Walter Almeida's Blog

Introducing my favorite ORM tool: Llblgen

In a previous post I introduced the concept of ORM tools and their high importance in software development projects. Today I want to talk quickly about my favourite ORM tool: LlblgenPro, and explain why it has been one of the best tool I have had the chance to use for quite a long time.

 

Have you ever been really amazed by reading the marketing material for a product and think: hey this is what I need! Looks like it's doing everything I want/need plus even more things I would not have thought of first, let's get it!

You would then go and download the trial, with the grand hope that you will be simply satisfied, and not once more disappointed by an advertising façade, selling why the product is the best of the world.

So here you are, trial downloaded, and first eliminatory test is how easy or hard the product is to install and first use. Once the first, supposed easy test is pass, then you start using the product. If you are lucky, the first tries are satisfactory and you still find the product very attractive and are ready to go and celebrate this with your friends. If you are really that lucky and don't live in the real world, you never discover any problem with your newly purchase product and live happily ever after.

However sad but true, more common scenario is that you discover one by one, sooner or later, the flaws and problems and bugs that goes with the product. And interestingly or not, this was not sold on the advert. But the thing is that it comes in a bundle: you get the great stuff and the bugs and problems all in one for the same price, how great is that?!

Unfortunately this happens quite a lot, it is very common to have to make compromises and use a tool because it has great features and you need it, accepting all the bugs, design and functional flaws, perhaps lack of flexibility that come with it. Well you still can contact this great support team: they say that they are available to solve your problems, so wanna call them? Ok right: one doesn't loose anything to try, except perhaps patience and hair…

Ok all is not so bad. You have products to absolutely avoid, and products that are better and being a pleasure to use despite of some drawbacks. And you have few tools that are absolutely phenomenal, and Llblgen Pro is IMHO one of these.

I have already used Llblgen Pro on several big size projects for several of my clients. For information I am always using the adapter flavour of the templates and runtime as I am working on large distributed tiered-architectures and need the disconnected pattern for communicating between tiers, throw web services.

So I must say I keep enjoying the fact that I really love this product, and cannot find anything significant to complain about, which is very uncommon. And Frans, where are the bugs? Pretty very well hidden I must say, was looking for them but apparently didn't get any luck: I find the generated code and runtime extremely stable and robust.

Ok what else can I say? Well, installing the product is very easy and nothing to report, using the designer is pretty straightforward too, and using the generated code made very easy too: the generated projects are including all the proper references, are compiling perfectly fine, and you then just need to reference the generated project and runtime support libraries to be ready to map to your relational data in a full object oriented way.

Even more important: re-generating your projects after changes to the database, on existing entities or creating new one is extremely stable and pain-free too. May you add items to your projects, add your custom code, all is re-generated taking very good care of the work you have done before.

Ok you will tell me that changing the database has impacts on all your code, not just you data access and business entities layers. Well, ok, but don't forget we live in a full strongly typed object oriented code now. So may you have broken your code after update of the database and regeneration of the business entities layer, well, you will know it at compilation time and fix it very quickly!

Another very important point for me is the quality of the generated code and of the runtime source code. For such a technical tool one expect very high quality of the code base, and you get it with Lllblgen. When using the generated code or runtime libraries, you never get the impression of a poor design or dirty kind of object oriented, having design inconsistency or suspicious quality issues. No, this is only great clean object oriented code, handsomely designed, I just LOVE IT

What else can I say? Well the development efforts are pretty well sustain in that Llblgen Pro keeps constantly up to date with the newest versions of Microsoft .NET framework when they get shipped. And much better than this I must say: Llblgen Pro really makes the most of new features of the .NET Framework very fast. Example is the very early support of Link (though Link to Llblgen) and Dynamic Data.

Another point is the extra features that are provided out of the box for you, for free. Examples are support for auditing, and security (authorizations). So you have access to points of extensibility for your application just by using the tool. Let's see what new exciting features we get in the future.

What else? Oh yes, support. Llblgen Pro has got the most amazing support service through its forums. You get answers extremely fast to your problems and issues and bug fixes integrated quite fast in subsequent releases. And it is working, they really are there to help you, it is not only sugar to make you buy the product!

