African computing devices and hardware

It’s nice to blog again, I have been away for a while but this is because I have been quite busy, in-between travelling to perilous lands (Afghanistan...twice) , studying and having a handful but cheerful son to take care of when I am in Nairobi - I have been engaging on a project that I have had a burden on for quite some time. I once heard a saying – “Africans have been conditioned to consume what they do not produce and produce what they do not consume” and it really struck me, as I looked around I realized how true the statement was/is. So I made a vow to change that as much as I can in my domain - technology. What do you think of when we talk about technology in Africa ? I am sure many of us think of IT, but is Technology is not limited to just IT. Ndubuisi Ekekwe (a patent holder on a microchip) once wrote an article saying “IT is more consumption based, the fundamental technology that drives IT is microelectronics and we have to participate in that domain. We have to get there...” and out rightly declaring “Technology is not IT “ and thus in the same breadth I concur that while Africa has made great strides in making our own software and sharing the same because we have open source projects such as Ushahidi that have been used globally to crowd source information. We are not yet there because we still import devices from somewhere else. We are happy to run our software on Hardware which at best we have theoretical knowledge of what is going on in them. I agree with Ndubuisi, that we as African have been shy and slow to go into that domain. I believe that hardware manufacturing is a win-win setup even for Africans for the following reasons.

1.           While hardware manufacturing is not as profitable sometimes as software is (it’s not exactly inventing facebook), it’s possible to get many versions of hardware existing in the same market due to market segments and thus everyone gets paid as opposed to software services where there are single big players and everyone else seems to be making losses.
2.           Hardware is something that you can show to your mum and relatives. Any software developer in Africa knows that it’s very difficult to explain what they actually do to their relatives. However, if you conceive and manufacture a device – you have a physical manifestation of your work and not just stories.

In order to make this posting much more than a runt but an avenue that I can share what I have learnt so far. The project I have been engaged in is the making of a computing device. Prima facie that sounds really big but it’s not as big as it seems. I have researched, read and read even more on how to get electronics working ever since I was inspired when I watched a 2009 video done by AllGo (http://armdevices.net/2010/07/23/indias-35-tablet-is-based-on-my-video/) on the tablet device that has a BOM (bill of material) of $35 this was before the Indian government release a variation of the same. I have been successful at getting most of the things running because of the existence of 4 things. I believe that these 4 things will enable Africans run African software on African devices:

1.  The first thing that has made it possible for a simple boy from Bahati in Nakuru, Kenya to design computing devices is the existence of information on the internet. The existence of the opensource tools to design devices, the existence of hardware projects and for the unscrupulous ones the use of Piratebay, isohunt or even emule to get Cadence Allegro for your PCB design. The existence of tonnes of reading materials ranging from simple schematics to complex device designs is a shot in the arm for any person looking to getting any device working.
2. The second thing that is paramount in making African hardware a reality is use of System on chip (SoC) processors. I believe that this is the single greatest step in hardware computing since the multicore processor. Basically a SoC processor is a chip that integrates all components of a processor on to a chip...yes you heard me – ALL, from RAM to the CPU, from CACHE memory to audio and video codecs. Some have GPUs and they are becoming multicore. This basically makes it easy to design a piece of electronic equipment without caring how to connect these components. What one needs to be armed with is the datasheet for your SoC of choice. e.g. http://cache.freescale.com/files/32bit/doc/data_sheet/IMX53CEC.pdf?pspll=1 . Some of the processor manufacturers such as freescale, have create reference designs and exposed schematics and PCB designs used to create the devices for all and sundry, this makes it possible for a person with a low R&D budget to get a device working right off the bat.
3. The 3^rd thing is the availability of Android. While the banner on this blog says “I love windows phone”, I believe Andorid is the Operating system of choice for small fish like me in making this device a reality. Android is open source and the existence of custom ROMs out there that are able to make your device look nice really easily is a boon to small fish and hobbyists. Processor manufacturers are supporting us to this end in making compilations that work with their SoCs. I don’t think we have the competence to write low level RISC statements that interface drives of devices such as cameras and the processors however we do have the competence to compile drivers for the Linux kernel that runs android and with the help of forums like xda port functionality on to our devices.
4.     Finally the last thing that makes it possible for us to create devices is the existence of ODMs, these are Original Design Manufacturers and not popular parties in some areas of east Africa. Because manufacturing is expensive....really expensive, one needs to leverage the existence of these factories that take your design and manufacture in bulk for you. I had initially wanted to do everything myself but found it impractical. Getting components such as Pixel Qi screens from the manufacturer was very expensive. The printing out of PCBs was cheaper ($17) but the mounting of components was close way over $250 per device. My dream device would cost upwards of $500 – this would be impractical. However when one harnesses the power of ODMs, a small company like mine is able to get devices manufactured cheaply due to the reputation of these manufacturers. The design remains yours. I believe this should be a temporary step in the dream of making African computation device manufacturing a reality. But the sooner we can get an African ODM working, the better for us. However, a device conceived by an African mind from casing to PCB and SoC to touchpanel but manufactured by a Chinese ODM is an African device! I believe it is analogous to a child conceived by 2 loving parents who are unable to take the pregnancy to full term but choose implant on their treasure in a surrogate mother’s womb for nurturing during the 9 months of gestation after which the surrogate mother gets paid and the baby is taken home by the biological parents. FYI...Apple does it...(anyone with an iDevice should read the back it says..ASSEMBLED IN CHINA)

