All posts by : Charles Young

1 of 48 | MS BRE: Controlling rule side effects - For almost two years now, I've been intending to write an article about the mysterious 'side effects' flag used in Microsoft Business Rule Engine policies.  Microsoft documents this feature (see http://msdn2.microsoft.com/en-us/library/aa559124.aspx), and describes very briefly how to control it.   The mystery that surrounds this flag arises because it is represented by an attribute named 'sideeffects' in Microsoft's BRL (Business Rule Language) although it actually controls a caching mechanism, and because Microsoft has not provided access to the flag in their Rules Composer, thereby giving the impression that it is not a 'first-class' feature of rule definitions.  ......

2 of 48 | Microsoft BRE: Fact Identity in the Microsoft Rules Engine, or how the author chased a non-existant bug - I recently had reason to revisit the exact mechanisms Microsoft use when you assert facts to the Microsoft Rules Engine.   I was discussing stuff on-line with a fellow rules enthusiast when a terrible thought occurred to me.   Can the MS BRE always uniquely identify each different fact, or is there a chance that sometimes it might confuse two facts with each other? For a couple of days, I was convinced that I had stumbled on a significant bug.   Indeed, at one point, I thought there was such a serious problem that I would have to recommend to my company that we desist from any further use of Microsoft’s rules engine.   Melodramatic, huh!  &......

3 of 48 | MVP Global Summit Day 4 - And so for my final report from the MVP summit.    For the BizTalk MVPs, day four started with a Q&A session with product team members.    A number of issues were discussed centred on the recurrent themes of evolving a coherent strategy across the Connected Services Division and the more effective inclusion of the MVP community into the feedback loop.   From my perspective, the BizTalk MVPs must surely be a valuable, if rather under-utilised, resource for CSD.   The collective wisdom and experience bought together in the Adams room in building 43 over the last couple of days represents decades of person-year experience in applying a cent......

4 of 48 | MVP Global Summit Day 3 - Day three of the MVP summit was held at the Microsoft Campus.   Things started badly with a long and slow bus ride through heavy traffic leaving me with no time for breakfast when I finally arrived at the conference centre.   I boarded the shuttle for building 43 to find most of my fellow BizTalk MVPs (the ones who have been staying in downtown Seattle since the weekend) equally late, and we arrived en masse about 15 minutes into the first session.    Jesus Rodriguez was on his feet presenting the forthcoming WCF adapter SDK with a particular focus on building LOB adapters with metadata harvesting and dynamic, consumer-orientated contracts.   Son......

5 of 48 | MVP Global Summit Day 2 - Day two of the MVP summit is over.   We were at the Washington State Convention & Trade Centre all day, but will be decamping to the Redmond campus tomorrow.   The day started with an unscheduled bout of ‘pre-match’ chanting from the Canadian MVPs.   They are an excitable crowd, and have spent much of the day ensuring that we all know which country they come from (Canada, I believe).    It appears that all Canadian MVPs (with the exception, I am glad to report, of Brian Loesgen) wear identical clothing.   Very strange. VP Richard Kaplan got things underway informing us that the conference is being attended by 1,700 MVPs from 90 cou......

6 of 48 | Name-dropping in Seattle - Day one of the 2007 MVP Global Summit - I'm in soggy Seattle at the MVP Global Summit, and, like so many of my fellow MVPs, it seems appropriate to keep some kind of daily journal - you know the form - let you know how fortunate I am to be on a big Microsoft freebie, and how unfortunate you are to, er..., not be...and, of course, get a bit of name-dropping in as well. The first round of name-dropping has nothing to do with the summit.  A week ago I was at the Microsoft Architect Insight conference at the Celtic Manor outside Newport, Wales.   The Celtic Manor is famous for golf and is the venue for the 2010 Ryder Cup.   It is also famous, these days, for software architects working on the Microsoft platf......

7 of 48 | Rules engines and dependancy injection - a response to Nick Malik - Nick Malik published a thought-provoking article on rules engines recently.   You can read it at http://blogs.msdn.com/nickmalik/archive/2007/03/06/perhaps-it-is-time-to-declare-victory-in-the-battle-of-rules-engines-vs-dependency-injection.aspx.   He adopts a fairly negative attitude to rules engines in general, suggesting various reasons why he considers that they are not often useful.  His preferred route is to use dependency injection patterns, implementing rule logic in code components that are then loaded in some dynamic or configurable fashion into consuming applications.   I believe Nick is quite wrong to contrast rules engines and dependency injectio......

