Real time web based client for delphi app. HOWTO? - delphi

First of all what I want is quite complex, at least for me, but on the other hand it sounds exciting.
I have a software written in delphi, and I want a real time web based client for it.
The requirements:
On the client side pure Javascript
Shiny interface ( GWT, SmartGWT )
Asynchronous connection between the server and the client. Ajax push, Long Polling, Comet, WebSocket?
On the server side
scale-ability
On the delphi side I think I could use ICS from Overbyte, to handle the requests. I know that THttpAppSrv from ICS pack can easily serve simple content, but what about Websocket, or how can I do long polling with it?
What do you think, is it a good combo ( GWT, SmartGWT on the client side, and ICS on the delphi side ), is there any sample project out there, or is there any other solution?
Update
Thanks for the useful comments, I think I get closer to the solution. It's good to know that GWT can use a custom server, however I think Arnaud is right, GWT with it's own Jetty server is a complete solution, but unfortunately not for me. :) I think I need a server written in delphi, which can communicate with GWT RPC.
Update 2
I accepted Arnaud Bouchez's answer which looks me the best for the original question, however I think there's a better solution (if you change the requirements a little) for creating a client running in the browser for a delphi application. I just make a little comment here, to share the idea. Finally I used a node.js server, and connected it to my delphi app with the help of ZMQ.

About the HTTP server on the Delphi side, consider using the kernel mode http.sys server provided by Microsoft since XP. Should be faster than ICS.
For the AJAX part, take a look at Op4JS or up to come ElevateDBBuilder.
What is great with those solutions is that you can write object pascal code, and that this code will be translated to JavaScript. Not yet finished, but worth waiting a little for their release time.
Of course, more classic AJAX solutions do exist, like IntraWeb or ExtPascal. Both implement their own web server.
About GWT, AFAIK they are java libraries, deeply linked to the Java world. You won't be able to make it work with Delphi.
Edit about GWT:
GWT is a full Client-Server framework.
If you go with GWT, I suspect you'll end with a full Java rewrite of the application at some point. Or you'll miss most interest of GWT as a framework. It's your choice.
I'd rather rely on some more standard approach, using JSON for communication for instance as we do with our framework.

Have you checked out Intraweb? I have not used it extensively myself - but it seems to be quite popular for Delphi web apps.
I have made several Web Apps using TWebBroker with either IIS or Apache. It is Asynchronous, and allows you to easily port/share Delphi code with your other application. And it would support Ajax calls.

Delphi, pure javascript on client side and shiny interface? You're talking about Unigui!

I worked on PHP, ASP and Cold Fusion before, and wanted to do (almost) the same with Delphi. I started xxm. It has Delphi and HTML code in the same files, and (re)compiles a library when you hit refresh in a browser. I've made handlers for these libraries so you can run them in IIS, Apache, InternetExplorer, Firefox, or straight from a Delphi-based HTTP implementation. (I started work on a http.sys handler also, but that'll take a lot more work.)
Also, in relation to your question, I wanted streaming, I wanted that what I output would get transferred ASAP to the listening client, so you could do long running pages, long polling, and the like. As for GWT and other client-side script, I've successfully used prototype and jquery.

Related

Which would be fastest and most secure among FastCGI, ASP.NET MVC and Web forms for Server Applications