 if harnessed properly, I believe that these 4 things will indeed create an opportunity for African minds to conceive devices that have at heart solutions to our problems and thus being a step in the right direction in making “Africans consume what they produce”.

Mango on Blackberry

After weeks of R&D work, I was finally able to put Mango on a Blackberry bold.

Windows 8

Microsoft has recently pulled the curtains off its next operating system code name “Windows 8” at the D9 conference last week, I watched the video on what it can do and my initial reaction was “Ehh, No comment!”.

Let’s face it Microsoft is playing catch up and according to a respectable friend of mine, they always have ever since DOS, Xenix, Windows, Sybase SQL Server, Zune, Xbox e.t.c. I am guessing tablet PCs and Smart Phones is the first thing they really pioneered in during the days of Microsoft 1.0 led by Bill Gates but their failure to innovate and their attempt to shrink the popular desktop Windows OS into tablets and “pocket PCs” and basically replaced the mouse with a stylus and this did not fare well with the customers and lost the market to Apple and Android. Consequently Windows 8 (and Windows Phone 7) represents an attempt to get back to get back into the tablet game and they have really done a great job at it and the following are aspects of it that stood out for me and comments on them.

1.    For those who don’t know yet – they utilized the Metro design as done in Windows Phone – which I like; I am of the opinion that the Tiles are a better approach to displaying information than iOS icons or Android widgets especially as done in “Mango”.

2.    The use of HTML5 and JS for Windows 8 app building virtually enables millions of HTML + JS developers to just up their existing skills to HTML5 and have skills useful for developing applications for Windows 8. This is a double edged sword judging by the reactions of traditional windows developers who use XAML and C# who see it as a betrayal by Microsoft of .NET for this new way of writing applications. Will the current set of developers embrace it without question or will it happen that they will make the kind of noise that followed the news that Microsoft was abandoning classic Visual basic during the birth of .NET? How does this affect the dream of having the same application running on both Windows Phone and Windows 8? It will really be useful to have 21K applications written (at the time of going to press) for Windows phone 7 available for Windows 8 off the bat rather than rebuilding them.

3.    The other is that they have enabled multitasking and the ability to run and use multiple applications simultaneously – this is huge, since both Android and iOS do not the later functionality. This is a great step and is in my opinion similar to the deep linking of apps to search results in “Mango”. Something that both Android and iOS don’t have as of now.

4.    Many pundits point are quick to point out that Window 8 provides backward compatibility with x86-x64 applications even though it is built to be run on ARM (for those computer scientist out there - you know how difficult/impossible it is to support code compiled for CISC on RISC. Both x86 and x64 are CISC instruction sets yet ARM is a RISC instruction set and thus having an application compiled for a CISC architecture running on RISC may not be easy but Microsoft claims to have pulled it off). My question is – what benefit is this on the tablet? Most of the older x86-x64 applications are not as touch friendly for tablets. I think this is an over kill but users do not need to use it if they don’t want it.

