Things have changed way too much in the bussines logic for our Flex 3 customer extranet application, so I have received the permision to make a fresh start... with low date pressure (I know, you envy me...).
Instead choosing the obvious Flex 4 path, it seems that Perl/Catalyst fits very, very well in this brand new scenary, but I don´t want to lose some goodies:
We have just ONE set of .swf modules, so all clients load the same actual files in a shared path.
They are Virtual Hosts.
Each domain directory has a index.php. It loads a personalization file with passwords AND the "real" shared index.php that loads the shared .swf.
No crossdomain problems because the .swf thinks that its in the true domain, thanks to the Apache virtual link.
All personalization inside the .swf (bussines data and visual prefs) are loaded dinamically from preferences in a database
It seems that I can do the same with Catalyst, isn´t it? Even easier, because I can make the perl app to respond "globally" to the same arguments in different vhosts, so everything can be decide at runtime
But the great advantage of Flex is that I have all the logic and preferences already loaded in the client, so the work in the server and the data transference is really, really low. The only data that travels is pure bussines data. No preferences, no pages, no nothing. And the app always know WHO the client is, so the queries are really, really clean.
So here are my two questions:
Is the Persistence in Perl/Catalyst a way to manage something similar?
I have read a lot of posts, here and there, about unclosed processes and threads, even cron programmed restarting of the server... as a "solution", and similar performance problems.
Must I manage such things to have a stable server?
It sounds ike a time bomb, and we are now very, very proud of our server perceived performance with a litle investment.
Thank you in advance
The nice thing about Catalyst is that it is very easy to plug all sorts of nice things from CPAN into your application. You need Authentication/Authorization, Session management, database handling, PDF generation, Excel parsing....? If you can think of it, someone on CPAN has probably done it already and published it for the world to use.
It is not exactly clear to me what you want the server to do. If it's just providing data to your SWF application through JSON or something similar, Perl Dancer (http://perldancer.org/) might also be interesting to look at, it's like Catalyst on a diet. Both Catalyst and Dancer have built in PSGI support allowing you to run it in any way you like.
Myself, I have just recently finished a project for ABN AMRO Bank Luxembourg in which I used Catalyst as the backend solution for an ExtJS application. The application is run under FastCGI and is extremely robust and stable. i don't know where you heard that Catalyst processes are leaky and need to be restarted, but that's just nonsense. Of course, if you program leaks yourself you might get yourself in problems, but the framework itself is very stable. Also, because of using Catalyst I was able to develop a very complex application is a very short time. I don't know how I could have managed it without Catalyst.
Good luck with you project
Rob
Related
I have been trying to decide if my web project is a candidate for implementation using PSGI, but I don't really see what good it would do for my application at this stage.
I don't really understand all the fuss. To me PSGI seems like a framework that provides a common interface between different Apache modules which lets you move your application between them. e.g Easily move your application from running on mod_perl to fastcgi, and provide the application support for running on both options.
Is that right, or have I missed something?
As I and the team I am a part of not only develop the application, but also pretty much do maintenance and setup of servers I don't see the value for us of being able to run on fastcgi, cgi, and mod_perl, we do just fine with just mod_perl.
Have I misunderstood the PSGI functionality, or is it just not suitable for my project?
Forget the Apache bit. It's a way of writing your application so that the choice of webserver becomes less relevant. At $work we switched to Plack/PSGI after finding our app running with very high CPU load after upgrading to Apache2 - benchmarking various Apache configs and NYTProf'ing were unable to determine the reason, and using PSGI and the Starman webserver worked out much better for us.
Now everything is handled in one place by our PSGI app (URL re-writes, static content, expiry headers, etc) rather than Apache configuration, so it's a) Perl, and b) easily tested via our standard /t/ scripts. Also our tests are now testing exactly what a user sees, rather than just the basic app itself.
It may well not be relevant to you if you're happy with Apache and mod_perl, and I'm sure others will be able to give much better answers, but for us not having to deal with anything Apache-related again is such a relief in itself. The ease of testing, and the ability to just stick in a Data::Dumper and see what's going on rather than wrestling with ModRewrite and friends, is a great boon.
