Updating a document using the default ObjectId

Here are a few facts about keys and the way MongoDB deals with them.

• Documents in MongoDB require a key, _id, which uniquely identifies them.  
• This is a 12-byte binary value, read more from the source of truth, ObjectId.
• When inserting a new document, MongoDB will generate an ObjectId where one is not specified.
• There is a 'reasonable' chance that this will be unique at the time of creation.  
• All of the officially-supported MongoDB drivers use this type by default for _id values.

An annoyance I had with MongoDB, when I first started to use it, was the explicit update required on the default _id key/value pair.  To illusrate this here is a concrete example of what I mean.

I wanted to do this:
But I had to do this:
In this case, json is a JSON document passed from an HTML form via HTTP PUT, eventually ending up here at the DAO.  I was using the default _id implementation and thus would have expected save to do the figure that out and do the necessary work for me.

I just can't live those extraneous lines of code, it's too messy and too much to type every time.  I'll pull it out into a fromJson call, as I can see the pattern emerging and the odds of this reoccurring high.

I must have missed something in the API Docs as this cannot be an unusual requirement.  I would of at least expect to see it in a Util class...

Factory snippet:
Usage snippet:

I get to do what I wanted to now, but it still feels wrong.  It feels a little bit dirty.  It feels like a hack-o-la.  How can I do it better?

Convert HTML form to JSON and POST using jQuery

Reinventing the wheel is a pet hate of mine; I could list quite a few actually, but that's not the point of this post.  Sometimes it takes me so long to look for a wheel that I think has or should have already been invented that it would have been easier just to invent the wheel myself.

Recently I was playing around with jquery, pulling fields from a form and posting them as a JSON object to a set of services.  Nothing fancy, nothing difficult there.  However, when the data model started to mature beyond the most basic structure I soon realised I need an easy, repeatable way to pull structured/nested data from a a form and convert it into a JSON object prior to posting.

To create the following structure:


You will need to create the following references:


This is a complete working example that will parse the form, create the JSON obbject, POST it to a service and display the returned object in a table.



The form above will produce the following JSON.