5.    The dream to have Windows 8 run on Tablets, Desktops and Servers seems a bit ambitious, I must admit having “One OS to rule them all, One OS to run them, One OS to bridge them all, And with the touch interface bind them'' Seems nice but an unnecessary effort as I don’t want to use my visual studio instance with touch. Hardware Keyboards and Mice are actually good and accurate peripherals useful for a workstation setup. I would hate to run SQL Server on Windows 8 as it was shown. I suspect that it may not sell well at an enterprise level.

Something worth noting is that Windows 8 presents the first “windowless” design for an operating system by Microsoft for desktops and tablets – whether it will succeed in both is a different matter. Hopefully Microsoft will listen to the community and release a better version during BUILD later this year in my humble opinion, they should release 3 versions of Windows 8 one for Tablets, one for Desktops and one for servers while having the latter 2 having a different user interface or “shell” else this is a bigger gamble that what Ballmer thought it was. What’s your take?

Need NoDo quick? No problem...

If you are  a Windows Phone 7 handset owner who has been patiently waiting for the ‘NoDo’  and are still waiting ChevronWP7 developer Chris Walshie has good news for you, He has created an application that combines all the updates (pre-NoDo 7008 all the way to NoDo update 2 7390) into a single package.   Check out his blog here. 

Some caveats are:

·        Make sure you select the RIGHT language for your device. To double check what your default language is, go to Settings > Keyboard and if your selected language is displayed in the Console app, you’re good to select it. If it isn’t in the list, DON’T flash it just yet.

·        If you’re updating from Version 7004, you need to run the Updater TWICE, this needs the preUpdate before we can flash NoDo.

·        This “might” work for HD2 owners, haven’t tried it out just yet.

·        There is NO revert process, again, flash at your own risk.

·        Disclaimer, use this at your own risk, if this voids your warranty I’m not being held responsible, blah blah all that junk.

Downloads for 32-bit and 64-bit Windows available, I used the 64-bit release.

I just installed it and found the process seamless my OS version is now 7.0.7390.0 

Update

One day after installation Zune asked me if I wanted an update. it went through the motions again to reinstall NoDo once more

Memcached on Windows.

As you may know Memcached is a distributed caching system that is used by major website out there (facebook et.al) and there are many articles out in the wild that handle this matter on windows, I will try and put in my experience and my lessons learnt. As you are aware -  memcached is not exactly meant to run on windows and thus we have to put up with ports of the original software that my not exactly be the best to run on a production environment. I started out with the http://code.jellycan.com/memcached/ build. It was kind of old since the last time it was updated was in November 2009. It worked for a while but I could not run it with a degree of surety on production, I figured it may possibly have had some optimization done on it and some bugs lurking in there that might have been resolved. So I decided to do some bit of research in an attempt to get the latest and greatest release of memcached for windows. I stumbled upon Membase this is one of the best Memcached like services, it is basically in two parts

1.    The Membase Server is a NoSQL database. That is basically a distributed key-value data store; it is designed and optimized for the data management needs of interactive web applications, so it allows the data layer to scale out just like the web application logic tier – simply by adding more commodity servers.

2.    Memcached is part of Membase Server, transparently caching data in front of its key-value database. You can configure Membase Server to provide only Memcached services and for there for skip the use of the NoSQL database.

I decided to use the later only as what I needed was the caching framework only, and this worked for a while and worked really well coupled with the nice intuitive administration portal that comes with the install – it was exactly what I was looking for...until I attempted to throw in a large dataset for caching and it failed, We quickly diagnosed that the issue was that all memcached services have a max of 1024kb size for items that need to be stored in them – this was not acceptable as we had started implementing a caching collections instead of individual items policy for our work. Apparently there is an argument/flag passed at start-up that instructs the memcached service to start accepting items that are larger than 1mb .

memcached.exe -I

But this particular flag was not available(availed) in the memcached service on the Membase distribution. So I was regrettably back on the road, looking for an build that was new and that had capability of accepting the argument for our work.

After sometime I came across an article on how to build the memcached service on windows and to this I said a big Hallelujah!! I executed steps outlined below to do my own build.