Borrowing from a recent blog post by chromatic, Why PSGI/Plack Matters (Testing), here's what it is:
It's a good idea borrowed from Python's WSGI and Ruby's Rack but made Perlish; it's a simple formalizing of a pattern of web application development, where the entry point into the application is a function reference and the exit point is a tuple of header information and a response body.
That's it. That's as simple as it can be, and that simplicity deceives a lot of people who want to learn it.
An important benefit is, ibid.,
Given a Plack application, you don't have to deploy to a web server—even locally—to test your application as if it were deployed … Plack and TWMP (and Plack::Test) use the well-defined Plack pattern to make something which was previously difficult into something amazingly easy. They're not the first and they won't be the last, but they do demonstrate the value of Plack.
Started wrote an answer and after 50 lines I deleted it. Simply because it is impossible tell (in short) why is PSGI extremely cool. I'm new in PSGI too, but zilion things now are much easier as before in my apache/mod_perl era.
I can give you next advices:
read the Plack advent calendar - all days, step-by-step. You must understand the basic philosophy, what is good on onions and so on... :)
search CPAN for "Plack::Middleware::" - and read the first few lines in each. Here are MANY. (Really should be somewhere some short overview for each one, unfortunately don't know any faster way. Simply it is good to know, what middlewares are already developed. (For example, you sure will need the Plack::Middleware::Session, or Plack::Middleware::Static and so on...)
read about Plack::Builder (already done, when you done with the advent calendar) :)
try write some apps with it and will find than Plack is like the first sex - now you didn't understand that you could live without it.
ps:
If was here something like "Perl Oscar", will sure nominating MyiagavaSan. :)
The only place where I found informations on G-WAN web server was the project web site and it looked very much like advertisement.
What I would really know is, for someone who is proficient with C, if it is as easy to use and extend that other architectures. For now I would mostly focus on scripting abilities.
Are C scripts on GWAN easy to write ?
Can you easily update and upload new C scripts to the server (say as easily than some PHP or Java pages on other architectures) ? Do you have to restart the server when doing so ?
Can you easily extend it with third party or existing C libraries ?
Any other feedback welcome.
Well, now G-WAN is available under Linux, I am using it for more than 6 months.
The C scripts are fully-ANSI C compatible so there is no difference for any seasonned C programmer.
To update them on the server, you can edit them directly in the /csp folder (remotely via SSH) or locally on a test machine (and copy them later): G-WAN reloads scripts on-the-fly when they have been changed on disk (no server stop required).
G-WAN C scripts can use any existing library (starting with all those under /usr/lib) without any configuration or interface: you just have to write a '#pragma link' followed by the name of the library at the top of your script.
What I found really useful is the ability to edit C scripts and refresh the view in the Internet browser to see how my code works.
If there is a compilation error, then G-WAN outputs the line in the source code (just like any C compiler).
But where it enters the extraordinary area, is when you have a C script crash: here also it gives you THE LINE NUMBER IN THE SOURCE CODE (with the faulty call and the backtrace).
Kind of black-magic when you are used to Apache modules.
My experience with G-WAN and its C scripts are:
The G-WAN community is very small. Questions you have are mostly answered by its single developer.
I consider the API not mature: it's not as "clean" as Java APIs.
The limitation, but at the same time the power, of C: it's a systems programming language. So writing application logic in it must be done carefully.
You generally need to be a good developer to get good results: if you do something wrong, the server crashes fast and hard (Unix-style).
I've written some scripts now, to try out G-WAN. Overall, it's been very "productive": not much bugs and it works if you follow the guidelines and don't want to do too much funky stuff you expect it to have, like mature web servers. However, I have got the feeling I'm reinventing the wheel a lot of times.
G-WAN also support scripts written in other programming languages (C++, Objective-C, Java, etc.) so you will benefit from whatever native libraries each language implements.
For C scripts, well, the /usr/lib directory lists more than 1,500 libraries that G-WAN can re-use with a simple #pragma link "library".
I found it neat to be able to write a Web application with a part in C, another in C++ and a third one in Java!
Benchmark shown how G-wan fare poorly at handling these tests.
http://joshitech.blogspot.sg/2012/04/performance-nginx-netty-cppcms.html
I have been using G-Wan for about two years. I consider it highly stable and production ready for static files. I have a number of static sites running for over a year with no issues.
