Archive for category SDLC

Program to an interface , not an implementation

I have been lately discussing SOLID in my previous posts – some of the basic principles of OOD . Recently while doing my project work , we had to decide between Entity Framework  or NHibernate which are popular ORM layers in .Net framework .  The decision was not easy , we got stuck at Second Level caching support …and could not reach any decision right away. I started thinking that may be for now we have to write our layer in such a way that we choose one ORM , and then we can switch to a different one worst case if need be. Ideally a situation like this should not arise , but if it does happen , you need to be able to do it.  Once again I felt how a very fundamental OOD principle could come in handy –

Program to an interface , not an implementation.

These words above can be very ambiguous and abstract when you just read them .

However when seen from a context , you understand how powerful this is , and how it can increase flexibility and ability to switch . Seen from my own situation where we needed the flexibility to switch data access mechanism if need be, let’s understand this by constructing a scenario. For example , a common problem could be implementing a subscription mechanism for a data service that your system may provide. Users can subscribe to the data service and get notified when a change occurs. We need to persist the subscription information to the database , where you will need to use some database access mechanism.

As usual there is a presentation layer that gathers some subscription information and passes it along to the data service which persists the information to the database . For simplicity’s sake , let’s say we have a SubscriptionService , which is our data service for persisting subscriptions . We can discuss this further in the context of an ASP.Net MVC application – where a View is our Presentation layer through which Subscription details are collected. A controller action method is typically invoked to pass along the information to the server.

We can assume for our article purposes that our application provides notifications on Food Recalls. So the member user to our website subscribes to recalls for a certain type of food issued by different organizations like FDA etc. The Subscription in simplicity could be :

Please note : all code is pseudo only , this is not a working solution that can be downloaded and built.

public class RecallsSubscriptionService
{
    Boolean Subscribe( int userId, string food_type, string organization)
    {
           // data access code to insert subscriptions
           return false; 
    }         
}

Most of the times the controller action method would look something like this:

public class SubscriptionController : Controller
{
        [HttpPost]
        public ActionResult Subscribe(int userId, string food_type, string organization)
        {
            try
            {
                 SubscriptionService myservice = new SubscriptionService();
                 myservice.Subscribe(userId, food_type, organization);

                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }
}

So , we make a decision we will use Entity Framework 6 to implement our data access to store subscription information. The above code will work fine . The code goes into production . However later we decide that due to certain project requirements we have to switch to NHibernate. This is a tough situation – our controller here , who is a client of the SubscriptionService , is heavily dependent on instantiating this specific service which accesses the database with Entity Framework 6. Although we expected the problem could arise we didn’t design our system for this flexibility. Even though we encapsulated the data access code into a Service , we did not free the client from the implementation of data access because the client program is indirectly tied to EF implementation.

We need to make some changes , so our controller is independent of the future changes that could happen to the database access mechanism. To bring transparency into how data access may happen from a client’s perspective we need to introduce interfaces. We write an interface instead for the SubscriptionService :

interface IRecallsSubscriptionService
{
   Boolean Subcribe(int userId, string food_type, string organization);       
}

We could write two implementations of the above interface or we could just use the same implementation we had earlier , and replace it with NHibernate.

public class RecallsSubscriptionServiceEF
{
       Boolean Subscribe(int userId, string food_type, string organization) 
       { 
                //   implement using EF ;
                return false;
       }         
}

public class RecallsSubscriptionServiceNH
{
       Boolean Subscribe(int userId, string food_type, string organization) 
       {
              //implement using NH ;
              return false;
       }         
}
/*( not that the above approach is recommended , where you keep 
two implementations available for the same requirement. 
This is for understanding purposes only )*/

The above mechanism allows us to drive the Subscribe method call through the IRecallsSubscriptionService interface. In order to effectively use the method above , we will need to pass IRecallsSubscriptionService as a parameter to the controller constructor and use dependency injection in this scenario to have the right concrete class to be instantiated during run-time. I will not dive deeper into that because it is outside of the scope of this topic.

This is the whole basis of Dependency Inversion and Injection ( this is also the ‘D’ in SOLID ): here we program to an interface , not an implementation as we saw above. This gave us the flexibility to change our implementation completely without changing the client code. So the basic idea is programming to an interface decouples the client from the internal implementation freeing calling programs from knowing the internals leading to flexibility in changing implementation as the need arises.

