gistfile1.js

.factory('Helper', function()
{
	return (function()
	{
		this.validateJson = function(jsonObject)
		{
			try
			{
				JSON.stringify(jsonObject);
				return true;
			}
			catch(ex)
			{
				return false;
			}
		};
	});
})
.filter('jsonKey', function(Helper)
{
	return function(jsonObject)
	{
		var helper = new Helper();
			
		if ( ! helper.validateJson(jsonObject) )
		{
			return false;
		}
			
		var result;
			
		angular.forEach(jsonObject, function(value, key)
		{
			if ( typeof result === 'undefined' )
			{
				result = key;
			}
		});
			
		return result;
	};
})
.filter('jsonValue', function(Helper)
{
	return function(jsonObject)
	{
		var helper = new Helper();
			
		if ( ! helper.validateJson(jsonObject) )
		{
			return false;
		}
			
		var result;
			
		angular.forEach(jsonObject, function(value, key)
		{
			if ( typeof result === 'undefined' )
			{
				result = value;
			}
		});
			
		return result;
	};
});