I have to build an Automated Chat Application which will have it's front end as a widget on the website and back-end logic at server. It's main purpose will be to provide an interface to the customers to solve their queries with a chat personnel sitting at a location with the server as the communication point. If there is no person available then the application will parse the string and try to give a few answers by checking among a database.
I have a very good experience in C++ and a little experience in Java. The main concerns of the application are source code security and highest efficiency.
The restrictions which i am facing from the server side is that i have to run it on IIS and the only scripting languages supported are PHPv5, ASP, ASP.NET and FastCGI.
I am not going for PHP since i have found from googling that it's possible to reverse engineer it and it will take me a lot of time to learn a new language, so a strict no.
I prefer going for FastCGI cause it will serve exactly what my requirements are, but i am unable to find a way to compile on windows with C++ or any good tutorial. Most of the results i found on google related to FastCGI development were about Linux or in Perl for windows. I am also unable to find a way as to how to compile it on windows platform.
I am now being forced to go for ASP.NET, which will be my last option since it's an Interpreted Language and Interpreted languages have a tendency to be weak against reverse engineering.
So can anyone suggest me how to go about with it. If there is no way out for FastCGI then suggest me which will be good amongst MVC and WebForms for the given situations. I am new to both of them and i need to complete the application within two weeks.
First things first.
EVERYTHING can be reverse-engineered. It just depends on how smart the guy trying to reverse engineer your code is. Obfuscating is not a replacement for securing your code. If your server side PHP is safely stowed away on your server with all the proper security parameters configured, then you have nothing to worry about. But if you don't know PHP already then fair enough.
ASP.NET is only partly interpreted. The C# or visual basic that you use for the server side code is compiled. What IS interpreted is the code directly on the page. Remember though that most of your logic does not take place there... it takes place in the code pages which are compiled and the page code is mainly for displaying what you have already calculated. But don't forget that any server side tags that you put into your HTML on your pages get parsed and stripped out when the page is served to the user. If you have a tag <%: ViewData["value"] %>, the user will only see the value for "value" when they look at your source, and not the actual server side tag.
You are going to have a tough time learning ASP.NET AND completing your app in two weeks. I personally love ASP.NET MVC, but if you don't have much of a web programming background then it probably isn't the easiest thing to learn in comparison to Web Forms. That said however...
I'm not a fan of PHP, but it is widely used and a great language for setting up simple projects quickly. There are also tons of examples out there and it is of the first web languages that people learn (in part for those reasons). If you have two weeks to learn a language and set up a project, go with PHP. Even with a C background, there is a lot more to web programming than just knowing a server side language, so you'd be best off a quick and dirty language that gets what you want to get done, done, with minimal effort. That is to say, PHP.
FastCGI / C++ has a better performance. If you need a link on how-to: http://cgi.sourceforge.net/ and much more with google search.

Is DataSnap an appropriate solution to bring the data and business logic of an existing Windows app to mobile/web clients?

I need to take a huge Delphi XE application (backed by proprietary SQL server NexusDB) and begin providing my clients the ability to access the system in new ways:
Thinner Windows client for slow/VPN connections
Mobile/Tablet
Web
DataSnap appropriate for this or is introducing a middle tier the wrong way about providing remote/mobile access? Other solutions/ideas welcome.
(I have XE2 Enterprise but am stuck on XE Enterprise for awhile.)
DataSnap is being aggressively positioned by Embarcadero as a Multi-platform connectivity solution, where servers are written in Delphi, and mobile connectors are available (in XE2 and later) for a variety of mobile device platforms. So the quick answer is yes, it is suitable in general.
Is it suitable for you? You haven't said much that would help me answer that question; You are willing to buy Enterprise or Architect SKUs of Delphi, so I would guess yes.
If it was me, I'd look for a solution that implements a pure simple REST architecture that is available to every system out there, mobile or otherwise, no matter what language or platform, but I haven't got a suggested alternative because it seems to me that SOAP is nearly dead and that there is no universal replacement technology out there that does everything that soap client/server systems do. I'd be tempted to consider "roll your own REST+json" or evaluate Remobject's product offerings too, and select a path that makes sense for you, from a business and technical point of view.
Datasnap is fine, but it's not the only option. It's probably the simplest and most easy to roll out option currently available, and the only one "out of box" ready to go in XE2 if you want apple, android, and a few others, right away.
That depends on your security needs, and the way you're providing data to clients. As I often pointed out, dbExpress-Datasnap has big security flaws (while the DCOM version is not well suited outside a LAN, and does not offer out of the box mobile devices support).
A web application would have less issues because the datasnap-web server connection would be probaby internal, it would be up to the web application to ensure data protection.

How to do a REST webserver with Delphi as a backend for a big web application?