I see one bad thing though about the tool…. And it is its name!! Just still haven't really managed to adopt it J Well who cares would you tell me?

Just one thing to be aware of: I am telling a lot of great thing about Llblgen Pro, just be aware that you will have to go through a learning curve before smoothly master the framework. However it is the same with any framework and believe me: it really is worth it. And with the addition of Link to Llblgen, developers knowing Link will have their opportunity to leverage their knowledge and shorten the time needed to master the tool.

Ok enough for now, you can just go to their website to get more information on the tool. And I will write more posts on scenarios in which I am using Llblgen Pro. So go, and try it! And NO, I don't have any shares on the product, just like to tell when there is a tool that deserve attention. And I will dedicate a section in this blog, dedicated to registering interesting and useful tools and framework, as it is one part of the whole "Building Business Oriented Software Solutions" concept.

You can also read my post about Object Relational Mapping (ORM) overview

I have a Dream, an Ambition, a Destination and Faith

I tried today to search for myself on the cloud, trying to "google" keywords and hey! I can find myself, much better than a week ago! I realized that I start to gain visibility, yet not having many visits, but surely getting more and more visible globally. And I must say it is a great satisfaction and I realized something is happening, that the seeds I had been throwing for so long are growing now. And this is why I felt like writing today's post, as a summary of the evolution of my thoughts and feeling during the last many years.

   

I had a Dream….

I had a dream, a dream of a harmonious life, a harmonious world. A world where you get what you truly deserve, where you safely and openly receive and give equally to your surroundings. And I had the even more beautiful dream that this harmonious and positive environment could be complete and extend through personal, professional and social life; and that the business world could seamlessly be part of the host environment for such good and true things.

I had the dream that profitable business and success can be achieved with respect of humanity, justice and be achieved in a positive, loyal and genuine collaboration with the surrounding world. I had the dream that a business can be not only driven by return on investment but also be based on deeper principles, with the aim to achieve a higher goal, born from the mind of the creators and shared by the whole company as the driving force.

   

I experienced Deception…

I experienced deception; saw dark sides of the real world, witnessing conflicts of power, worth: been part of some, seeing corruption, understanding the sadness and negativity of extreme individualism, ignorance of others, disengagement of good principles for the sake of un-deserved, dirty success.  

I experienced deception, for having given 200% of myself for companies that did not deserve so much, at least not so much from me as I was wrong in my beliefs of what they really were. 

I started to give up and felt forced to slowly engrave in my soul this so often heard hurting sentences: "That's life, there is nothing you can do about it, you should stop dreaming, you should be adult and accept reality and live in the real world…"

Resignation was eating me from inside, driving me sad and empty. However there was still this little spark of hope in the depth of my heart, this great positive energy but made miniscule by the impact of experiencing life and uncontrolled interaction with the outer world. Sad but still dreaming from time to time, I woke up one day: HEY !! I AND ONLY I decide what my reality is, I decide if I want to keep dreaming, if I want to make my dreams my own reality!

    

I had an ambition…

I can say nothing but thank this little spark, my guardian angel to have always kept me alive, pushing me to fight, stand for my beliefs, for my dreams, despite of any negative signal that the dark sides of the outer world could send me. So "that's life? There's nothing I can do about it??"… No indeed there is nothing I can do to change the big size company I am working for, if I don't believe what they are doing is right. No Indeed I can't change my so called friends if I believe there are not worth it and don't follow the same principle as I do. But YES I definitively CAN stop complaining, stop being negative, and I CAN choose the company I am working for, I CAN choose my lover and my friends, and I CAN be proactive, and do whatever I am supposed to do to go for what I believe, I CAN choose my life.

My choice was to create my own company. I always have had my vision about how a business should be run, how I would like to build a trust and win-win relation with the members and partners of the company, what good principles should be applied. Yes I knew that I had not a business educational background and that very experienced business owners could just laugh at my words. But still I had my vision and my choice was to implement it, learn by doing and challenge my own beliefs. And I am very experienced myself in my own beliefs; ideas don't make it all, but work and courage just do the rest.

