Parse JSON serialised by CircularJSON

Question

I have a JSON object in my node.js code which contains circular references. To send this data to the browser, I used the NPM module circular-json to stringify the object and serialise the circular references:

var CircularJSON = require("circular-json");
app.get("/api/entries", function(req, res){ 
  contentClient.entries({"content_type": "xxxxxxxxxxx"}, function(err, entries){
    if (err) throw err;
    res.send(CircularJSON.stringify(entries));
  });
});

This works fine and sends serialised data through res.send(); Now, in my frontend Angular code I need to make the circular references usable. One of the serialised fields in the object looks like this on the client side: "~0~fields~twitter~1"

I tried the following in the browser:

1. Copied a version of circular-json.js to my frontend site
2. Linked to the script in my index.html like so: <script src="/framework/lib/circular-json.js"></script>
3. Set the CircularJson variable like so: var CircularJSON = window.CircularJSON;

4. Parse the incoming JSON like so:

   $http.get("/api/entries").then(function(res){ console.log(CircularJSON.parse(res.data[0])); });

I get the following error: SyntaxError: Unexpected token o

Answer 1

For one time call I think you can use $http as follows

function appendTransform(defaults, transform) {

  // We can't guarantee that the default transformation is an array
  defaults = angular.isArray(defaults) ? defaults : [defaults];

  // Append the new transformation to the defaults
  defaults.unshift(transform);
  return defaults;
}

$http({
  url: '...',
  method: 'GET',
  transformResponse: appendTransform($http.defaults.transformResponse,                function(value) {
    return CircularJSON.parse(value);
  })
});

Or for every call you can define an interceptors, examples are here: https://docs.angularjs.org/api/ng/service/$http

UPDATE: Unshift does not return the array. Modified the code, now it should work.