8 of 48 | Whitepaper: Rules Processing & BPM: An Architectural Perspective - Over the last few weeks, I've been working on a whitepaper which SolidSoft has published today on our web site.  It's been published to coincide with the Microsoft Architect Insight conference at Newport which started today.   SolidSoft is one of the event sponsors, and I spent the morning delivering a workshop looking, from an architectural perspective, on the use of rules engines in business process management.   It seems to me that while there is lots of guidance and information on rules processing in BPM for business stakeholders, and some for business and enterprise architects, there is far less material orientated towards solution architects.   I've ......

9 of 48 | BizTalk Server 2006: The Compensation Model - The week before last, I spent some time updating an existing document on BizTalk exception handling for a client.   I added a couple of pages on the use of compensation.   I hoped to be able to reference a comprehensive article or paper on the subject, but after spending some time searching,  I largely drew blanks.   As always, the Microsoft documentation proved fragmented, terse and incomplete, although it has certainly improved since BizTalk 2004 days.   The small (but growing) number of BizTalk books did little better.    A few blog articles describe the compensation model to some degree.  There are a handful of academic pa......

10 of 48 | BizTalk 2006: Cool content... - So, there I am, sitting next to my boss, Andy, at work.  He's just downloaded the electronic version of a BizTalk book he's bought.   It's called "Pro BizTalk 2006" from Apress, and its written by George Dunphy and Ahmed Metwally.   Andy draws my attention to the chapter on the Microsoft Rules Engine.   I've got an interest in this piece of kit, so I start flicking through the pages to see what the chapter is like.   Not too bad at all.  Oh look, they've even got a section starting on page 290 that discusses how to use XPaths effectively to handle XML facts.   Good stuff.   I've blogged on this once or twice myself, and I......

11 of 48 | Wikipedia article on Rete - While I'm on the subject of rules engines (which seem to be my main blogging topic currently), I should report that during the last two or three weeks, I took the plunge and expanded (rather a lot) the Wikipedia article of the Rete algorithm.   See http://en.wikipedia.org/wiki/Rete_algorithm.     Originally, I used the text of an explanation I wrote a year or so ago.   I got some kickback on that, with claims of inaccuracy and other claims that the text was too convoluted (what, me write convoluted content - impossible!).   The original text wasn't inaccurate, but it was less comprehensive than it should have been, and lacking clarity in pla......

12 of 48 | MS BRE: Further Issues with XPath Selectors in the Microsoft Business Rules Engine - This article supplements an earlier article, posted a couple of weeks ago (http://geekswithblogs.net/cyoung/articles/90102.aspx), on issues concerning the use of XPaths to map between the hierarchical data structure of an XML document and the relational view of 'facts' in the Microsoft Business Rules Engine.   As I suggested in the introduction to that article, I have repeatedly been asked to troubleshoot MS BRE issues which turn out to be related to the use of XPaths.   Earlier this week, I received another request for help.   The symptoms and solution to the problem are worth recording because they provide greater insight into this topic. http://geekswithblo......

13 of 48 | MS BRE: Two new posts - Using XPaths and handling Negation as Failure - I've published two Microsoft Business Rules Engine-related articles today (nothing like a long weekend in a hotel). Negation-as-Failure and the Microsoft Business Rules Enginehttp://geekswithblogs.net/cyoung/articles/90100.aspxNegation can be a surprisingly problematic issue in the world of rules.   This article looks at one type of negation, generally referred to  as ‘negation as failure’ (NaF), and discusses the implications for the Microsoft Business Rules Engine (MS BRE).   In summary, we shall see that MS BRE fails to provide direct support for this type of negation, and as a consequence, the Microsoft Business Rule Language (MS BRL) is l......