I had the ambition to create a company the way I imagined it, the ambition to prove to the others and first to myself that YES, I can dream and yes I can make my dreams my reality. I knew there was a path to achieve this journey: courage, faith and hard work. I also knew that the path would be long and difficult, but that it would be worth it, and that no big fulfillment can be achieved with no significant challenge and full dedication. 

   

I have a Dream, an Ambition, a Destination, and I have Faith!

Today I have a dream, an ambition, a destination and faith. I simply don't give importance to my deceptions apart from learning how to avoid them as much as possible and how to accept them when they happen to quickly let them fade out.

Today nobody will take me out of my path and my beliefs, a process has started and I have a destination: go for my beliefs and build a company the way I imagine it, the way I dream it. I want to build a company that is truly different, a company where every member will be part of the success, appreciated for his/her skills, courage, and personality. I want to do business a different way, driven by honesty, justice, merit and true human relationship, in the best shared interest of all participants, be they internal or external to the company. I want to go beyond regular business and build it with the same driving principles that I apply to my own personal life. This is my ambition, my destination, my life; faith, positivity and support of my loved ones will be my energy to do it.

Event based architecture and test driven development

I listened today an interesting podcast related to event based systems and one aspect especially caught my attention: how an event based architecture is a good cadidate for test driven development.

You can find this podcast on DotNetRocks: "Ted Faison takes events to the limit" and the speaker is Ted Faison.

So first interesting point is the difference Ted makes between events based architectures and event driven architectures. Ted describes event driven applications as applications that react to events and therefore whose inputs are events but events are not necessarily used as a core design element of the application. With no events fired, event driven applications are just idle. On the other hand event based applications are applications that are architected and designed with events as a core technique to inter-connect application components. Events in event based architectures are really a first class citizen, design element of the system.

An interesting point is that in a properly designed event based architecture, the inner components of a system are loosely coupled, and you can even imagine changing connexion between components, either statically through configuration, or dynamically at runtime. And high level loss coupling in software architecture is definitely a high goal to aim at.

To design an event based applications, and enforce the components lose coupling and ability to map and inter-connect components in a configurable way, well approved patterns exists to do that, so an event based applications will most probably integrate patterns like builders, binders and coordinators. For instance, to achieve the highest level of loose coupling, neither the receiver of the event nor the emitter of the event should know of each other; and to achieve that, a binder component would have the responsibility to wire and connect the components.

So here we come to the very interesting part of Ted's talk: event based architectures are by essence well suited to test driven applications due to the lose coupling aspect they promote: you can imagine testing single components of your applications without having to bring up the whole application including databases, web context and all expensive or difficult to test resources. And to not bring the whole application up, the only thing you have to do is to simply not connect the components; or to connect to mock up components instead for testing purposes.

And it is commonly understood and approved now that TDD development is a very good practice to build robust, maintainable and flexible systems, even though quite often proving to be a big challenge. Go event based and you have a good starting point! I am personally using dependency injection patterns to build the loose coupled application architectures + dynamic mocking framework for test driven development (more on this on other posts). Event based architecture is another interesting strategy to achieve the same, while having its own advantages and draw-backs. So up to you to decide on one, or maybe any other alternative!

So as a conclusion, I must say that Ted Faison's podcast was very compelling and convincing and an enjoyable listening session, presenting a deep look on amazing possibilities open by using events! It could worth having a look at Ted's book now: Events based programming: Taking events to the limit.

REST Versus Web Services

Okay, I had been hearing a lot about REST lately, not really knowing what it was. Seemed like standard web stuff for me, lots of talks about HTTP verbs, post and get and that kind of things. So I wonder was what was new in the whole idea? I therefore decided to educate myself a bit and started with listening to this podcast of Software Engineering Radio: Stephen Tilkov on REST

So indeed there is a lot about just standard, existing web standards in REST, and this is what somehow makes it powerful. The new idea is to use standard web techniques to perform inter-communications between systems, in a SOA fashion. I won't enter into technical details and explanation on how REST works, first of all because I am not an expert at all and secondly because there is already plenty of documentation out there on the cloud. I would advise you listen to the podcast for a start if you are completely new on the subject. And good thing about this podcast is that the speaker is coming from the web services world and moved later to REST, he therefore has a good idea of the differences and pro and cons of both techniques.