I read this question but was somehow not satisfied with the answers.
I also quickly read (as suggested in that question) the last chapter of Marco Cantù 2010 Handbook, from which I quote the following (I think I can quote such a short text):
I [Marco Cantù] do have a lot of
investment in server side web and REST
applications written in Delphi, and in
the recent years I've started playing
with and introducing at conferences a
Delphi Web Application REST
Framework119 (that is, DWARF), which
at this time is still not publicly
available... simply because it is too
sketchy and unfinished to be
published. I've seen other ongoing
efforts to clone Rails in Delphi and
offer other REST server architectures.
I think that if you want to build a
very large REST application
architecture you should roll out your
own technology or use one of these
prototypical architectures.
Considering that I own Delphi XE Professional and DataSnap is not in there and I would like to consider to write large applications too according to the above comments it seems DataSnap is not an option.
Is there even a commercial solution for this? I don't want to consider "my own implementation of REST", I would like to create a webserver that uses some of my datamodules where I use the DAC I choose (Devart in this case).
Final note: my goal is to write the backend for a large web application, on the client I would like to use Ext JS 4.0, but I want to do all the client work in javascript, to take full advantage of EXT JS, so basically I need a webserver just for the data and tracking the state, not for serving webpages.
To create your REST services, try our Open Source mORMot project. Now it is a well known and stabilized project, used world wide in production.
You can use any DAC with the current state of the framework by implementing a custom TSQLRestServerStatic class (similar to the TSQLRestServerStaticInMemory class, but calling your DAC): so you'll benefit for the ORM and the JSON RESTful architecture, together with the high-speed http.sys kernel-mode server.
The SQLite3 engine is NOT mandatory with our framework, even if it was designed to work better with it.
If you will start an application from scratch, I think the mORMot is a good option if Delphi is your only option. If you choose datasnap you'll have to live with the problems of performance and stability.
I wrote an article on my blog talking about performance and stability with DataSnap (and mORMot) in large applications, you can see it on the following link:
DataSnap analysis based on Speed & Stability tests
I think you should have a look at kbmMW, there is a way to implement a basic REST server based on an event driven HTTP server.
Check news.components4developers.com news groups, there you will have a lot of documentation.
FireHttp is a high-performance Web server based on Delphi/Object Pascal language. It supports HTTP 1.1, HTTPS (SSL/TLS), WebSocket, GZip, Deflate, IOCP, EPOLL. It adopts multi-process+multi-threading model, has good stability and concurrency performance, and provides SDK source code. Developers can use SDK to quickly build high-performance cross-platform Web applications.

