Aug 20, 2013

ADempiere: How To Use Scala For Customisations

"Scala is becoming an increasingly popular language and for many companies/developers it's a superior alternative to Java. ADempiere open source ERP/CRM, is written in Java but since Scala runs on JVM and has very good Java interoperability, it's very easy to customise ADempiere with Scala.

We'll see how it can be done."

Read the full article on my website.

Aug 14, 2013

Grails: How To Secure Your Application Using Spring Security Core

"Any web-based application must have a mechanism for authentication users and authorising them to do their defined activities in the system. One can go for the traditional approach of doing it with a login form; it works for the start. But on today's Internet, a classic pair of username and password is not always available as many people prefer to use a single OpenID, Twitter or FaceBook account to access their data across different web sites. Also in corporate environments usually authentication and authorisation is done against an LDAP database.

This is where Spring Security collection comes to play by allowing you to connect to a wide range of data sources and acquire access information from them instead of storing them yourself."

Read the full article on my website.

Jun 8, 2013

A New Platform For Business Application Development

"Anybody who has been involved in developing a business application, has already exhausted the long list of frameworks/libraries in JVM, .NET and Python platforms searching for something that reduces the costs while increases the development speed. However it's almost proved to me that one should seek the answer in less explored/popular platforms. Let's meet Pharo!"

Read the complete article on my website.

Feb 1, 2012

Setup The Ultimate Development Environment: Emacs, Clojure, Leiningen and Git

Clojure is a wonderful language.  And Emacs is an unbelievably powerful editor beast which you can easily get addicted to after you have tamed it.
However it's not easy for a newbie to customise Emacs to her needs.  I'll show you how to setup a full development environment for Clojure in Emacs with Git integration, Javadoc lookup and Leiningen powerful build tool for Clojure.  My examples will be for Ubuntu family (Ubuntu, Xubuntu, Kubuntu, Lubuntu) but you can easily use the idea for the Linux distro you use.

  1.  Install Emacs
Piece of cake! Fire up the terminal and issue the following:
$ sudo apt-get install emacs23
  2.  Install Leiningen
For a complete guide please see Leiningen on Github.
Download Leiningen installer script and put it in a directory.  I personally, have a Programs directory in my home; so I put the script in /home/bahman/Programs/Leiningen.  Change the permissions of the script to be executable either using your favourite file manager or using command line as below:
$ chmod +x DIRECTORY_YOU_HAVE_PUT_THE_SCRIPT_IN/lein
 Now at the command line, cd to the directory you have put the script in and run
$ ./lein self-install
and wait a short while for Leiningen to download the needed JAR files.

   3.  Install Slime
Now it's time to download Slime.  Remember that you cannot use the version shipped with your distro.  Only a specific version of Slime works with Leiningen.

At a command prompt run
$ git clone https://github.com/technomancy/slime/
and then copy the slime directory which git just created to the desired place.  Again, I put it under /home/bahman/Programs .

Now open ~/.emacs in your favourite editor and add this at the end of the file:
(add-to-list 'load-path "PATH_TO_SLIME/")
(add-to-list 'load-path "PATH_TO_SLIME/contrib/")
(require 'slime)
(slime-setup '(slime-fancy))
(slime-setup '(slime-repl))

  4.  Install Elpa (Emacs package manager)
For a more complete guide see Elpa installation guide.
Run Emacs.  In the *scratch* buffer type this
  (let ((buffer (url-retrieve-synchronously
        "http://tromey.com/elpa/package-install.el")))
  (save-excursion
    (set-buffer buffer)
    (goto-char (point-min))
    (re-search-forward "^$" nil 'move)
    (eval-region (point) (point-max))
    (kill-buffer (current-buffer))))
then press ALT+x and type eval-buffer.



Close Emacs.  Open ~/.emacs.d/init.el in your favourite text editor (create the file if it doesn't exist yet) and  paste this in the file to add Marmalade package repository to Emacs.
(require 'package)
(add-to-list 'package-archives
             '("marmalade" . "http://marmalade-repo.org/packages/"))
(package-initialize)
Open ~/.emacs too and add this at the end and save it.
(when
    (load
     (expand-file-name "~/.emacs.d/elpa/package.el"))
 (package-initialize))
Run Emacs.  Press ALT+x and type package-list-packages and hit ENTER.  A list of packages that can be installed is shown.  Navigate to a package named clojure-mode and press i followed by x.  Voila!  It's done!