I have built some small scale dynamic sites in C with it as demos/test projects. A bittorrent tracker and a real time analytics platform both using the KV Store for data backing.
In my view building large scale dynamic sites in G-Wan is possible but only with a significant investment in development and support. G-Wan is better suited to building robust highly scalable "enterprise grade" applications than tossing something together over a weekend.
I use G-Wan for a CMS http://solicms.com but for now, I use Ruby as primary language.
I have used G-wan for some preliminary testing and it does benchmark well. I have found a few points of concern that make it so that I will not likely use it for any of my projects. I have found that it seems to cache responses for about 0.5secs to speedup the responses/second and I can't have only some of the responses hitting the application code. Also the key/value store is great for cache and temporary data storage but I'm not sure how well it will work as a real back-end storage method.
I learn best by taking apart something that already does something and figuring out why decisions were made in which manner.
Recently I've started working with Perl's CGI::Application framework, but found i don't really get along well with the documentation (too little information on how to best structure an application with it). There are some examples of small applications on the cgi-app website, but they're mostly structured such that they demonstrate a small feature, but contain mostly of code that one would never actually use in production. Other examples are massively huge and would require way too much time to dig through. And most of them are just stuff that runs on cgiapp, but isn't open source.
As such I am looking for something that has most base functionality like user logins, db access, some processing, etc.; is actually used for something but not so big that it would take hours to even set them up.
Does something like that exist or am i out of luck?
CGI::Application tends to be used for small, rapid-development web applications (much like Dancer, Maypole and other related modules). I haven't seen any real examples of open-source web apps built on top of it, though perhaps I'm not looking hard enough.
You could look at Catalyst. The wiki has a list of Catalyst-powered software and there are a large number of apps there - poke around, see if you like the look of the framework. Of this, this is Perl, so some of those apps will be using Template::Toolkit, some will use HTML::Mason... still, you'll get a general idea.
Try looking at Miril CMS. Although I don't know in which state it is.
I am the same with code, and had the same request. When I did not find a solution I created my own. which is https://github.com/alexxroche/Notice
I hope that it is a good solution to this request.
Notice demonstrates:
CGI::Application
CGI::Application::Plugin::ConfigAuto
CGI::Application::Plugin::AutoRunmode
CGI::Application::Plugin::DBH
CGI::Application::Plugin::Session;
CGI::Application::Plugin::Authentication
CGI::Application::Plugin::Redirect
CGI::Application::Plugin::DBIC::Schema
CGI::Application::Plugin::Forward
CGI::Application::Plugin::TT
It comes with an example mysql schema, but because of DBIC::Schema it can be used with PostgreSQL, (or anything else that DBIx::Class supports.)
I use Notice in all of my real life applications since 2007. The version in github is everything except the branding and the content.
Check out the Krang CMS.
I’m scoping a new software project and haven’t had much experience with software development. This is a multipart question.
What are some recommended books for web application architecture?
We are basically looking to develop several front end applications (mobile and websites) that can query a central application pool that’ll hit our backend database to retrieve the data. Is there a name for this kind of architecture?
The problem with software development (like most things in life) is that there are so many choices and so many opinions. I would get help from someone with experience and references. Find someone/company that has done something similar. You should also go to any computer store and search around for books on similar architectures (since your tags show iphone, webservices, andriod - there are tons of books out there).
After you get someone to give you advice on the architecture make sure you ask about cost, time, and seeing results frequently.
What are some recommended books for web application architecture?
That depends on the design pattern you will use. MVC (Model-View-Controller) is a good pattern. The Model is the database, Controller is the middle between the other two (where all the business and logic is), and View is what you see in the browser.
There is no one answer as to what MVC should you use. For example you can choose MySQL as the Model, Java Servlets as the Controller and jQuery for View.
We are basically looking to develop several front end applications (mobile and websites) that can query a central application pool that’ll hit our backend database to retrieve the data. Is there a name for this kind of architecture?
Depends on your platform, if you are on Windows then WAMP is a good place to start from, it already has Apache application server, MySQL database, and PHP.
If you already know some HTML, look into PHP. It's not a good language but it gets the job done, it's free, and it gives you a lot of flexibility in getting your idea up and running.
I don't know though, "I don't have much experience in software development." You're going to have your work cut out for you. You will need to know the basics of programming, the basics of HTTP, working with databases, and maybe even some system configuration. You might be getting in over your head.