 

My intent in this post is to try to analyze what REST means, where it apparently fits in the web and SOA world and what may o may not the proper scenarios to use it. I will do that in a very humble way, dropping my first thoughts on the matter. I may be missing important points and be inaccurate on some others so all comments are very much welcomed!

 

At first REST appears like a simplification of web services, SOAP and WSDL technologies to remotely connect systems in a system implementation technology independent fashion; there is obviously a technology common point in it and that's happening at the transport and protocol level, but internal technology used to implement the communicating systems can be anything as long as it is providing REST end points. I remember when in the past I was using DCOM to connect systems, thinking that such component technologies like DCOM or CORBA where the proper way to make distributed systems communicate and the de-facto standard (or multiple-standards I must say as they are not technology agnostics). I remembered then when I first heard about web services and SOAP and thought: hey what's that!! we have great, complex technologies like DCOM or similar (by the way I Loved COM...) to interconnect systems, so how can a simple kind of loose coupled messaging system could possibly do the trick instead and efficiently connect my systems?? Well today in state of the art architectures, inter-applications communication is (in most cases) handled through web services, at least for communication outside of the company, or between systems that need to be kept independents and probably implemented with different technologies or by different teams. So will REST become the new standard the same way web services did in the past years?

My understanding of REST is that it's mainly useful for CRUD like operations, even though you can add support for more custom verbs than the standard HTTP verbs (but then you lose part of the advantage of seamless and full integration on the web that you would have by using only standard web and http technology). The main purpose of REST is to see business entities as web resources and access them the same way you would access a web page or an image or any other resource through HTTP. Great thing about the idea is that there is nothing new except! If you know how to get an Http resource through its URL, you know how to get a customer entity through REST, isn't that great? It means that interconnecting applications could prove dramatically easy. However if you need a "real" business service that does more than just CRUD operations, then you better off, IMHO, keeping working with classical web services, WSDL and SOAP over HTTP (or other transport layer BTW). To summarize, my understanding is that for enterprise level, business applications, classical Web Services could still in many cases remain the best choice. Another scenario is the need for advanced enterprise wide services like security, confidentiality, transaction (even though transactions on the web has to be taking with care, we should rather be talking of compensation systems), asynchronous processing, then classical services will have much more to provide with the WS* implementations.

Another point to note with REST is that the communication is quite "relaxed". There is no notion of strong data type as there is with WSDL contracts. Therefore it's up to the client to know about the data that is received. If you need extra expressivity for your service then REST might not be the best choice. Well one can argue than REST can get business entities in an XML format, so you can add expressivity through schemas. Other issues I can foresee: how do you handle versioning of your services with REST? How do handle service location and service directories? Well there are many aspects to cover and would require more writing (and more investigation!) and will not be covered in this quick overview.

On the other side, for web facing services, REST will be a great solution: after all, most of the mashup web scenarios are using CRUD operations, and not even CRUD operation but simple read operations in many cases. REST is then much easier to use to mash up services than going through web services which need proxies to be accessed, and specific knowledge of SOAP and WSDL. And for what security is concerned, forget about all WS* specification: just use standard web security protocols, making interconnecting systems on the web in a secured way much easier and accessible to more people.

Well that was just my basic vision after first a first go through REST talks here and there, let's see in the future what comes up!

Oh, another wonder I had: hey! we're having this new, exciting feature of Microsoft.NET framework called WCF and it is all about connecting systems in a (as far as possible...) technology, protocol and transport independent way. So what about REST versus WCF?? Well good news is that WCF now allows to expose services through REST and consume REST services, so this is just a great thing, because one can invest on WCF without having to wonder if REST and a REST implementation would be a better choice: no worries: it's part of WCF through the new WebHttpBinding! So let's see how easy it is to build a WCF service, expose it through SOAP and with simple configuration change, expose it through REST. Haven't tried yet but should be pretty straightforward! We can see with this specific case an example of how powerful and extensible is WCF!