1.    Installed mysysgit. This in addition to installing git, it also installed a compiler capable of building a 32 bit version of memcached on windows. Since apparently Microsoft does not supply a C99 compliant C compiler…go figure.

2.    Installed libevent 2.0.10 (latest at the time) on my machine by executing the following commands (from within your msysgit-shell).

$ cd /tmp

$ tar xfz libevent-2.0.10-stable.tar.gz

$ cd libevent-2.0.10-stable

$ ./configure --prefix=/usr/local

$ make all

$ make install  

3.    Built memcached by checking out and compiling the source code

$ git clone git://github.com/trondn/memcached.git

$ git checkout -t origin/engine

$ make -f win32/Makefile.mingw

I run it by executing 

        $ ./memcached.exe -E ./libs/default_engine.s

Then tested it using telnet to port 11211 and issue the "stats" command to verify that it works! On the deployment environment I just included pthreadGC2.dll from the msysgit distribution and the libs/default_engine.so in the folder I wanted memcached to run on.


Now building a x64 bit release was not as easy and I gave up! 

Killing IE6

I am just done watching episode 94 of Ping on channel 9 and heard that Microsoft is doing all it can to make IE6 lose its market share (loved the catchphrase – “friends don't let friends use IE6”), Its a fairly belated attempt seeing as companies like Google have already joined the armada of companies that do not support IE6. To web developers, this is definitely a great thing and means that we will decreasingly stop creating cascading style sheets that is specifically meant to run on IE6 and below and endless hours of javascript debugging.

This means no more png alpha transparency fixes, no more....

.box {

   background: #00f; /* all browsers including Mac IE */

   *background: #f00; /* IE 7 and below */

   _background/**/: #0f0; /* IE 5.0 */

   _background:/**/ #f62; /* IE 5.5 only */

   _background/**/:/**/ #f61; /* IE 6 only */

   padding: 7px;

   color: #fff;

}

nonsense in CSS!! Welcome to the beginning of a standardized Internet!! –DO I HAVE A WITNESS?

On the flipside (for Microsoft), using the latest stats, it seems the loss of IE6 market share does not translate to the gain in market share of IE7+ browsers as Google Chrome appears to be growing almost at the rate IE is losing ground. (At this point I drop my well thought of pun of the week and the only reason I wrote this post!!)

Microsoft – be careful what you wish for because it may just CHROME true.

P.S there is a website out there that does real time countdown of IE6 Market share its called IE6Countdown that complements a bunch of websites that want IE6 dead they are I Dropped IE6 , IE6 Update and IE6 No more

Preventing Lazy and comment-less source code checking in subversion

I come from a background of using Visual Source safe as a tool for source control and had never really needed to setup a source control infrastructure prior to my assignment in Pakistan. So when I landed the job, I quickly downloaded and installed the Collabnet build of subversion. Then decided that like any software development team worth its salt, I would have to create software coding practices and procedures and one of which was the use of source control and thus formulated rules around checking in source code such as No check ins without comments, All comments must make sense blah blah blah. Later during my analysis of the check ins I realised that my team members were going against rules and were checking in code without comments or just lazy comments like “fixed” or “done” or “checked in” at which point I came to a crossroad – do I lay down the law at them for doing this or do I find an automated way of resolving this matter and I decided the later had a more long lasting effect – plus it stretched us, which is good. So I did my research and discovered that it was not direct provided (not a config change) but was possible by using hooks.

I created a file that had a bunch of excluded words as mentioned above saved it in c:\svn\excludedwords.txt and then created a pre-commit batch file that was supposed to be run prior to committing the change(duh!). The exact filename was Pre-commit.bat that was placed in the Hooks folder on SVN

The contents of the batch file were

rem Make sure that the log message contains some text.

set REPOS=%1

set TXN=%2

"C:\svn\SVNlook.exe" log -t %TXN% %REPOS% | FindStr [a-zA-Z0-9]

IF %ERRORLEVEL% EQU 0 GOTO OK

echo Your commit has been blocked because you didn't provide a log message  1>&2

echo Please write a log message describing the purpose of your changes and 1>&2

echo then try committing again. -- Thank you 1>&2

exit 1

:OK

rem Check if comment is in list of reserved words to not be used..

the above is meant to check for empty comments and would echo out correct error messages.