Even in scenarios where there are published APIs , when you use objects  go up in hierarchy to program to the interface as opposed to the concrete class. So if you are using a List object and comparing individual strings-  then if this object implements IComparer , then program to IComparer –

instead of writing:

List myList = new List();
myList.Compare( myList[0] , myList[1]);

//Write as :

IComparer myList = new List();
myList.Compare( myList[0], myList[1] );

//This gives you the freedom to use a different flavor of Compare method if you need to ,

IComparer myList = new Array();
myList.Compare( myList[0], myList[1] );

The advantage of the above is ability to switch different comparison methods if they are available. And also test program can easily switch different implementations and see what works the best.

We also need to understand that “Program to an interface” should not be taken literally . Even Abstract classes can act as interfaces in this context and give us the same flexibility.

Interfaces should be used wisely and only when needed. If there is no potential for an implementation to ever change there is no need to bother with interfaces. For example , a Utility class that converts a string to a number. There is no need to write interface to this . Interfaces should also be used in projects where testability is a big concern and mocking may be required.

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SOLID conclusions with ISP and DIP

In my last post we went over LSP ( Liskov Substitution principle ) , how it helps achieve Subtype Polymorphism. We learnt how to think in terms of client programs and how client’s call to  programs can influence the quality and design of applications. The SRP and OCP are foundational principles on which LSP and the next one we discuss today , ISP manifest themselves.  It is not enough if Single Responsibility and Open Closed are understood – the rest of the three principles are where you see their applications and extensions. LSP , ISP and DIP all three teach us how to design from a client’s point of view. Uncle Bob calls it as “Clients exerting forces “  . 

The interface-segregation principle (ISP) states that no client should be forced to depend on methods it does not use

ISP helps formulate mechanisms on how interfaces should be segregated so the same interface can be useful to different clients. It’s a very powerful thought that can bring strong results. Single Responsibility talks about writing interfaces that have very cohesive functions . ISP takes it one step further and gives concrete ideas that give rise to reusable interfaces . This is where the relationship and the difference between SRP and ISP exists .

So how does ‘Segregating’ Interfaces help the clients ? Interfaces are meant to represent a certain type of behavior to the client and by virtue of their contractual representation promote pluggability. So when interfaces represent more than one type of behavior , they provide more than what a client needs . This leads to the interface becoming incapable of being used for plug-in purposes. Also they become ‘Fat’ in nature , with unncessary behavious not useful in the client’s context. Basically this is solidifying more on the SRP and OCP and stressing a whole lot more on how interface contracts should represent one type of behavior. Almost all patterns have a basis in SRP , OCP and ISP. Let’s say we are writing a class to represent a Persistence Medium. One of the most popular persistence medium is Database . So is XML . And a lot of applications use simple JSON files to store simple content.  Say , we start out by writing a PersistenceMedium class. So a simpe IPersistenceMedium looks like this :

Code is pseudo only , to describe the principle , not a working , compiled example :

// IResult is an imaginary interface 

interface IPersistenceMedium
{
       string fileName { get; set; }
       string connectionString { get; set; }

       void Open();       
       void IResult ExecuteQuery(string query);
       void IResult ReadFile();
       void Close();
}

//So our database class can be written like this:

public class Database : IPersistenceMedium
{
    private string _connectionString;

    public string connectionString
    {   get{ return _connectionString; }  
        set{ _connectionString = value; }    
    }

    public void Open(){  /* database open connection code */ }
    public IResult ExecuteQuery( string query );
    public void Close(){  /* database close connection code */ }
}

// The JSONStore can be written like this :

public class JSONStore : IPersistenceMedium
{
     private string _fileName;

     public string fileName
     {   get{ return _fileName; }  
         set{ _fileName = value; }    
     }

      public void Open(){  /* open a JSON file code */}
      public IResult ReadFile();
      public void Close(){  /* close file code  */}
}

See what happened above ? The Database class could not use ReadFile() and fileName and JSONStore could not use ExecuteQuery() and connectionString . Although both are variants of a PersistenceMedium behaviour , they are unnecessarily clubbed together from the perspective of Database and JSONStore classes which are the clients of IPersistenceMedium.