14 of 48 | BizTalk: Conditional Compilation in Orchestrations - Anthony Pounder asked me if you can do conditional compilation in Biztalk orchestrations.   The answer is yes, but you have to edit the XLANG/s in the .odx file directly.   This is not functionality that is surfaced in the orchestration designer.     I wrote an article on XLANG/s a long time ago when I was still fairly new to BizTalk, and at the time I thought it would probably be a useful technique to be able to edit XLANG/s textually.   It turns out that almost all the XLANG/s functionality is surfaced in the orchestration designer.   This is one feature which isn't.   BizTalk orchestration currently p......

15 of 48 | MS BRE: Using ‘OR’ in MS BRE Rules - This article explores and sheds some light on a feature of the Microsoft Business Rules Engine which I consider to be important in understanding the semantics of rules.   This is the use of ‘or’ to create a group of conditions within a rule.   We will see that ‘or’ has a very specific meaning in Microsoft’s rule engine and that this meaning may not be quite what you might have expected.   We will also see how the MS BRE simplifies the model, making rule creation more intuitive than it might otherwise have been, and we will compare and contrast the use of ‘or’ in the Microsoft Business Rule Engine with the use of ‘......

16 of 48 | Handling Exclusive XML Canonicalisation in .NET 1.1 - A colleague is currently extending an existing .NET 1.1 application, and is adding functionality to handle SAML tokens provided by an identity provider web site.   He came across the problem of handing exclusive XML canonicalisation in the older version of the framework.   Microsoft supports the use of pluggable 'transform' classes to handle XML digital signature transforms (as specified using the element in the XML Digital Signature standard.   The trouble is that version 1.1 of the framework does not contain a transform class for exclusive XML canonicalisation.   Every time he tried to validate the digital signature in the token he got an error mess......

17 of 48 | Rules: A response to James McGovern's questions - I recently came across a post (http://duckdown.blogspot.com/2006/01/outstanding-questions-on-rules-engines.html) from James McGovern dating back to the beginning of the year is which he had asked a number of questions about Rules engines.   As Rules engines have become a subject of some interest to me over the last eighteen months or so, I though I would have a go at providing some answers.   In my own inimitable style, I of course wrote far too much to be accepted as a comment on James' web site (sorry, James)!   So I've expanded my replies a bit more and posted them here at http://geekswithblogs.net/cyoung/articles/76795.aspx.   I hope they are of s......

18 of 48 | WWF: Comparing WWF rules and the Microsoft Business Rule Engine - In Microsoft`s Windows Workflow Foundation,rules are executed through a sequential, rather than an `inferencing` engine. Although WWF rule processing bears a superficial resemblance to rule processing in the Microsoft Business Rules Engine (MS BRE), there are profound differences. This article attempts to explain the fundamental differences, and to provide some insight into the strengths and weaknesses of each approach....

19 of 48 | MS-BRE: Here are the results for my port of Peter Lin`s tests - For those following the debate on the implementation of the Rete algorithmin the Microsoft Business Rules Engine, you may be aware that I undertook to port some CLIPS/Jess tests provided by Peter Lin to the MS-BRE and to publish the results. This follows on from the original article I published here. My results for the ported tests are documented here. They show virtually identical scaling behaviour between Jess and the MS-BRE....

20 of 48 | BizTalk Server 2004: TBG2BTS 1.3 - Alan Smith has published version 1.3 of the Bloggers Guide to BizTalk.   Well done Alan....

21 of 48 | BizTalk Server 2004: Loopback pipeline processing - Gregory Van de Wiele has come up with no less than three different ideas (one of the from Scott Colestock) on invoking BizTalk pipelines with loop-back from within an orchestration.   All excellent stuff....

22 of 48 | BizTalk Server 2004: Loopback pipeline processing - Gregory Van de Wiele has come up with no less than three different ideas (one of the from Scott Colestock) on invoking BizTalk pipelines with loop-back from within an orchestration.   All excellent stuff....

23 of 48 | BizTalk Server 2004: New Microsoft courses - As an ex-MCT, I like to keep an eye on the training courses offered by Microsoft.  Two new BizTalk Server 2004 courses have been launched a week or so ago.   These are: MS2157 - Developing E-Business Solutions Using Microsoft BizTalk Server 2004 5 days - A development course covering the basics of BizTalk development.   It appears to offer quite a reasonable introduction to the subject.   The labs appear to be a modified subset of the original Microsoft BizTalk labs published back in beta-times. MS2158 - Deploying and Managing E-Business Solutions Using Microsoft BizTalk Server 2004 2 days - I`ve yet to see the material for this....