"C:\svn\SVNlook.exe" log -t %TXN% %REPOS% >comment

setlocal enabledelayedexpansion

Set SEPARATOR=

set COMMENT=

for /f "delims=" %%a in (comment) do ( 

    set currentline=%%a

    set COMMENT=!COMMENT!%SEPARATOR%!currentline!

)

FIND "%COMMENT%" "c:\svn\excludedwords.txt">Null

If %ERRORLEVEL% EQU 1 goto OK2

:Fail

echo Your commit has been blocked because the single word comment you provided is not allowed 1>&2

echo Line is -%COMMENT%- 1>&2

echo Please write a proper log message describing the purpose of your changes and 1>&2

echo then try committing again. -- Thank you 1>&2

exit 1

:OK2

rem Check that the author of this commit has the rights to perform

rem the commit on the files and directories being modified.

rem commit-access-control.pl "$REPOS" "$TXN" commit-access-control.cfg || exit 1

rem All checks passed, so allow the commit.

exit 0

The above was used to check if the comment was a single word or found in my excluded list of words.

So I quietly sneaked in the change and waited for responses, I got a few moans but explained later that it was important to follow rules.

10000 apps milestone and other interesting stats

Its been reported that the Microsoft market place has hit the 10000 apps milestone sometime yesterday and was at 10162 at the time i went to press - Kudos (even after locking out a huge number of potential developers)

the above charts should update automatically.

you can get the html for the above at http://www.windowsphoneapplist.com/stats/

WP7 spared at Pwn2Own Hackathon

At the annual Pwn2Own hackathon, IPhone and Blackberry failed as Android and WP7 were left standing as the hackers withdrew at the last minute citing to legal and other hindrances.

The Global Publisher Program

As I had ranted before - Microsoft does not allow developers from Africa and some areas of the middle east and Asia to register as developers for WP7, this was a short sighted bummer coz it affects the platform as the assumption that those regions do not have developers is silly and gives android an upper hand (p.s. I have already started running Eclipse on my laptop, reading the professorial android application development and a cheap android tablet)
If you are thinking of a rich market for mobile/smart phone look no further than these places.
Anyway - a couple of days ago there was some movement  in that front as now you can register with a third party service called Yalla Apps that will publish your apps for you and take 20% of the earnings (after Microsoft's 30%) so you get 80% of what you would normally receive. You have to pay $99 for 100 credits, each app submission costs 25 credits wether it's a free or paid app, and development device unlocking costs 50 credits per device and is accomplished using remote desktop access from Yalla Apps. Its not the best suited solution but its the best we have for now.

Way Forward

Today represents the last day of my work in Pakistan for the foreseeable future and the end of the contract I have been on for almost an year, I still don't have anything solid to fall on. So the tomorrow is the first day of the rest of my life and consequently it will really be the first time in my life that I have been in between jobs and nothing to peg my employment insecurities on. I am kinda looking forward to it...how will I react? How will I cope, will I will be freaked out, I hope I will be able to cut it - nothing seems to appeal to me just as yet. A couple of questions lurk at the back of my mind....

1. Will I go back to international consulting?- Maybe - subject to opportunities,
2. Will I go back to local support staff status - unlikely (but I have a couple of mouths to feed so its not out of the case - but it will be quite a sellout) ,
3. Will I go back to the private sector? - I don't Know - but I don't think so, slaving away for someone else,
4. Will I attempt to do something on my own? - I hope so!! Thus What will I do? I need the muses to inspire!! (this can be linked up with No. 1 above)

so, the rest of my life is a canvas waiting for me to paint it....let the games begin.

Database related Issues experienced using EF 4.0 and Transaction scope objects.

As I had blogged previously, we have just gone live in certain places in Pakistan with the Computerized Electoral Roll System , a project I have been consulting on in the last couple of months. Conseqently yours truly yesterday (07^th March 2011) traveled to Osama bin laden’s backyard – Peshawar in Khyber-Pakhtoonkhwa for a go live test, demo, walk through all wrapped up in one that failed coz the links that connect the provinces’ to the capital were down and we had to settle for the use of a development copy and database for all of the above.