A Better way would be :

interface IFileConnection 
{ 
     string fileName { get; set; }
     void Open();
     void Close();
}

interface IDatabaseConnection 
{   
      string connectionString {  get ; set; }   
      void Open();
      void Close();
}

interface IDBOperation
{
     IResult ExcecuteQuery();
}

interface IFileOperation
{
      IResult ReadFile();
}

Now this provides interfaces that can be specifically used for Database or JSONStore because we segregated them keeping in mind different clients / client groups. The interfaces which can be used for JSONStore can be used for XML or any other type of file store. Similarly the interfaces that got written for Database can be used for any type of database , SQL , Oracle or NoSQL . The interface is less fat , with interfaces ‘Segregated’ strictly based on different client usages . This is SRP in effect, by using ISP.  What are the different ways of using these with the Clients ? One obvious way is multiple inheritance.

public class JSONStore : IFileConnection , IFileOperation
{
    private string _fileName;
    public string fileName
    {   get{ return _fileName; }  
        set{ _fileName = value; }    
    }

    public void Open(){ /* open file*/ }
    public IResult ReadFile(){ /* Read File */}
    public void Close() { /* Close File */ }

}

public class Database : IDatabaseConnection , IDatabaseOperation
{
    private string _connectionString;
    public string connectionString
    {   get{ return _connectionString; }  
        set{ _connectionString = value; }    
    }

    public void  Open() { /* Open Connection */}
    public IResult ExecuteQuery(){  /* execute query to obtain results */}
    public void Close(){ /* Close Connection */}

}

The above JSONStore could be very well be written as FileStore , in that case different FileStores can be used and IResult representing different result types form different types of files.

There are different ways to implement the above without multiple inheritance. One way is to use something like a Strategy pattern where IFileOperation has concrete classes for JsonFileOperation and XmlFileOperation – because each may have subtle read differences. XML requires special parsing and JSON is more of a string representation.

We have been able to establish in many different ways the value of SOLID – how it  leads to good design practices and understanding of patterns.

I will conclude without diving into Dependency Inversion – there are fantastic blogs including Uncle Bob’s report. Dependency Inversion distinguishes itself by establishing how layers should interact  without depending on each other. Again a powerful concept that has led to great programming practices including Test Driven Development and several patterns that facilitate the principle. SOLID is definitely worth your time !

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Finding the way to Design Patterns : more SOLID

So continuing into the process of finding our way into design patterns from my last post , we will try and unfold SOLID a bit more. Some of the SOLID principle interpretations and applications can be very subjective and a matter of debate. How do you know the classes that you wrote have adhered to the Single Responsibility Principle ? Is there a way to determine ? What does Single Responsibility exactly mean?  How far do you try and take these things…blah ..blah.

There needs to be a balance in everything of course.One needs to find a mid way between over-engineering and under-engineering. We need to create small classes with very few cohesive/related functions without getting carried away by having so many classes that we cannot manage those either. At the same time , understanding exactly how to create classes with just one relevant behavior or few cohesive functions can get tricky. It’s important to ask the question while writing a class , what is it that will potentially change in this class later , that can be re-factored into a separate class , so minimal changes / or no changes need to be made to the existing implementation when the change needs to be made.

It’s important to ask the question while writing a class , what is it that will potentially change in this class later , that can be re-factored into a separate class , so minimal changes / or no changes need to be made to the existing implementation when the change needs to be made.

If we take the Logging example that we discussed in the previous post , we discussed three functions a logger can do. Initializing a medium to log , Formatting to the medium itself  and Writing to the medium . So, they all look like related functions don’t they ? So they all can go in one class , which is a violation of SRP . If we take one step further into re-factoring  perhaps it’s easy to recognize right away that there are different mediums to log , each requires a different method to write to itself. So we create separate classes for the medium . Yes , we applied SRP here.

What about formatting ?  Can formatting change ? Yes, it can . Say we need to add a new logging medium called Mobile Device. To the mobile device , you want to send text messages whenever severe conditions occur. Doesn’t the format of what goes into a database differ from a mobile device ?  Also , later down the line the potential users of our Logger may require that they want the format of the message a little different. Now if we did not separate the format function into it’s own class , we have it as part of the class that writes to the medium or worse as part of the Logger class. Logger class is actually our client facing class that the client would use to log messages . Just to change  formatting , we have to go and change this Logger class or the medium classes.

