercontent.com/canuckistani/jp-async-storage/master/lib/async-storage.js

Usage

let { AsyncStorage } = require("async-storage");

let config = {
  name: 'my-database',
  version: 1
};
AsyncStorage.open(config, function(e, r) {
  if (e) throw e;
  let item = {_id: 1, string: "Hello world"};
  AsyncStorage.setItem('key-'+item._id, item, function() {
    if (e) throw e;
    // if you got this far, you probably saved data!
  });
}):

Supported API

The localForage api is supported:

• setItem
• getItem
• removeItem
• getItems
• keys
• key
• length
• clear

There are two main differences:

1. Promises are not supported, only callbacks
2. callback arguments are node-style: the first argument is an error, and the second is hopefully your data.

Tests

First install jpm with npm install jpm -g, then run jpm test -b nightly -v with Firefox Nightly installed.

TODO

• look into using Promises
• consider using a Promise-based initialization method like localForage does with a bit more magic.