 

While we are talking about Microsoft and Microsoft technologies, I guess that REST will be interesting for Microsoft in many scenarios, let's see what they do and if they use REST for interconnecting their various systems. For instance we can already see coming the generalization of the use of the Entity Framework and especially the EDM (Entity Data Model) aspect for interconnecting Microsoft systems and exchanging data (more on another post). So REST would be a way to exchange the EDM entities across systems like Astoria Data services, Velocity, SharePoint and much more… And I was telling that REST seemed a good candidate for CRUD operations; well velocity and Astoria are all about exchanging data in a CRUD fashion, aren´t they? So let´s see how all will be consolidated in the future!

That´s it for this first overview of REST versus Web Services.

Golden Rule #1 - Don't write code!

The software development golden rule number 1 is: don't write code. Well… seems quite inappropriate to say that about a software development project! The title is a bit exaggerated and the idea behind this golden rule is that you should code only what's mandatory and linked to your business and limit the lines of code to the minimum.

The less code you write, the less time you will spend in writing code (obvious), the fewer bugs you will write, the less code you will have to document, maintain and make evolve. And the less code you will have to refactor sooner or later. This refactoring aspect is quite important and will be the object of another rule stating that any good quality code or software architecture has to go through many refactoring cycles during its lifetime.    

So here are some advices to drive you to limit the code you will have to write:

1. Develop simple solutions. The simpler, the better (another golden rule BTW) and the less code is required. Obvious isn't it? However creating simple solutions IS a challenge. How many times have you been in the situation where you're asking yourself: hey that was obvious, how didn't I think about it in the first place? Thing is that as developers we have complex minds and are looking for the most amazing solutions, and it can become over killing and drives us to developing over-engineering solutions. Good practice is to always try to think twice on a solution and wonder if it could be made simpler. Do peer to peer code reviews with simplicity as one of the goal, presenting your work to others and having your solution challenged is a very good way to enhance and simplify your design

        

2. Linked to previous point is: always develop minimal solutions, answering a direct functional need. As passionate developers we often tend to do too much for the sake of building great applications. Yes you need to design and develop with evolutivity in mind, but wait for the functional requirements before make your design evolve and implementing more that necessary. In the mean time you can concentrate on building simpler, bug free applications and spend the remaining time to develop the unit testing code. And don't worry: new requirements will come and you will have the opportunity to express your creativity on something really required and useful, so be patient!

        

3. Reuse existing components (or frameworks) whenever possible and whenever they are not a company asset or directly linked to the business you are working for. There reusable components can open source components, third party out of the shelf components or your own components. One of the most obvious examples is the use of a GUI framework. You don't want to write a new grid component unless you have a very specific need or unless your business is to build GUI components. What you will have to care of though, is to make sure you choose stable, good quality and well supported components. So spend some time in selecting them and then reuse them in all projects where their use makes sense. Other obvious components to use are those which are related to technical, transverse concerns such as logging, dependency injection, data access and much more...

        

4. One layer of abstraction above components is the use of existing applications or server applications. For instance (almost) no-one will develop his own operating system, or relational database system. These are obvious examples, however an apparently not so obvious one is reporting and you can see companies developing their own reporting layer where one could leverage an existing reporting solution. In the Microsoft world this is Reporting Services, part of the SQL Server services. Another example of an out of the shelf application server is Microsoft SharePoint Server, full electronic document management, collaboration, publishing (and much more) application, fully integrated with the full Microsoft application suite, especially Microsoft Office. Of course there can be a licensing price to pay, but usually the benefit and return on investment is far beyond the licenses you will have to pay, providing that… you choose the right tool for your need! So same story than for components: you should carefully take time to evaluate and choose the right set of applications for your need! But when that's done the gain is then huge.

     

So as a developer you should focus more on evaluating and choosing components, frameworks and applications (unless you're working in a big team and have an architecture group doing it for you, but then try to understand the choices that were done) and compose and integrate them that coding everything from the ground up. You obviously still have to write code but at another level and directly linked to your business. And it will be for you a first step toward a larger vision of software system and toward the software architect role. This also help keeping a good separation of concern in your application design (another golden rule, hey! we are starting to see a common link between all this and it probably confirm the more I will be writing on the subject!)   

So that's enough for now and hope to have caught you attention and you will join me for later post on other golden rules!!