Question

I’m using the following jQuery code to get a JSON file from CouchDB.

Function getURL() {
   var api_url = 'http://127.0.0.1:5984/couchcontentqueue/_design/DocCollections/_view/view_all_by_url_name?key="favorite-flickr-photos"&?callback=?';

   $.getJSON(api_url, function(json) {
      var type = json.type;
      var desc = json.description;
      $("#dropBox h3").html(type);
      $("#dropBox p").html(desc);
   });
};

When I do a GET on that URL it provides back the following:

{
    "total_rows":6,
    "offset":5,
    "rows":[
        {"id":"f5ba37e5af406ab079d596f7a1f30a2d","key":....}
    ]
}

Firebug gives me the following error:
invalid label
http://127.0.0.1:5984/couchcontentqueue/_design/DocCollections/_view/view_all_by_url_name?key=%22favorite-flickr-photos%22&?callback=jsonp1304111285023
Line 1

I can’t figure out how to get past that first line to get to the actual JSON object. Any ideas? Thanks.

Answer 1

?callback=

It looks like you are trying to do a JSONP request, but:

{“total_rows”:6, …

Is a plain JSON response and not a JSONP call. If you don’t mean to do a cross-domain JSONP request, get rid of the callback parameter and have jQuery parse the response as normal JSON.

If you do need to do cross-domain JSONP requests, and you understand the security risks of that, make sure you’re using an up-to-date CouchDB version and add the directive:

allow_jsonp = true

to the .ini file in the [http] section.

invalid label

is what you get when you try to execute/eval a string containing a JSON object. It is a quirk of JS parsing that the "x" in {"x": "foo"} is taken as a JavaScript ‘label’ (used rarely for continue statements) in a statement block, rather than an object property name in an object literal expression.

jQuery will use script execution instead of JSON parsing when it thinks you are doing a JSONP request. Having the ‘callback=’ parameter in your URL magically makes it think that.