MockingBird Futures – Mock BizTalk Adapters

MockingBird v2 has almost reached RTM. Just a few more days to make some final touches and it will be ready. The team has been discussing how to take it further and one thing that’s been on my mind for a long time is the topic of mock BizTalk adapters. What I would like to do is write some adapters with the WCF LOB Adapter SDK that link up with MockingBird’s simulation engine so we can then simulate various protocols such as SQL, Oracle, MSMQ, MQSeries etc.

The first question that anyone would ask me is “Why? “. Currently MockingBird works decently as a receiver from BizTalk in one way and solicit response mode. (It also supports duplex channels). If you have a one way message from BizTalk or a solicit response, then all you need is to replace the URL of the endpoint with the MB url and with the right config, the system will send back the messages you were expecting. So, why do we need to mock an adapter when we can simply avail of the WCF-Custom adapter?

While the first thing that comes to mind is that MB only handles the send side and does nothing on the receive side, i do think that there are many other reasons to go down the adapter route (on both the send and receive sides)

For the send side

1. Adapters will allow us to manipulate & use context properties. For situations where transport level correlation is being used (MQSeries, MSMQ etc), the adapter will let us force copy correlation identifiers to the response. Without this, we would need to have a queue listener that understood the MQ/MSMQ protocols and set properties accordingly.
2. Adapters will allow us to simulate transactional behaviour.
3. Minimizes the ‘intrusion footprint’ of the tool. Currently even if you were targeting SQL you would need to switch to WCF Custom and make a lot more binding changes. If we could adhere to the SQL adapter properties, it would reduce the amount of work. In fact all we should require is a change of url (eg: mbsql:// )
4. If an application interface doesn’t support web services, then piggy-backing on WCF LOB adapters will allow us to mock that system (assuming we are wrapping that system with the WCF LOB Adapter, we could potentially leverage that adapter to direct messages into mockingbird). So if there is a SQL/Oracle database, because we can connect to that via WCF-SQL , WCF-Oracle etc, we can just add the mock flavors of the same otherwise we would have to mock the entire SQL/Oracle protocols which is not feasible.

For the receive side

1. Although we can always create a test receive location with the file adapter, this is limited to ‘unit tests’. We cannot simulate other transport protocols (for example, polling sql. Also with queues (MQ/MSMQ) we would need an app that could send to the queue to activate the receive location.
2. We could extend an adapter to use the ‘Submit Direct’SDK  sample to send messages into BizTalk directly and configure this.
3. The context properties argument also applies here. A lot can be set artificially on the message. Similarly transactional behaviour could also be applied.

So, what about other current tools in this general area ?

1. Some of this kind of testing can be done with BizUnit (example : sending messages to a queue or reading from a queue). BizUnit could also be extended (example : a correlation aware queue listener) but BizUnit’s focus is on distinct steps that verify behaviour rather than on causing/forcing some behaviour which we can do via the adapters. The adapter approach also keeps this testing ‘within the boundary of Biztalk’ . while BizUnit will complement this nicely from the outside.
2. LoadGen can also help on the receive side. Again, LoadGen’s focus is on load/stress testing rather than functional behaviour. I think it may be possible to use LoadGen with Mockingbird (maybe as part of these adapters).
3. BizMock is another tool that is in similar territory. But having discussed MockingBird with Pierre Milet Llobet, the author of BizMock, I don’t see any overlap here. BizMock is focussed on providing a fluent interface to help with a TDD approach to BizTalk testing and on providing a mock adapter that is used within that test scope, but MockingBird’s adapters will be ‘proper’ infrastructure and integration test faciliators rather than a unit test tool.

Okay, so these are my thoughts on extending MockingBird into the arena of mock BizTalk adapters and I would really like to get feedback from the BizTalk community on this. What do you think of the idea? If you have some experience with the WCF LOB Adapter SDK (which I’ve only played with briefly) perhaps there’s some suggestions you can make or tips/gotchas you can make us aware of ? Is this an area you could get involved with (not necessarily have to contribute code, there are bandwidth constraints on all of us, but potentially send us suggestions, design ideas , maybe be an early tester etc?) .

Let me know. All feedback would be greatly appreciated.

