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Runtime generated objects serialization

If you think in a generic way about all well implemented RESTful APIs you will find a pattern that can be easily described and stored in metadata. Most RESTful API is just a combination of the following elements:

  • Resource location (URL)
  • HTTP method
  • Header information
  • Input parameters (required and optional)
  • Content type
  • Output parameters
  • Business logic description

Today I would like to discuss an interesting problem that I came across recently. Imagine for a second that you need to implement a RESTful API client which uses a combination of metadata which describes API and a user input in order to make a HTTP calls. 

In such a scenario you will quickly realize that for a subset of API calls you will need to develop a custom classes in order to have  them later serialized (to JSON or XML) in runtime so that you can send it via POST or PUT requests. This rises a question. Do I really need to implement N - 1 classes that represent all types that some API(s) expect(s) as a part of HTTP request body?

Well, maybe. In my case I decided to use a more generic approach and leverage a simplicity of standard data formats like JSON. The 'hack' is very simple. From a serialization point of view any class is just a container for properties of specific type - methods and interfaces we can skip as its have nothing to do with serialization. Lets than simplify a class generic description. A class is a collection or key-value pairs. Sounds similar isn't it? Maybe it sounds like JSON format description? This is correct...milestone achieved. 

We already know that we have a key-value pair type of collection. How to describe it from a data structure perspective? Very simple! Actually so simple that we have more than one option available.

We can use the followings:
  • Dictionary<string,object>
  • dynamic type
  • Anonymous types and var 
Other:
  • Approach with List<Tuple<string,object>> does not work! A result JSON has a structure with a property names like Item1, Item2....expected.
[{"Item1":"Name","Item2":"Damian"},{"Item1":"Surname","Item2":"Damian"},{"Item1":"Age","Item2":12},{"Item1":"Books","Item2":["Book 1","Book 2"]}]
  • If you know any other method (even crazy and geeky version) please let me know. Just don't send a one with reflection...
OK. It's time to serialize out classes.

1. By using Dictionary<string, object>

      // Dictionary approach
      Dictionary<string, Object> userDict = new Dictionary<string, object>();
      userDict.Add("Name", "Damian");
      userDict.Add("Surname", "Zapart");
      userDict.Add("Age", 12);
      userDict.Add("Books", new List<String> { "Book 1", "Book 2" });
 
      JsonConvert.SerializeObject(userDict);

2. By using a dynamic type

       // Dynamic type approach
       dynamic user = new
       {
           Name = "Damian",
           Surname = "Zapart",
           Age = 12,
           Books = new List<String> { "Book 1", "Book 2" },
       };
 
       JsonConvert.SerializeObject(user);









3. By using anonymous types




          // Anonymous approach
          var userAnonymous = new
          {
              Name = "Damian",
              Surname = "Zapart",
              Age = 12,
              Books = new List<String> { "Book 1", "Book 2" }
          };



And we done! Was a pleasure. Next time will focus on a performance of each solution.








Result JSON.

















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