At this point we need to consider  whether it’s worth writing something like this:


   1:  interface IFormatter {
   2:   
   3:  public string Format( string message );
   4:   
   5:  }
   6:

and the logger could do something like this :


   1:  public class Logger{
   2:   
   3:  public Write( IFormatter formatter){}
   4:   
   5:  }
   6:

Or let’s go couple of steps further along these lines,


   1:  public interface ILogMedium{
   2:   
   3:  void Write(String Message);
   4:   
   5:  }
   6:

   1:  public class LogToDatabase : ILogMedium{
   2:   
   3:  public void Write(string message){
   4:   
   5:  // medium specific logging
   6:   
   7:  }
   8:   
   9:  }
  10:

   1:  public class Logger{
   2:   
   3:  ILogMedium _logTodb;
   4:   
   5:  IFormatter _formatter;
   6:   
   7:  public void Logger( ILogMedium logToMedium,  IFormatter formatter )
   8:   
   9:  {
  10:   
  11:  _logTodb = DBMediumProvider.Create(); // DBMediumProvider could be a creation class
  12:   
  13:  _formatter = DBFormatProvider.Create(); // DBFormatProvider could be a creation class
  14:   
  15:  }
  16:   
  17:  public Write(String message){
  18:   
  19:  _logTodb.Write( _formatter.Format(message) );
  20:   
  21:  }
  22:   
  23:  }
  24:

Please note : The code above is not a working solution. It is only like pseudo code to demonstrate the thought process .

The advantage of the above is we kept the formatter completely separate from the medium , as well as the Logger class. This allows us to plug in new mediums , formatters and configure them based on our needs. Also , if there are bugs it’s easier to fix a specific class as opposed to one big class which could potentially break other functions.

This brings us to the Open Closed principle , which is the next one and the ‘O’ in SOLID as we all know.

A consistent use of SRP can lead to OCP , which simply states: A class should be open for extension but closed for changes. This does not mean that classes should be completely sealed for change , it means that the class should be in a state where only bug fixes should be made and new functions should be added via new classes , minimizing implementation changes to the existing classes.

Words should not be taken literally here : once you wrote the class does not mean that it cannot be changed at all : however we should get to a point that , when behavior changes in predictable ways, you should not have to make several changes into a single class or several classes in the system. An ideal situation would be where you achieve the change by adding new class / code rather than changing existing code . For anyone who has been in programming for a few years supporting production systems , this will make a lot of logical sense.

Whatever we discussed above with Logger example with reference to SRP will apply to OCP as well , because OCP can be achieved by applying SRP consistently. So had we written the formatting in the Logger or the individual medium classes we would not be able to add new formatters or change existing formatting without changing the Logger or the mediums classes , plus mix and match formatting with mediums . The way we achieved OCP with Logger example is we gave the Logger a Single Responsibility of writing to the medium. We gave the Medium classes a Single Responsibility of initializing / creating the medium and specifically write to that medium as well. And then OCP came into effect when we made it possible for new formatters to be added to the system by simply implementing the interface IFormatter and adding that class to the system as a plugin. So , when a user wants to use the new Formatter , she can do it through the configuration system and that formatter will get automatically used which needs to be implemented through some creation classes of course , which is a separate topic – an example is Factory Method pattern.

Several design patterns use the SRP and OCP , and following the above two will put you in the mode of clean and efficient code . Some popular patterns like Strategy , Factory are all based on OCP . We will continue with this discussion in the next post , happy programming !

Few references :

Wikipedia definition Open-Closed

Interesting read on OCP by Jon Skeet

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Finding the way to Design Patterns : SOLID

In my previous post on design patterns I discussed about why it’s a challenge for developers / organizations to adopt patterns as part of their development practices. I also had suggested that a dedicated effort to re-factor code should be made continuously as part of software life cycle especially in the early to mid-stages of development. Having said that, how do you go about re-factoring? How do some of the object oriented principles and design patterns help with re-factoring? So, if re factoring is important, the object oriented mechanisms that allow and facilitate this are important as well. In conclusion the learning needs to happen, slowly and steadily – as a result it will start becoming a habit to incorporate some of these patterns related principles.

