Design pattern for data lookups in JSON objects

So writing an application which uses a lot of user generated data. And in most cases I just use the mongodb id to look up whatever it is. So a typical example for this app is icons for categories. They are stored as a data set that gets passed around the application from the api that speaks to the mongodb to the api to a factory and then to the controller, and quite often I need to make a simple lookup. Lets say that the category looks as follows:

[
   {
       "_id":"55dc79efed0fcf4a58d4a68d",
       "categoryName":"Sport",
       "categoryDescription":"Sport and more sports",
       "categoryIcon":"55dc79b2ed0fcf4a58d4a68c",
       "__v":0
   }
]

categoryIcon is a reference to another table, at the time loaded in a factory, data looks as follows.

[
   {
       "_id":"55dc79b2ed0fcf4a58d4a68c",
       "iconName":"Sport",
       "cssString":"fa fa-futbol-o",
        "__v":0
    },
    {
       "_id":"55dc79b2ed0fcf4a58d4a69d",
       "iconName":"Travel",
       "cssString":
       "fa fa-plane",
       "__v":0
    }
]

So the way I have been resolving this is along the lines of

for (var i in icons){
    if( icons[i]._id == category.categoryIcon ){
        console.log("Found the Icon");
        category.cssString=icons[i].cssString;
    }
}

Easy, relatively fast, but seems a bit wasteful, so is there a smoother way. Made a simple jfiddle if anyone wants to test.

http://ift.tt/1PQYB7u