  5.  Test Your Installation
At a command prompt (assuming you have added ~/.lein to your $PATH and have cd'ed to the desired directory) run $ lein new myproject.  Run Emacs.  Press ALT+x followed by cd.  Now enter the directory of the project you just created with Leiningen and hit ENTER.  Now type ALT+x again followed by clojure-jack-in.  If you get a warning about Slime version (just ignore it), this means that you have setup everything correctly so far.




  6.  Git Integration
If you haven't installed Git yet, run this at the command prompt to do so
$ sudo apt-get install git
 We'll use Egg for integration of Emacs and Git.  Clone the Egg repository like this
$ git clone https://github.com/bogolisk/egg.git
and copy the egg directory to ~/.emacs.d


Open ~/.emacs in your favourite editor and add this to the end of it
(add-to-list 'load-path (expand-file-name "~/.emacs.d/egg"))
(require 'egg)
Restart Emacs and it's all done.

  7. Javadoc Lookup
This is a real handy and neat feature: browsing Javadocs inside Emacs!

Fire up Emacs, press ALT+x and type package-list-packages followed by ENTER.  In the packages list, navigate to the package named javadoc-help.  Type x followed by i.  After the package is installed.  Open ~/.emacs in your favourite text editor and add this to the end of it to enable javadoc-help.
(require 'javadoc-help)

By default, javadoc-help opens the documentation pages in the default desktop Browser which is probably the almighty Firefox.  But it's better to read and navigate the docs inside Emacs itself.  To do so, you need to install a console-based browser named w3m and its Emacs interface.
$ sudo apt-get install w3m w3m-el-snapshot

Now let's configure Emacs to use w3m for browsing.  In Emacs, press ALT+x and type customize-variable followed by ENTER.  Then type browse-url-browser-function followed by ENTER. In the customisation buffer that just opened change the value of the "Value Menu" drop-down to "Your own function".  Then in the box in front of it type w3m-browse-url.  Then press both "Set for current session" and "Set for future sessions" buttons (make sure they are pressed!) and then press "Exit".






By default javadoc-help loads documentations from the internet but if you're on a slow connection like me, that's not an option.  To tell javadoc-help to load them from your hard drive, in Emacs press ALT+x and type javadoc-help followed by ENTER.  In the javadoc-help buffer press f and type the path to the local javadocs "api" directory and then press CTRL+g.

That's it!  From now on, anytime you need to check the documentation for a class just press ALT+x and type javadoc-lookup.

  8.  Final Word
You just setup your Emacs to become a powerful Clojure development environment.  But that's not all.  Emacs has many many more features which you can start to get your hands on by reading its comprehensive help pages.  But first start by reading Emacs Tutorial from the Help menu :-)

  9.  Stay Tuned!
I will share some of my useful customisations of Emacs, in a different post soon.

Apr 25, 2011

What is ERP?

No matter if you're an excutive office, IT consultant, software developer or a business manager, you've heard people talk about ERP in meetings and sessions.  And probably a half-dozen of ERP providers have already come knocking at your office door to present their products.

No doubt that you have spent hours searching the internet on what exactly is an ERP and how can it help an organisation.  But if you're still in doubt, this writing may help you.  I'll try to explain the golden characterisitics of an ERP in a simple language; so please bear with me.

The Definition
ERP is an integrated, business process oriented and best practice based information system that helps managers better understand the situation of their organisations.

So a software that is called an ERP is:
  1. Intergrated
  2. Business process oriented
  3. Best practice based
and its ultimate goal is to help managers make more efficient decisions.

Integrated (Data)
In an integrated software, what one user does in a organisation can be immediately seen in another organisation by another user.

For instance, in a trade firm, as soon as a purchase invoice is entered and approved, it may immediately effect the product cost and accounts payable and change the P/L.  In such a system, when receiving a customer payment, the finance user can instantly check for which invoice this payment is happening and what are the payment terms.  Upon entering and approving the payment, the customer's receivables decreases and at the same time the sales staff may be notified.
Figure 1: Sample Integrated Information System (note that there is only one place to store/retrieve data)

The subtle point is that those series of events take place without requiring an administrator.  In other words, it is easily and flawlessly possible because all the software data resides in a single logical place and there is no clutter.