I guess the challenge is where do you begin? There is a ton of information on the web, it’s all too overwhelming, scattered and fragmented. You need a have a structure and if you just pick up the Gang of Four book (our bible for design patterns), it can seem rather academic and intimidating for the first timer, abstract as well. The book of course is great, however it’s hard to jump into patterns pragmatically just by reading it.

As in my previous post in my concluding paragraph I had said that getting familiar with SOLID principles developed by Robert. C. Martin is great way to get started with principles that will lead the way towards patterns programming later.  Before expanding upon technically on what SOLID is about, I would like to discuss its importance in the whole OO programming space. If you come from a OO language background like Java, C++, C# etc. you already are familiar with Encapsulation, Inheritance, Polymorphism as foundational principles of OO and they are a daily part of your programming life. SOLID takes it one step further, lays out 5 principles that you can apply to re-factor and improve the code making it maintainable, reusable and efficient.

So when you start applying SOLID, you basically are applying some of the fundamental principles on which Design Patterns are developed. SOLID stands for Single Responsibility, Open-Closed principle, Lishkov Substitution principle, Interface Segregation and Dependency Inversion.

If you just take the first two: Single Responsibility and Open-Closed principle, just there you will improve the structure and quality of your classes.

Single Responsibility states: a class should have only a single responsibility.

Say, you are writing a Log class whose job is simply to write messages to different logging mediums. However you also gave it the responsibility of formatting the messages for these mediums, because it’s part of logging function. In addition, you gave it the responsibility of initializing and choosing the medium to log into, for ex: Event logs, Database, Log files etc. So now the Logger class has multiple reasons to change – one is, Write to the log medium, another is formatting the message: perhaps different mediums require different formatting and on top of that initializing the medium . So your class has now grown into one giant monolithic program that has multiple reasons to change – formatting for each medium, initializing the medium and logging to the medium. So if you need to change only one aspect : say change the formatting messages in database , you have to change that class and the rest of the code could possibly break because you needed to make changes for one aspect. We come across situations like this all the time in production code where we change one thing and potentially something else breaks , without us intending it . This sort of programming makes the code not only fragile, but totally un-pluggable.

Ideally in this situation, the Logger class should just take on the responsibility of writing to the medium being free of what medium it is writing to and what formatting that particular medium needs. Although it seems like they are all related functions , they merit to become individual classes based on their specific function and behavior. More so, ideally you should write an interface that can be implemented to write to different log mediums.

public interface ILog
{
void Write(String Message);
}

As you see , when you just take this one principle and follow it while writing the code you will see that you have written classes that are light weight and each is meant to do one particular job – this makes the design pluggable , reusable and efficient  . You can create classes that are specific to a medium – so adding mediums for logging becomes easy later. Also if there is a change required in it , say how you format the message for that medium, you change only the corresponding medium or the formatting class, avoiding the risk of the rest of the code breaking due to the one change you made in one big class.

As you go further and start applying one by one each principle you will see that certain patterns are shaping up, and possibly they can be applied to common scenarios. I guess I will stop here for now, and conclude that the first step is definitely to understand SOLID and start applying it in your programming life seriously.

Below is a great Video on Single Responsibility Principle by Robert C. Martin himself to learn more on it and get started :

We will discuss more on the rest of the SOLID in the upcoming post …until then happy programming.

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Technical Knowledge : Breadth and Depth

I could have titled this blog “Professional Knowledge : Breadth and Depth “ – however thought that since my blog focuses on a niche readership,  “Technical Knowledge” would sound more appropriate . Anyway, often times at work discussions come up on how mastering a certain subject area leads to growth , especially for technology professionals. Depth plays a key role in technology professions in leading to both job satisfaction and growth. So is depth more important that breadth? I think both are equally important, and they both contribute to an individual’s job performance and satisfaction.

Why Depth?

1) Depth in a subject area establishes you as an expert – the deeper you drill within a subject area focusing on niche fields the better you will do at the design and execution level. Depth is instrumental in achieving high quality results, thus better performance by you as a professional. Say for example , you develop a mastery on ‘Design Patterns’  with regular practice and study – your expertise in that area could play a pivotal role in robust architecture and solid implementation of the architecture which will take the project a long way for years to come.