But running towards this go live we had experienced some problems. This is an attempt at logging them and documenting them of all and sundry – most of this is not new nor am I the first to resolve them but I will show you how I resolved them.

The first problem I run into months ago while using transactions was that I seemingly could not execute an insert, update or delete sp (imported function) when in the transaction context.

e.g.

var datactx = ContextHelper<CERSEntities>.GetCurrentContext();

using (var scope = new TransactionScope())

{

List<VOTER> updatedvoters = new List<VOTER>();

foreach (var voter in voterEntity)

{

datactx.UpdateVoters(Param1,Param2,...);

}

scope.Complete();

}

Was causing issues, until I discovered that EF 4.0 was silly and that it somehow expected a

insertedvoter.FirstOrDefault();

After each call to the store procedure more info on this can be found here.

Secondly we run into a problem in that we had been developing had been on SQL Server 2008 but the target database was SQL 2005 - this posed two issues, first a more obvious issue we received a message that

"Type datetime2 is not a defined system type"

Datetime2 is not available in SQL 2005 so I quickly redid the EDMX, and changed its version by opening the edmx file using a text editor and changing the provider manifest to 2008

<edmx:Edmx Version="2.0" xmlns:edmx="http://schemas.microsoft.com/ado/2008/10/edmx">

<edmx:Runtime>

<edmx:StorageModels>

<Schema Namespace="CERSModel.Store" Alias="Self" Provider="System.Data.SqlClient" ProviderManifestToken="2008" xmlns:store="http://schemas.microsoft.com/ado/2007/12/edm/EntityStoreSchemaGenerator" xmlns="http://schemas.microsoft.com/ado/2009/02/edm/ssdl">

Saved it change it to ProviderManifestToken="2005" and recompiled DAL

The second problem was more subtle and only happened in certain screens i.e. the transactions we were running were now becoming distributed. We traced it to the TransactionScope object. It was now all over suddenly escalating transactions to distributed transactions. I have been using the TransactionScope ever since I discovered it, because it’s a nice neat way of providing a neat way to do transactions while also giving your code the ability to reuse ambient transactions (i.e. transactions already created by caller methods) while supporting method level transactions just in case the method is called by a method that does not have a transaction.

But because we were not spanning database nor using multiple connection strings – the obvious things that cause normal transactions to escalate into distributed transactions, this was problematic we later dug up the reason as being that the issue was happening because the target db server was a SQL 2005. This posed a problem that would either need to

1. Upgrade the target database server to 2008 – the cost implications and the time did not make it easy on us (we were quite tempted to run the prod database of 80 million voters on SQL Server 2008 development edition).

2. Replicate all the code that was being used in methods that used ambient transactions – this proved to be quite untidy not to mention unprofessional.

3. Create a customized transaction scope object that would be used to do exactly what the TransactionScope object does but in the context of our use case.

I thought the latter was neater and would be a nice challenge and had a couple of hours to kill so I decided to do my own transaction scoping mechanism by – this is how I did it.

1. I created an extension method that would be attached on a data context and this was it

public class OurStaggeredDBTransaction : MarshalByRefObject, IDbTransaction

{

private const string TransactionCountKey = "TransactionCount";

public IDbTransaction Transaction { get; set; }

private bool CommitCalled = false;

public OurStaggeredDBTransaction(IDbTransaction originaltrans)

{

Transaction = originaltrans;

}

private void ResetCount()

{

HttpContext httpContext = HttpContext.Current;

if (httpContext != null)

{

string contextTypeKey = TransactionCountKey + typeof(OurStaggeredDBTransaction).Name;

if (httpContext.Items[contextTypeKey] != null)

{

httpContext.Items[contextTypeKey] = 0;

return;

}

else

{

throw new ApplicationException("There is no Nested Transaction in Http Context available");

}

}

throw new ApplicationException("There is no Http Context available");

}

public void IncreaseCount()

{

CommitCalled = false;

HttpContext httpContext = HttpContext.Current;

if (httpContext != null)

{

string contextTypeKey = TransactionCountKey + typeof(OurStaggeredDBTransaction).Name;

if (httpContext.Items[contextTypeKey] != null)

