Installation

indexeddb.Source is installed into your project's lib directory, much like any other Enyo plugin, for example layout or onyx. See this post in Enyo Wiki for details.

Generally, you want to add indexeddb.Source plugin as a git submodule of your project, placed under lib/indexeddb directory.

One way to do that is to run the following at your project's root directory:

git submodule add https://github.com/vtomilin/EnyoIndexedDBSource.git lib/indexeddb

Then you should add indexeddb.Source dependency to your top-level package.js file:

enyo.depends(
    '$lib/layout',
    '$lib/onyx',
    '$lib/indexeddb',
    // Other dependencies...
);

Usage

Create an instance of indexeddb.Source sometime during your Applicaiton startup and introduce it to enyo.store:

create: enyo.inherit(function(sup) {
    return function() {
        var idbSource;
        sup.apply(this, arguments);

        try {
            idbSource = new indexeddb.Source({
                dbName: 'users',
                dbVersion: 1,
                dbInitSchema: this.initSchema.bind(this)
            });

            enyo.store.addSources({
                'idb': idbSource
            });
        } catch(error) {
            this.error('Failed to initialize IDB:', error);
        }
    };
})

A global signal event, onIDBOpened will be fired when database is initialized and ready for use, or if its initialization failed, in which case the event will have error property set to a particular error. If database has been successfully opened, then the event will contain a 'db' property, which holds the IDBDatabase object.

onIDBReady: function(sender, event) {
    if (event.error) {
        this.error('Failed to initialize IndexedDB:', event.error);
        return true;
    }

    this.$.users.fetch({
        source: 'idb',
        success: function(rec, opts, res) {
            this.log('Great success, starting...');
            this.start();
        }.bind(this),
        fail: function(rec, opts, error) {
            this.error(error);
        }.bind(this)
    });


    return true;
}

In the above example this.$.users is enyo.Collection object, configured in the sample application:

components: [
    {
        kind: 'enyo.Signals', onIDBOpened: 'onIDBReady'
    },
    {
        name: 'users',
        kind: 'enyo.Collection',
        model: 'db.IDBUser',
        url: 'user'
    }
]

Further, you simply use data management methods(fetch, commit, destroy), provided by Enyo's data framework(enyo.Collection, enyo.Model).

Whereas commit and destroy generally do not require additional options, fetch frequently does. These are options, which control its behavior:

• opts.params.index is an optional index name to use in the object store. If not specified, a default key(primary) will be used.
• opts.params.key is an optional key or key range. If the key is a simple value then it is used directly to locate records, which match it. The key range is defined by an object, which should define appropriate properties:
  • lower key's lower bound value. If not defined, then the key range is unbound from the lower end.
  • upper key's upper bound value. If not defined, then the key range is unbound from the upper end. NOTE at least one, lower or upper property must be given.
  • lowerOpen optional boolean indicating whether records, which match lower key should be excluded from the result set.
  • upperOpen optional boolean indicating whether records, which match upper key should be excluded from the result set.
• opts.params.singleItem optional boolean(defaults to false), specifying whether a single record is requested. This could be useful for efficiency reasons, when pulling out an object by its primary key. If this option is given, other options are ignored except key and index.
• opts.params.direction optional direction string of dataset traversal, which will determine the order, which records will be returned at. Possible values are:
  • next this is the default
  • prev the dataset will be traversed in reverse
  • nextunique
  • prevunique
• opts.params.offset optional offset in result set to return values from.
• opts.params.limit optional number of records to return.

NOTE that rec.url(which is your Collection or Model url property) will be used to infer underlying object store to operate on.

Also see samples directory for examples.

© Vitaly Tomilin

Licensed under LGPL v3