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Logging cyclic references

• A working demo is in project JSNLogDemo_Log4Net_Decycle

Some objects have cyclic references. That is, they refer to themselves. For example:

var a = { x: 1 };
a.self = a;

The problem is that the JSON.stringify method used to serialize objects into strings cannot handle this. Instead, it throws an exception, such as:

Uncaught TypeError: Converting circular structure to JSON

The solution is to use the JL.serialize option to set a custom method that does handle cyclic references:

1. Find yourself a library that deals with cyclic references. Personally I like cycle.js.
2. Write a method that takes an object, serializes it, and returns the resulting string. Such as this:

   <script src="cycle.js"></script>
   
   var decyclingSerializer = function(obj) {
       // JSON.decycle is defined in cycle.js
       var decycledObject = JSON.decycle(obj);
   
       return JSON.stringify(decycledObject);
   }

3. Tell JSNLog to use your new method:

   JL.setOptions({
       "serialize": decyclingSerializer
   });