{

httpContext.Items[contextTypeKey] = ((int)httpContext.Items[contextTypeKey]) + 1;

}

else

{

httpContext.Items.Add(contextTypeKey, 1);

}

return ;

}

throw new ApplicationException("There is no Http Context available");

}

private void DeductCount()

{

HttpContext httpContext = HttpContext.Current;

if (httpContext != null)

{

string contextTypeKey = TransactionCountKey + typeof(OurStaggeredDBTransaction).Name;

if (httpContext.Items[contextTypeKey] != null)

{

httpContext.Items[contextTypeKey] = ((int)httpContext.Items[contextTypeKey]) - 1;

return;

}

else

{

throw new ApplicationException("There is no Nested Transaction in Http Context available");

}

}

throw new ApplicationException("There is no Http Context available");

}

private int GetCount()

{

HttpContext httpContext = HttpContext.Current;

if (httpContext != null)

{

string contextTypeKey = TransactionCountKey + typeof(OurStaggeredDBTransaction).Name;

if (httpContext.Items[contextTypeKey] != null)

{

return (int)httpContext.Items[contextTypeKey];

}

else

{

throw new ApplicationException("There is no Nested Transaction in Http Context available");

}

}

throw new ApplicationException("There is no Http Context available");

}

public void Commit()

{

CommitCalled = true;

if (GetCount() > 1)

{

DeductCount();

}

else

{

Transaction.Commit();

}

}

public IDbConnection Connection

{

get { return Transaction.Connection; }

}

public IsolationLevel IsolationLevel

{

get { return Transaction.IsolationLevel; }

}

public void Rollback()

{

CommitCalled = false;

ResetCount();

Transaction.Rollback();

}

public void Dispose()

{

if (CommitCalled && GetCount() >0)

{

//do nothing

//Transaction.Dispose();

CommitCalled = false;

}

else

{

Transaction.Dispose();

}

}

}

public static OurStaggeredDBTransaction BeginTransaction(this CERSEntities objcontext)

{

HttpContext httpContext = HttpContext.Current;

if (httpContext != null)

{

string contextTypeKey = ObjectContextKey + typeof(CERSEntities).Name;

if (httpContext.Items[contextTypeKey] == null)

{

if (objcontext.Connection.State != System.Data.ConnectionState.Open)

objcontext.Connection.Open();

httpContext.Items.Add(contextTypeKey, new OurStaggeredDBTransaction(objcontext.Connection.BeginTransaction()));

}

//increase the count for each time requested

((OurStaggeredDBTransaction)httpContext.Items[contextTypeKey]).IncreaseCount();

return (OurStaggeredDBTransaction)httpContext.Items[contextTypeKey];

}

throw new ApplicationException("There is no Http Context available");

}

2. Created an extension method that could be used on a datacontext object (CERSEntities in our case)

public static OurStaggeredDBTransaction BeginTransaction(this CERSEntities objcontext)

{

HttpContext httpContext = HttpContext.Current;

if (httpContext != null)

{

string contextTypeKey = ObjectContextKey + typeof(CERSEntities).Name;

if (httpContext.Items[contextTypeKey] == null)

{

if (objcontext.Connection.State != System.Data.ConnectionState.Open)

objcontext.Connection.Open();

httpContext.Items.Add(contextTypeKey, new OurStaggeredDBTransaction(objcontext.Connection.BeginTransaction()));

}

//increase the count for each time requested

((OurStaggeredDBTransaction)httpContext.Items[contextTypeKey]).IncreaseCount();

return (OurStaggeredDBTransaction)httpContext.Items[contextTypeKey];

}

throw new ApplicationException("There is no Http Context available");

}

3. Changed all transaction scope objects to be as follows

using (var scope = datactx.BeginTransaction())

{

....................

scope.Commit();

}

This worked like a charm, as I reused the same transaction and kept count of callers and failure in one resulted in failure in all but success in on would just reduce the count of callers.

It could do with some more work, but it seems to work as of now – which I am happy with. Feel free to correct, critic the above code.

I will be on my way to Nairobi in a couple of hours….looking forward to holding my wife and baby boy in my hands!!!