Filtered backbone.sync

backbone.sync.js

var handleUserLoggedOut = function(response, type, xhr) {
    var def = $.Deferred();
    if (resp.error === 'some error about ') {
        // Here we render a view for the user to log back in and track failed requests to re-apply them later
        return def.reject(resp.error);
    }
    return def.resolve(resp);
}

Backbone._sync = Backbone.sync;
Backbone.sync = function(method, model, options) {                                                      
    // CSRF token                                                                                     
    var formToken = config.formtoken;                                                                 
    if (method !== 'read' && formToken) {                                                             
        options.data = options.data || ({});                                                          
        _.defaults(options.data, {                                                                    
            csrf_token : formToken                                                                    
        });                                                                                           
    }                                                                                                 

    // Get reference to xhr object by first doing the sync method                                     
    var xhr = Backbone._sync(method, model, options);                                                 

    // Pipe through the logged out detector, this will return a $.Deferred, not the jquery xhr superset                                                                                                     
    var def = xhr.pipe(handleUserLoggedOut, handleServerErrors);                                      
    
    // Merge the xhr object back into the Deferred and return it                                      
    return _.extend(def, xhr);
};