24 of 48 | BizTalk 2004: New version of the Bloggers` Guide to BizTalk - Congratulations to Alan Smith for publishing the November edition of the Bloggers` Guide to BizTalk.   There are several new contributers, and lots of new material.   I was surprised at just how extensive the information in this digest is becoming, after only the first update.   Excellent stuff....

25 of 48 | BizTalk 2004: New version of the Bloggers` Guide to BizTalk - Congratulations to Alan Smith for publishing the November edition of the Bloggers` Guide to BizTalk.   There are several new contributers, and lots of new material.   I was surprised at just how extensive the information in this digest is becoming, after only the first update.   Excellent stuff....

26 of 48 | BizTalk Server 2004: New Microsoft courses - As an ex-MCT, I like to keep an eye on the training courses offered by Microsoft.  Two new BizTalk Server 2004 courses have been launched a week or so ago.   These are: MS2157 - Developing E-Business Solutions Using Microsoft BizTalk Server 2004 5 days - A development course covering the basics of BizTalk development.   It appears to offer quite a reasonable introduction to the subject.   The labs appear to be a modified subset of the original Microsoft BizTalk labs published back in beta-times. MS2158 - Deploying and Managing E-Business Solutions Using Microsoft BizTalk Server 2004 2 days - I`ve yet to see the material for this....

27 of 48 | BizTalk Server 2004: The ten commandments of pipeline stream processing - Are you new to BizTalk pipeline processing  The `ten commandments` should prove helpful in avoiding some of the potential pitfalls.   Don`t take them too seriously, though.   The idea is simply to make you stop and think carefully before implementing inherently dangerous designs....

28 of 48 | BizTalk Server 2004: The ten commandments of pipeline stream processing - Are you new to BizTalk pipeline processing  The `ten commandments` should prove helpful in avoiding some of the potential pitfalls.   Don`t take them too seriously, though.   The idea is simply to make you stop and think carefully before implementing inherently dangerous designs....

29 of 48 | BizTalk Server 2004: Receive Pipeline woes v2 - A few days ago I posted an article on certain behaviours we had observed and investigated in relation to BizTalk receive pipelines. If anyone has been reading the feedback to the post, you will be aware that since then I’ve managed to make some further headway in this matter. My previous article simply described the behaviour and offered some speculation. I now know more about the causes. This new article is intended to replace the previous article....

30 of 48 | BizTalk Server 2004: Receive Pipeline woes v2 - A few days ago I posted an article on certain behaviours we had observed and investigated in relation to BizTalk receive pipelines. If anyone has been reading the feedback to the post, you will be aware that since then I’ve managed to make some further headway in this matter. My previous article simply described the behaviour and offered some speculation. I now know more about the causes. This new article is intended to replace the previous article....

31 of 48 | BizTalk Server 2004: Receive Pipeline woes - In the last few weeks, we`ve encountered a set of problems when using custom pipeline components in Receive pipelines.   After some testing, I have managed to produce a fairly definitive description of the behaviour we have encountered.   I have no very compelling explanation for what we have found, but the problems are entirely repeatable, and it is obvious from looking at BizTalk newsgroups that we are not the only people who have suffered from these problems.   To find out more, read the article....

32 of 48 | BizTalk Server 2004: Receive Pipeline woes - In the last few weeks, we`ve encountered a set of problems when using custom pipeline components in Receive pipelines.   After some testing, I have managed to produce a fairly definitive description of the behaviour we have encountered.   I have no very compelling explanation for what we have found, but the problems are entirely repeatable, and it is obvious from looking at BizTalk newsgroups that we are not the only people who have suffered from these problems.   To find out more, read the article....

33 of 48 | BizTalk Server 2004: FTP guaranteed delivery - The BizTalk Server 2004 FTP adapter offers a `guaranteed delivery` feature, the details of which are not documented by Microsoft.  The mechanism is very straightforward, however, and involves the use of a temporary folder.   Files are staged by BizTalk in this folder before being moved to the destination folder.   BizTalk supports this for both Send and Receive handlers.  To use this feature, simply set the "Temporary Folder" property of the FTP adapter.   For Send ports, this will be the name of an FTP folder on the server, rather than a local folder. The main advantage of using this feature is that retries can be performed in the event of a transport failure, with multiple copies of the ......