2) All technical projects / undertakings are team efforts – not individual heroic endeavors. An ‘expert’ in each area of the technical solution will be required to fill the places as opposed to some one who just knows a little bit of all. For example , a software project may have a ‘Single Sign On’ expert just handling the Authentication aspect of the solution where he/she is the ultimate ‘go to’ person  for it. Hence having a niche expertise helps you build your value within  the organization almost always to fill in that spot of your expertise across different projects. A key to job security especially for those who work as consultants.

3) Depth can easily make you a ‘Mentor’ or ‘Leader’ in your area , very important for your own job satisfaction . Let me give you my own example in this case. All along in my career , I made careful choices while consulting – I chose to take up projects which were ‘ASP.Net and C# ‘ centric – this quickly helped me establish myself as a mentor as well as a lead in those areas allowing me to provide expert help and guidance across projects. This leads to great satisfaction , sense of value and achievement.

“Having a niche expertise helps you build your value within  the organization almost always to fill in that spot of your expertise across different projects.”

Why Breadth ?

1) Breadth gives you a vision , an ability to see beyond the purview of a narrow expertise. For example, a business problem can be solved either with a Client Server Architecture or Service Oriented Architecture. If you do not keep up at least with what SOA means , it’s application at a high level , your problem solving abilities are stunted by lack of broader knowledge.

2) If depth establishes you as an expert , breadth can establish you as a sound thinker. A ‘subject matter expert’ may not necessarily be able to lead the overall project , whereas breadth

sound thinker

helps in being a leader and decision maker for the whole project. A typical software project has BAs, QA , Developers, Designers , Project Managers etc. – a professional with a broad understanding of how each works can listen and guide everyone effectively .

3) Breadth just makes you a lot better communicator – it’s easy to communicate in areas where you are deep , however breadth enhances the conversation power many fold because you can quote examples from beyond your forte. A great asset for meetings , hallway brainstorms and white board discussions. This can lead you to opportunities that you want to explore to grow as a professional.

 “Breadth gives you a vision , an ability to see beyond the purview of a narrow expertise.”

The power of knowledge is immense in IT : having both depth and breadth will round you up as a sound professional as well as a leader. Practice gives depth and study can give breadth , combined the result is a highly valued professional.  I always feel in technology you can ‘Read your way up’ –  a small investment in time of may be even an hour a day makes a big difference , it keeps you abreast with the new stuff.  I think if one has the time , if say you work 9 hours day , may be extending it to 10 hours by adding that extra reading time at work itself will better prepare you with your project work in applying and understanding better techniques.

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Continuous Integration : the Value Proposition

The topic of Continuous Integration  has gained a lot of ground in the past few years in the Software Development world – several high quality tools have emerged . Some companies have adopted it as integral part of SDLC methodology. Some I think are still trying to understand it , however a lot have not yet just made it their daily practice due to either lack of tools within the company or lack of a process. I have worked in this industry for more than 20 years and there are several reasons why I think CI adds immense value to software development process to make it efficient and productive. After going through many sucessful and some unsuccessful projects , here is how I conclude CI brings in value:

1 ) Bugs are detected on a daily / regular basis and remedied right away by integrating code checked in by different developers into Source Control . Continuous Integration works by kicking off a build process on your build server based on check-ins made by the team . CI tools give you the option to build as a check-in is made or at a certain frequency or at a certain time etc. So you get to control how you go about it. If a Build is required to be done as a check-in is done by a developer , right away bugs / integration problems get detected – they are remedied as you go along daily, reducing many integration hassles and mitigating risks earlier.

2) In medium to large scale projects there are different groups , stake holders . DBAs who work in conjunction with Application Developers sometimes want to look at GUI or application in action to see what type of data was entered that caused a SQL / Stored Procedure to fail. Although DBAs don’t necessarily need to look at application running in Dev Integration server to detect data related problems , however it gives them a great way to Visualize what an application developer has to say about why a SQL exception may have occured. It expedites problem detection by running the application as well as other runtime SQL method call capture tools like SQL Profiler concurrently.