Business Process Oriented
From ERP point of view, the performance of your organisation is the result of execution of several business processes each of which covering a slice of your organisation and involving different layers of that slice to do the job; just like a slice of cake which cuts through different layers of the cake.

For example, in a trade firm, the sales business process involves sales, finance and procurement (if needed) departments and in each of them one or more users or organisation roles play a key role in performing the process.  Look at figure 2:

Figure 2: An exampe of business process oriented view of organisational perforamnce
As you can clearly see, sales business process involves the whole organisation in worst case.  If we look closely, we can understand how being integrated helps; for example a requisition is created based on sales order, a purchase order is created based on the requisition and purchase invoice is issued as a consequence of a sales order and all the links of this chain of actions are stored in one logical place, meaning that there is no need for any extra action from the staff; they just need to do their job which is running the process.

Now look at figure 3:

Figure 3: Information back-link in ERP

As a result of data integration and mapping organisational performance to business process execution we have a consistent chain of documents which enable us to accurately find out the reason/root of any organisation acitivity at any given time.

Best Practice Based
It is possible that a software taking advantage of a good design reach the above characteristics.  But in that case, still there is something missing to enable the software to help managers in the best possible way: best practice knowledge.

What distinguishes ERP from myriad of softwares claiming the same achievements, is extensive amount of best practice used in its design and configuration; meaning that ERP offers you the most efficient strategies -which have been tested in real life by prominent firms- to manage your organisation.  In fact, from this point of view, ERP is the medium to transfer the optimum management strategies/techniques from successful and well-known firms to others.

This characteristic is vital to an ERP as the only idea behind an ERP is to help managers, manage their organisations better and that is not possible without using optimum strategies.

Helping with Optimum Management
You may wonder why a software company would bother spend considerable amout of money, take a lot of risks and create a software with all the above characteristics?  And why a business manager would think of implementing such an expensive and giant software?

There is a simple rationale:  approaching optimum organisational management.

After a successful implementation, a manager is able to analyse her organisation's performance and accurately find out its weaknesses and strengths and decided how to imporove or use them.  And that is what a manager should do: making decisions.

By handling all the complexity of an integrated data flow, simplifying access to organisational performance information and offering the manager with accurate and up-to-date information, it enables the manager to concentrate on analysing and decision making without wasting her own and her staff's precious time dealing with technical details and report preparation headache.

Consequences
Let's suppose you have successfully implemented ERP in your organisation and it's running smoothly.  What are the benefits for you (as a top-level manager)?

  1. ERP integrated data model makes activities more transparent and enables users to access their required information at any time in a real-time manner.  The sales officer doesn't need to call finance dept. by phone to know the open amount of a customer:  ERP gives her what she needs right on time.  As a result, work hours are used more efficiently and personnel do their job based on accurate and real-time information.  This means more accurate and efficient performance for your organisation.
  2. Business process based analysis of your organisation provided by ERP, helps you discover the bottlenecks faster and more accurate.  For example, a drop in sales does not always mean the sales staff are incompetent; it may be because of the delay in procurement which eventually leads to late delivery and customer unhappiness.  With ERP you look at your organisation from above as a collection of (usually) inter-connected business processes not as a handful of separate departments.
  3. Using best practices in every day business is a key factor to your organisation success!  Now, thanks to ERP you can simply adopt the most efficient strategies taken from sucessful companies.  For example if you are the manager of an automotive business firm, you can enjoy the best practices applied by Mercedes Benz and that is a 100% win -unless you're the Benz's manager herslef :-)
Conclusion
ERP is an information system which is integrated, business process oriented and based on best practices and its main audience/beneficiaries are top-level managers. Successful use of ERP makes your organisation operate faster and more accurate and considerably improves your understanding of the performance of  your organisation.  ERP makes space for you to do your job: making decisions.

Apr 12, 2011

Persian Utils

I'll do this in a telegraphic manner since it's too late and my eyes are burning with sleep.

I've created a repository on GitHub named persianutils.  The goal is to put the solution to the Persian locale specific problems I encounter out there so it might help others from searching the net for hours.

Currently there's a module calendar.py which implements date conversion from Persian to Gregorian calendar and vice versa.