34 of 48 | BizTalk Server 2004: FTP guaranteed delivery - The BizTalk Server 2004 FTP adapter offers a `guaranteed delivery` feature, the details of which are not documented by Microsoft.  The mechanism is very straightforward, however, and involves the use of a temporary folder.   Files are staged by BizTalk in this folder before being moved to the destination folder.   BizTalk supports this for both Send and Receive handlers.  To use this feature, simply set the "Temporary Folder" property of the FTP adapter.   For Send ports, this will be the name of an FTP folder on the server, rather than a local folder. The main advantage of using this feature is that retries can be performed in the event of a transport failure, with multiple copies of the ......

35 of 48 | BizTalk Server 2004: Using the mapper for complex transforms - don`t!! - In all these months of living in BizTalk 2004 land, it is only recently that I have had occasion to do something serious with the BizTalk mapper - and I am not impressed.   I had a requirement to transform an input consisting of multiple records which use attributes to capture field values into an output where, for each input record, the transform creates two similar, but different, records, and then an arbitrary sequence of additional records for those fields in the input which have a value.   Bit of a mouthful, that, but the point is that the output structure was quite different to the input structure. I merrily created a map to do the work.  I worked out I needed to employ the Table Loop......

36 of 48 | BizTalk Server 2004: Using the mapper for complex transforms - don`t!! - In all these months of living in BizTalk 2004 land, it is only recently that I have had occasion to do something serious with the BizTalk mapper - and I am not impressed.   I had a requirement to transform an input consisting of multiple records which use attributes to capture field values into an output where, for each input record, the transform creates two similar, but different, records, and then an arbitrary sequence of additional records for those fields in the input which have a value.   Bit of a mouthful, that, but the point is that the output structure was quite different to the input structure. I merrily created a map to do the work.  I worked out I needed to employ the Table Loop......

37 of 48 | BizTalk 2004 recovery: Works well, but beware of HAT! - I`ve spent some time in the last two days testing the resilience of a BizTalk production environment.  The environment consists of a two-box BizTalk 2004 server group and a two-box (active-passive) SQL cluster.  Testing primarily consisted of rebooting machines, moving SQL cluster groups and, best of all, pulling power cables out of the wall while creating large number of files in a drop folder.  We tried several failure scenarios for each of the four machines, and checked carefully for `lost` messages and any other problems. I`m glad to report that the testing was successful.  At one point, we thought we had lost a single message, but the problem proved spurious.  When we killed a process ......

38 of 48 | BizTalk 2004 recovery: Works well, but beware of HAT! - I`ve spent some time in the last two days testing the resilience of a BizTalk production environment.  The environment consists of a two-box BizTalk 2004 server group and a two-box (active-passive) SQL cluster.  Testing primarily consisted of rebooting machines, moving SQL cluster groups and, best of all, pulling power cables out of the wall while creating large number of files in a drop folder.  We tried several failure scenarios for each of the four machines, and checked carefully for `lost` messages and any other problems. I`m glad to report that the testing was successful.  At one point, we thought we had lost a single message, but the problem proved spurious.  When we killed a process ......

39 of 48 | BizTalk Super Efficient and Effective Deployment - When BizTalk Server 2002 introduced SEED package technology, I spent quite some time trying to find out what `SEED` stood for.   A couple of years later, I have at long last got the answer...and I don`t believe it!!   See the title of this post for more info :-)...

40 of 48 | BizTalk Super Efficient and Effective Deployment - When BizTalk Server 2002 introduced SEED package technology, I spent quite some time trying to find out what `SEED` stood for.   A couple of years later, I have at long last got the answer...and I don`t believe it!!   See the title of this post for more info :-)...

41 of 48 | Quick Tip: How to control XML encoding in BizTalk Server 2004 - A classic mistake in BizTalk is to think that you can control more than you really can through schemas.   For example, although you can specify default values within a schema (say for a attribute value), this has no effect on message construction and output.  Schemas are for validation, mapping, data-typing.etc.   They don`t control message construction or value output.A related issue that came up recently was how to control XML encoding.   BizTalk defaults to UTF-8 for XML encoding, and a client of ours had been trying to change this by modifying their XSDs.   This does not work.  You control XML encoding by using the XML assembler within the send pipeline .   By default, the XML Assembler......