What are the current choices for Delphi Web & Web Service Development

I'm toying around with Delphi. Most of my desktop development is done in .Net, and embedded systems with C. I've done some web development in RoR & Python (Django, CherryPy) I am interested in taking a crack at a project that would be a web service (REST or SOAP) with a native client and a web client.
Because I've recently been re-inspired to learn Delphi, I'm curious what the options are to build the web service and web client with Delphi. Most of the Delphi documentation is a little dated but so far I've found these choices:
DataSnap
WebSnap
WebBroker
IntraWeb
Data Abstract and RemObjects SDK from RemObjects
I get the impression that WebSnap is dead, but the other technologies are still being developed. Is there any guidance about which technology to investigate?
p.s. I realize that Delphi isn't a wildly popular choice for web development, but I'm curious to try since I've been having fun learning the VCL.
You could perhaps add our Synopse SQLite3 Framework to your list.
There is some interresting features:
ORM approach to manage your data (i.e. define and access your data as regular Delphi classes), on both Server and Client Side - similar to ActiveRecord in RoR ;) ;
Multi-tier architectured;
no database or dll to deploy (uses embedded SQLite, without any external dll) - you can even not use SQLite, but a simple and fast in-memory database written in pure Delphi (I've begun a fork of Zeos, to be database independent);
Very optimized HTTP/1.1 multi-threaded Server (but you can communicate via other protocols, or even purely locally within the same process, without any Client/Server);
Data transmission uses standard JSON, so you can receive the same data in either a Delphi client, either an AJAX client;
Client/Server is RESTful and written in very optimized Delphi code (some part were even written in asm after profiling, for speed and low memory use);
Can also be used to define DataSnap-like Client-Server JSON RESTful Services, if the RESTful approach is not enough for you;
Full Open Source, compiles and work from Delphi 6 up to XE (with full Unicode support for all versions, because it's based on UTF-8 from the engine core).
Web Service Toolkit is a web services package for FPC, Lazarus and Delphi; “Web Service Toolkit” is meant to ease web services consumption and creation by FPC, Lazarus and Delphi users. Better check out from svn as the 0.5 release is actualy outdated.
RESTful server side method calls hosted as an ISAPI dll or just use the Indy HTTP Server component. It's really a quite simple and powerful approach and lets you get started quickly without a big learning curve.
DelphiMVCFramework is a powerful RESTful framework used also for website development
https://github.com/danieleteti/delphimvcframework
DMVCFramework features
RESTful (RMM Level 3) compliant
Fancy URL with parameter mappings
Server side generated pages using Mustache templates
Messaging extension using STOMP and Apache ActiveMQ or Apache Apollo (beta)
Can be used in load balanced environment using Redis or MySQL as state server
Integrated RESTClient
Works with DelphiXE3 or better
Integrated Logging System
It is really simple to use. You can be productive in minutes!
Here's the DMVCFramework Developers Guide
https://danieleteti.gitbooks.io/delphimvcframework/content/
If you need support, there is the official facebook group with more than 600 users https://www.facebook.com/groups/delphimvcframework/
I'm the main developer but there are more than 6 active contributors.
WebHub is another well established, though lesser known third party Delphi web framework.
Couple other choices that can be used to build a webservices server, somewhat simlar to datasnap or remobjects/dataabstract, are below. I did some work years ago with kbmMW and it's a solid library. I think both kbmMW and RealThinCLient have free and/or open source versions:
RealThinClient
kbmMW
We have a web front end for our Delphi server app written in Delphi Prism/ASP.NET. It works great and allows us to leverage our Delphi language skills in a .NET environment.
This one is very old,but a lot of things have changed,I myself had left Intraweb and gone to UNIGUI,since its based on EXTJS and produces single page applications.
Well Its been two years since I left my last message on this posts,
although uniGUI is still the only solution already made for creating SPA in Delphi,it seems that IW17 will be a real cutting edge,an waters divisor in the history of Delphi.Client side rendering without needing server communication,Wordpress integration,no need to write a single line in javascript like other frameworks,websockets,fibers,our "Delphi React".

How is the best way to write a SOAP 1.2 Client with Delphi Win32

So far, no Delphi version supports SOAP 1.2 clients or server.
I have tried for weeks to make it works, but every time a new problem, with VS/C# I could do the same, and make works in 3 days, but I need to do with Delphi 2009.
"I write a new version using Rem Objects SDK,", but the result was not better that I had with Delphi SOAP library.
But I'm wondering what choice else do I have, which library/component full support SOAP 1.2?
I found a message from Bruneau, suggesting Pocket SOAP
http://www.pocketsoap.com/pocketsoap/
I don't know how this works, Ill investigate and see what I can do.
Remember to vote for SOAP 1.2 support on codegear's QC:
http://qc.codegear.com/wc/qcmain.aspx?d=66864
Currently, it's voted the #2 report for Delphi (after 64bit support). I'm really sure that CodeGear is not going to ignore this.
Follow up. This has been implemented in Delphi 2010.
I suggest that you dig into the source. With Delphi 7, I was able to add all sorts of extras by copying the SOAP code into my app's folder and editing it carefully. In one case I did some string manipulation to adjust the incoming SOAP packet to make it work with the way Delphi worked. I've not had to do this with RemObjects yet, but you do get the source for that too. Plus they have active newsgroups you can ask questions on.
In some cases I found it much easier to write a proxy SOAP service in C# and VS, and consume it from Delphi with a simplified service description (WSDL). In the long term it was the most efficient solution, without any problems regarding stability or performance. The SOAP support in Delphi is not one of its highlights.

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