Synopse Open Source

We almost finished implementing a long-standing feature request, introducing MVC / MVVM for Web Applications (like RubyOnRails) in mORMot.
This is a huge step forward, opening new perspectives not only to our framework, but for the Delphi community.
In respect to the existing MVC frameworks for Delphi, our  solution is closer to Delphi On Rails (by the convention-over-configuration pattern) than the Delphi MVC Framework or XMM.
The mORMot point of view is unique, and quite powerful, since it is integrated with other parts of our framework, as its ORM/ODM or interface-based services.
Of course, this is a work in progress, so you are welcome to put your feedback, patches or new features!

We will now explain how to build a MVC/MVVM web application using mORMot, starting from the "30 - MVC Server" sample.
First of all, check the source in our GitHub repository: two .pas files, and a set of minimalist Mustache views.

This little web application publishes a simple BLOG, not fully finished yet (this is a Sample, remember!).
But you can still execute it in your desktop browser, or any mobile device (thanks to a simple Bootstrap-based responsive design), and see the articles list, view one article and its comments, view the author information, log in and out.

This sample is implemented as such:

For the sake of the simplicity, the sample will create some fake data in its own local SQlite3 database, the first time it is executed.

In a comment of a Google+ announcement about new C# features, Stephan did react about my naive enthusiasm about SmartPascal.

Apart from the fact that he did miss the numerous ways of creating Windows executable in this dialect (I quoted at least 5 diverse ways), he was chocked by the fact that the SmartPascal syntax, in its actual idiom, does not support generics.

But are generics mandatory?
I'm not speaking about any drug identified by its chemical name rather than its brand name (Wikipedia).
I would neither comment on the current Delphi implementation of generics (which may appear not so polished, nor very widely used, even in the Delphi RTL/FMX, but for TList<T> TDictionary<>).
Just share some thoughts about what is, to my opinion - which may be wrong and biased! - the most important part of today's programming.

It is pretty much possible that you would have to maintain and evolve a legacy project, based on an existing database, with a lot of already written SQL statements - see Legacy code and existing projects.

For instance, you would like to use mORMot for new features, and/or add mobile or HTML clients - see Cross-Platform clients.
In this case, the ORM advanced features - like ORM Cache or BATCH process, see BATCH sequences for adding/updating/deleting records - may conflict with the legacy code, for the tables which may have to be shared.
Here are some guidelines when working on such a project.

To be exhaustive about your question, we need to consider each ORM CRUD operation.
We may have to divide them in three kinds: read queries, insertions, and modifications of existing data.

You certainly noticed that WebSocket is the current trendy flavor for any modern web framework.
But does it scale? Would it replace HTTP/REST?
There is a feature request ticket about them for mORMot, so here are some thoughts - matter of debate, of course!
I started all this by answering a StackOverflow question, in which the actual answers were not accurate enough, to my opinion.

From my point of view, Websocket - as a protocol - is some kind of monster.

You start a HTTP stateless connection, then switch to WebSocket mode which releases the TCP/IP dual-direction layer, then you may switch later on back to HTTP...
It reminds me some kind of monstrosity, just like encapsulating everything over HTTP, using XML messages... Just to bypass the security barriers... Just breaking the OSI layered model...
It reminds me the fact that our mobile phone data providers do not use broadcasting for streaming audio and video, but regular Internet HTTP servers, so the mobile phone data bandwidth is just wasted when a sport event occurs: every single smart phone has its own connection to the server, and the same video is transmitted in parallel, saturating the single communication channel... Smart phones are not so smart, aren't they?

WebSocket sounds like a clever way to circumvent a limitation...
But why not use a dedicated layer?
I hope HTTP 2.0 would allow pushing information from the server, as part of the standard... and in one decade, we probably will see WebSocket as a deprecated technology.
You have been warned. Do not invest too much in WebSockets..

OK. Back to our existential questions...
First of all, does the WebSocket protocol scale?
Today, any modern single server is able to server millions of clients at once.
Its HTTP server software has just to be is Event-Driven (IOCP) oriented (we are not in the old Apache's one connection = one thread/process equation any more).
Even the HTTP server built in Windows (http.sys - which is used in mORMot) is IOCP oriented and very efficient (running in kernel mode).
From this point of view, there won't be a lot of difference at scaling between WebSocket and a regular HTTP connection. One TCP/IP connection uses a little resource (much less than a thread), and modern OS are optimized for handling a lot of concurrent connections: WebSocket and HTTP are just OSI 7 application layer protocols, inheriting from this TCP/IP specifications.

But, from experiment, I've seen two main problems with WebSocket:

1. It does not support CDN;
2. It has potential security issues.