a trouble about the fetch function #142

qkhhimkfrgw · 2014-07-29T02:38:29Z

Hi! Thank you for reading my problem about Backbone.localStorage.

I'm sorry to tell that may be I had found a bug.

I'm not sure if it is a bug or not, but I have a problem like this:

// create one record without specifing an id and the id is generated by the localStorage.guid() function
var collection = new ModelCollection();
collection.createTestData();
collection.fetch({async: false});
collection.at(0).destroy();
// create one record again
collection.createTestData();
collection.fetch({async: false});
if (collection.size() > 0) {
    collection.at(0).destroy();
} else {
    alert('data not found');
}

The step is that:

createTestData() // create one random record
fetch() // the record is getted
destroy() // the key point!
createTestData() // create one random record agian
fetch() // fetch again, but data not found

As you see, the record won't be found in the second time if I delete records before and do not specify an id and the id is generated by the localStorage.guid() function.

How can I solve the problem? Do I have to specify one id?

jeromegn · 2014-08-04T14:01:56Z

What's that {async: true} in the collection fetch method?

Can you add tests to this project to show me how this is failing?

qkhhimkfrgw · 2014-08-05T01:06:59Z

Here is the full source of one test.

<body>
    <script src="js/vendor/jquery-1.11.0.min.js"></script>
    <script src="js/vendor/underscore.js"></script>
    <script src="js/vendor/backbone.js"></script>
    <script src="js/vendor/backbone.localStorage.js"></script>
    <script>
        var TestModel = Backbone.Model.extend({
            defaults: {
                field: ''
            },
            localStorage: new Backbone.LocalStorage('tests-backbone')
        });
        var TestCollection = Backbone.Collection.extend({
            model: TestModel,
            localStorage: new Backbone.LocalStorage('tests-backbone')
        });
        window.localStorage.clear();
        var collection = new TestCollection();
        collection.create({field: '1'});
        collection.fetch();
        if (collection.size() > 0) {
            collection.invoke('destroy');
            alert('data found');
        }
        else {
            alert('data not found');
        }
    </script>    
</body>

It shows me 'data not found' in the real chrome browser,
but 'data found' in the jsfiddle(http://jsfiddle.net/qkhhimkfrgw/c32uL/5/).
If I change the TestModel definition like this:

var TestModel = Backbone.Model.extend({
            defaults: {
                field: ''
            },
           var TestModel = Backbone.Model.extend({
            defaults: {
                field: ''
            }//,
           // localStorage: new Backbone.LocalStorage('tests-backbone')
        });
});

It runs without any problems.
Maybe the localStorage of TestModel is the problem,
but I can not comment out the localStorage of TestModel.
Sometimes I use new TestModel ({...}).save(), and sometimes I will use TestCollection.create(...).

scott-w · 2017-02-28T19:12:12Z

I'm inclined to think that this is correct behaviour - model.destroy() is supposed to synchronise with the server/localstorage so I'd expect fetch to return nothing.

scott-w closed this as completed Feb 28, 2017

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a trouble about the fetch function #142

a trouble about the fetch function #142

qkhhimkfrgw commented Jul 29, 2014

jeromegn commented Aug 4, 2014

qkhhimkfrgw commented Aug 5, 2014

scott-w commented Feb 28, 2017

a trouble about the fetch function #142

a trouble about the fetch function #142

Comments

qkhhimkfrgw commented Jul 29, 2014

jeromegn commented Aug 4, 2014

qkhhimkfrgw commented Aug 5, 2014

scott-w commented Feb 28, 2017