To answer #2 though - one name you'll commonly see is LAMP - Linux/Apache/MySQL/PHP. Some people sub out some of those things for something else (for example, Python for PHP) but in essence it means a free application stack.
If you were going to start building web sites as a consulting business on the side -- keeping your day job -- and you also had a toddler and a wife, what frameworks/tools would you pick to save you typing?
Any language.
I'm looking for a productivity superstar stack that won't tie my hands too much when I have to update the site 6 months later, or "evolve" the data model once in production.
It needs to allow me to say "yes" to the client: community features, CMS, security, moderation, AJAX, ...
I would suggest Django. Super simple to get something up and running really quick. You are using Python which has a large library to go with it. For me Ruby on Rails would be a close second.
I'd probably look at DotNetNuke. Its easy to set up (a lot of hosts will do it for you) and easy to use and put together a custom site that business's will be able to maintain in the future.
Its fairly easy to create custom modules that are specific to a business and hundreds of modules for sale (or free) that can be integrated into DNN for special uses.
Take a look at Microsoft's Sharepoint server if you'd like a pre-made framework with many options for plugging in your own code. Sharepoint is kind of a world unto itself but it is a very powerful environment.
Update: I'm surprised to have been voted down on this one. Keep in mind that the questioner specifically requested frameworks that included a CMS. Sharepoint meets this criteria - unlike straight .NET or other web development frameworks.
If you are going to vote the entry down, I think you owe it to the person who asked the question to explain why you don't think he should not even explore it as an option. You could be right - collective wisdom is what voting on SO is all about. But without an explanation, we don't know why you think you are right.
My answers are going to revolve around the .NET stack.
Use Master pages and CSS templates. This makes it so much easier to pop in a new look and feel for your customer.
For sure I'd include the Dynamic Data framework in the .NET world.
Hosting might become an issue for your customer. Questions around managing email addresses, procedures on how to quickly update the website to include the new contact phone number (different for each customer, I'd assume) Consider getting a reseller account on your favorite webhost, and dole out webhosting accounts as appropriate. There are lots of issues around this point. It may turn out to be a nice source of recurring revenue.
Build yourself a few patterns including a database wrapper which would handle all your data calls (i.e. a dll which wraps all your data calls, sets up your ADO.NET objects, runs your sproc calls, and picks up the connstring from app.config or something similar.)
This goes a long way to maintainability as well.
I would recomend going with anything MVC in a language you can undertand! Theres a couple of CMS's in python, php and ruby using that design and well... that allows you to be ready for combat for Ajax and expanding anything very fast.
This is definitely not a question that can be answered.
I prefer asp.net webforms because I think it allows for extremely rapid web app development, but I am sure you will receive recommendations for:
asp.net mvc
Ruby on Rails
PHP and some framework
Python and some framework such as Django
I believe PHP has the most pre-built apps that you can use, though asp.net also has the things you are looking for.
All of these platforms and frameworks can do what you want.
Choose between Rails and Django. They both have different strengths. I like Rails better in general, but Django's admin interface can save you a lot of time when you need it.
There's another factor to take into consideration here: what are you the most familiar with? I believe that some studies have found upwards of a 30% loss of productivity when trying to learn a new language/framework.
Sometimes, there's nothing wrong with just sticking to what you know. But if you're interested in what languages/frameworks to learn, I'll refer you to the other posts because the above was the only thing I really have to add.
I recommend looking into Grails. It uses Groovy which is similiar to Java (so if you know this already you're good to go). Groovy runs on the JVM so you can still use all the great libraries already available for Java. Yet, since it's a dynamic language with a lot of the similar bells and whistles like Ruby you can use closures and that kind of neat stuff when you need/want to. And you're not slowed down by Java's traditonal slow compile-deploy-test development cycle.
Grails is already setup with Hibernate and Spring. You can create CRUD application in practically no-time (pretty much like Rails applications), and at the same time drill down and be able to control every little details since it's built on such proven and well-supported technologies. In addition there's literally hundreds of plugins available that helps you easily set up things like mailing lists, security, AJAX components and so on.
Otherwise, if you want to set up a community site and don't want to code a single line you could always check out ning.com.