42 of 48 | Quick Tip: How to control XML encoding in BizTalk Server 2004 - A classic mistake in BizTalk is to think that you can control more than you really can through schemas.   For example, although you can specify default values within a schema (say for a attribute value), this has no effect on message construction and output.  Schemas are for validation, mapping, data-typing.etc.   They don`t control message construction or value output.A related issue that came up recently was how to control XML encoding.   BizTalk defaults to UTF-8 for XML encoding, and a client of ours had been trying to change this by modifying their XSDs.   This does not work.  You control XML encoding by using the XML assembler within the send pipeline .   By default, the XML Assembler......

43 of 48 | Quick tip: How to submit messages to MSMQT locally - I`ve been investigating MSMQT and immediately ran into a basic problem.  I created an MSMQT Receive port and configured it appropriately.   I then tried to submit messages using the System.Messaging classes in .NET.   I couldn`t get this to work.   Every time I got an error message saying the MSMQ is not installed on my machine (which is quite true!).   I did some investigation, and soon found that indeed, you cannot submit messages to a local MSMQT Receive location using System.Messaging or any other API.   You could do this from another box which has MSMQ installed, but not from the local server.   Having said that, it is possible to set up MSMQ and MSMQT to run side-by-side on the same b......

44 of 48 | Quick tip: How to submit messages to MSMQT locally - I`ve been investigating MSMQT and immediately ran into a basic problem.  I created an MSMQT Receive port and configured it appropriately.   I then tried to submit messages using the System.Messaging classes in .NET.   I couldn`t get this to work.   Every time I got an error message saying the MSMQ is not installed on my machine (which is quite true!).   I did some investigation, and soon found that indeed, you cannot submit messages to a local MSMQT Receive location using System.Messaging or any other API.   You could do this from another box which has MSMQ installed, but not from the local server.   Having said that, it is possible to set up MSMQ and MSMQT to run side-by-side on the same b......

45 of 48 | BizTalk Server 2004 Configuration Management Report Generator - In case you`ve missed it, Scott Woodgate has published a new reporting tool on his blog site.   The BizTalk Server 2004 Configuration Management Report Generator offers both console and Windows.Forms interfaces, and an optional facility to exploit the SQL Server Report Services.  It provides three report types for orchestrations, schemas and hosts.  Each report type allows you to drill down to relevant configuration information, such as bindings between orchestration ports and messaging ports, or which orchestrations and maps uses a particular schema....

46 of 48 | BizTalk Server 2004 File Dump utility - BizTalk server 2004 compiles assemblies containing orchestrations, schemas, pipelines, maps, etc., by first generating transitory C# source code. A number of people have asked how you get access to the C# code generated by BizTalk Server 2004.   I have published a utility that will dump these files for you to an output folder of your choice.  This utility allows you to save copies of that source code for post-compilation inspection. The source code can be used to gain a deeper understanding of BizTalk Server 2004, or as a tool to troubleshoot and debug deeper problems in BizTalk-generated code. The BizTalk Server 2004 File Dump utility can be downloaded from the User Samples section of www......

47 of 48 | What is a BizTalk `application` - The Standard edition of BizTalk Server 2004 is restricted to "10 internal applications with up to 20 external trading partners".   A colleague just asked what the definition of an `application` is I believe the answer is as follows.   An `application` in BizTalk is a synonym for a host.  The term `Application` is used in relation to the MessageBox, whereas the term `Host` is used in management and administration of BizTalk.   Note that default name for the default in-proc host is BizTalkServerApplication.  The MessageBox maintains an `Application` table and BizTalk dynamically creates multiple queue tables in the MessageBox database for each application (i.e., each application has its own ......

48 of 48 | How messages work in BizTalk Server 2004 Orchestrations - The finer points of message handling in Biztalk Server 2004 are not always well understood.   This article attempts to shed some light on how messages are handled with Orchestrations, and the more confusing aspects of message initialisation....