JSON objects returns undefined

Question

I'm returning a JSON object using a 3rd party API. When I print out the variable I get the following:

category: 
{
    "sys":
    {
        "id":"44uyBvGjFmsmoU6uqiiSOq",
        "revision":1,
        "type":"Entry",
        "locale":"en-US",
        "contentType":
        {
            "sys":
            {
                "id":"2V5tBa4wf6cuMSIu4McuUc",
                "type":"Link",
                "linkType":"ContentType"
            }
        },
        "createdAt":"2014-09-13T22:40:39.901Z",
        "updatedAt":"2014-09-13T22:40:39.901Z",
        "space":
        {
            "sys":
            {
                "id":"t667fybp3v46",
                "type":"Link",
                "linkType":"Space"
            }
        }
    },
    "fields":
    {
        "name":"birth control"
    }
}

But when I try and access the variables using the following, I keep on getting "Possibly unhandled TypeError: Cannot read property 'name' of undefined" :

if (o.fields.category)
{
    var str = JSON.stringify(o.fields.category, undefined, 2);
    console.log(str);

    var json_category = JSON.parse(str);
    // console.log("--------------Category for the resource: " + o.fields.category);
    $.each(json_category, function(index, object){
        alert(10);
        var category = {};
        // console.log("--------------Category for the resource: " + object.sys);
        category.id = object.sys.id;
        // console.log("--------------Category for the resource: " + object.fields.name);
        category.name = object.fields.name;
        // console.log("--------------Category for the resource: " + object.sys.updatedAt);
        category.updatedAt = object.sys.updatedAt;
        categories.push(category);
    });
 }

Any help is greatly appreciated.

What does your call to this API look like? The problem is very likely to be that your API is asynchronous and you're not properly waiting for the result. — Pointy, Sep 14 '14 at 12:50
I'm using Contentful and their Javascript library https://www.contentful.com/developers/documentation/content-delivery-api/ — zee, Sep 14 '14 at 12:55
Well it's hard to say; it would be much more useful to debug from *inside* your callback to the `$.each()` loop. You don't have to stringify the object to log it; use `console.dir(object);` and you'll be able to inspect the object in the developer console. — Pointy, Sep 14 '14 at 13:01
I think I see what you mean. Do you think you can provide a bit of code. Sorry not the strongest with JSON. — zee, Sep 14 '14 at 13:01
Just replace that `alert(10)` call with `console.log("index: " + index + " object: ", object);` and have the browser developer console open. (The "Console" tab; the developer console has a lot of stuff in it nowadays.) — Pointy, Sep 14 '14 at 13:04
You can not access id directly use 'category.sys.id' instead of 'category.id', do the same for name. — Aria, Sep 14 '14 at 13:37

score 0 · Accepted Answer · answered Sep 15 '14 at 10:47

Changed my code to the following. Thanks to Pointy for providing the assistance, much appreciated.

if (o.fields.category)
{
    console.log(o.fields.category.fields.name);

    var category = {};
    category.id = o.fields.category.sys.id;
    category.name = o.fields.category.fields.name;
    category.updatedAt = o.fields.category.sys.updatedAt;
    categories.push(category);
}

record.categories = categories;
record.searchTags = search_tags;
records.push(record);

JSON objects returns undefined

1 Answers1

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