3) A little while ago I wrote a blog about how the gap between UX Designers and Developers can be bridged by following certain practices with the development cycle. Continuous Integration can play a key role in shortening the gap : UX Designers often or almost always need to see the final integrated UI after the UI developers take UX designer’s Mocks / CSS / Javascript and integtrate their code with it. If you have a CI in place the UX designer can just go to the dev server and look at the latest dev build helping him see how the final UI looks without having to sit next to the developer. Obvious as it is , this will aid in UI layout related debugging and early detection of any cosmetic problems as well as work flow related issues.

4) Progress Track and Control are an integral part of Project Management and SDLC. PMs , BAs and Management stake holders need to be kept in the loop as regularly as possible for better Control management of any software project. A great way to measure development progress by non technical groups is to look at the actual application taking shape on the Dev Build server. Needless to say how this will help very early in the Iteration of a project. Any problems , risks or change requirements can be made early on saving time and money which are the two crucial cornerstones for a Project’s success.

5) In this age of globalization and distributed enterprise , CI can play a crucial role in bringing different groups together . Developers could be in India , UX team could be in US and other stake holders could be anywhere. If dev build servers can be accessed via the company Intranet or VPN from anywhere then the communication and collaboration gap is not widened by geographical distances and Project can be delivered on time even with a distributed arrangement like this. Here is a diagram that visually conveys the idea….

Continuous Integration Integration with Project Team

Entire Team Interaction with CI

The reasons above qualify enough for every organization to adopt and invest in CI – especially for medium to large projects . There are several tools available – form Open Source to Proprietory . Cruise Control is a well know open source tool as welll as TFS by Microsoft which ia an end-to-end SDLC tool. These are just examples. Web is full of articles, blogs and tools that you can use for CI. If you have not taken the time to integrate it into your team’s dev process , wait no more it’s worth your while and money.

Cruise Control

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UX Designers and Developers: Bridging the gap

The other day I was watching a presentation on SlideShare about how the UX designers can work with Developers without getting into conflicts. All my career like many Software Engineers I have had to interact closely with UX designers …the problem mostly stems from the fact that the tools used by both the groups are different as well as the frameworks and languages to achieve the end result . There is some overlap between the two with Javascript / JQuery – however, depending on whether the Client Script impacts the UX interaction or some server related activity , the designer or the developer takes over the definition of the code. A synergy needs to be created between both of them because at the end of the day the UI that we see is the combined effort of these two groups.

The tools and frameworks themselves don’t offer much in terms of creating that collaboration and synergy – however as part of the process , the groups need to mingle and work side by side. Designers do need to understand how the developers incorporate their code into the designs- and developers need to understand to a certain extent the working of Styles and HTML .

Just recently I went through two ASP.Net MVC projects and we used the help of a UX team to put together our styles and layouts. As usual, the mock ups were created which the developers used to incorporate their code into, to achieve the end user requirement of the UI.   There were issues with how the developers had used the mock ups with their code , as expected. Most times the designer would call me and say hey I need to be able to run the web page in development like the developers do, so when I make a change I see it and go through iterations. I made a decision that she needs to get familiar with running the solution in Visual Studio 2010. This helped a lot – saved us precious time by the designer not having to ask the developers to make a fix and publish it on the dev server. The designer at the same time was happy having the independence to make the change in the final UI and seeing the page in debug mode.

One of the other bad practices I noticed with a recent client is that the UX designers would put their wire frames either in Dropbox or zip them up and email the development team. The development team had to always download them and copy one by one in their project. There was no version history , no way to tell what changed other than looking at the rendered page . This can become a development nightmare in a very UI centric project.

All mock ups and styles should be version controlled , preferably in a similar version control system as being used by Developers. This makes it easy for Developers to compare the changes as well as Share the styles if it makes sense into their project from the styles folder of the Designer team in Source control .

I am not sure in the future how much will be offered by Development tool makers in terms of both Developers and Designers being able to use the same tool to do their jobs. However I think if Designers and Developers both understand to a certain extent each other’s code , work side by side and follow good version control practices,  the UI development would be much less of a hassle. The Designers need to understand the interweaving of Server side code with Client side code and the Developers need to understand Javascript , CSS and HTML standards to a reasonable extent.

So there need not be any love lost between Designers and Developers – collaboration and communication can surely bridge the gap.

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