BizTalk LoadGen vNext – Your input solicited

I’m doing a little groundwork for the team that is now developing and maintaining the BizTalk LoadGen tool. The team is planning for vNext and we would like to know from BizTalk developers what your thoughts are on features/functionality that could be added on. This will be added to the planning list and depending on demand, priorities, budget etc (all the usual balancing factors) it may turn up in the next version.

I’ll get the ball rolling here. One of the things that people have asked for in the past is a UI  to simplify adoption. Once you get familiar with the tool , the command line is all you need, which is the reason why the very early UI which you can see on a post by Richard Seroter was dropped. However, it may be useful to have some sort of UI to get people over the initial learning curve. But what kind of a UI should it be? The early UI was pretty much a simple property grid and a window to view the execution. Given that the XSD is available, it should be a simple matter for anyone writing a UI to plug a property grid that serializes out the XML. So is it worth the product team investing time in re-releasing a bog standard UI? How about wizards? Let me know and i’ll pass the info on.

BizUnit has LoadGen steps and the Performance Optimization Guide goes into a lot of detail on how to use BizUnit with LoadGen to test one of the BizTalk SDK end to end scenarios.

What other features would you like to see ? Do let me know via the comments on this post or the contact form and i’ll pass the requests on and keep you all updated.

MockingBird@SBUG

The UK SOA BPM User Group (SBUG) is holding a series of mini-meetings over the next few months. These are short live meetings / webcasts. I’m delighted to be presenting my web-service mocking tool , MockingBird at the next mini-meeting to be held on the 29th July.

I will be discussing how MockingBird assists and simplifies integration testing with web services, how it is used in Biztalk and non Biztalk scenarios, how the system works, how it can be extended and the roadmap.

Please check the event link on the SBUG site for details.  All are welcome to join (no membership needed). Hope to see a good turnout

BizUnit 3.1

BizUnit 3.1 is now released. (Actually its been out for over a week). There are a few bug fixes in this release and most notable is the addition of the following steps that Bram Veldhoen contributed.

• BizTalkSteps/ExecuteMapStep
• BizTalkSteps/ExecuteReceivePipelineStep
• BizTalkSteps/ExecuteSendPipelineStep

The Pipeline steps use Tomas Restrepo’s Pipeline Testing Library.

I had originally planned on incorporating Bram’s steps into Extensions as I wrote previously.  However after discussing with Kevin, those plans changed so its now in the core BizUnit.

There is a similar MapExecutingStep in Extensions that has been around for a while now and when I get some time I’ll take a closer look at Bram’s step and see if there are any differences that are worth keeping or retire the Extensions step if not required anymore. I have had a couple of bugs reported on Extensions beta-1 which I shall fix soon and get the RTM released which will be compiled against BizUnit 3.1.

BizUnitExtensions_v3.0 Beta-1

Finally made some progress on BizUnitExtensions and have released Beta-1 for the new version which now complies with BizUnit 3.0′s object model. This release specifically centres around the main Extensions and the Extensions.BizTalk  libraries.

Main changes

• The Altova library has now been deprecated as there is much better xml validation support in the .NET Framework so the altova library is redundant.
• The steps for manipulating applications, receive locations and send ports have now been completely overhauled, so there is a separate ApplicationConductorStep, ApplicationGetStatusStep and ApplicationVerifyStatus step and likewise for ReceiveLocations and Send Ports. The GetStatus steps will load the current status into the context which can be useful when we need to use that info in subsequent steps. VerfyStatus will check the status against a given value.
• The ReceivePortConductorEx step in the old code-base has been transitioned to the above mentioned set of ReceiveLocation steps as it really was dealing with locations rather than the ports. There is a new ReceivePortConductor step which allows the bulk enabling and disabling of all the locations in that port.
• Updates to the Orchestration Conductor allowing a STOP action on an orchestration.
• The namespaces and assembly names have all been revised (for example, using the Biztalk steps requires the assembly name to be BizUnit.Extensions.BizTalk.dll) so your existing test cases will need to be updated.

Forthcoming Updates and Releases

• Bram Veldhoen has contributed a fair amount of code including steps to link in with the Pipeline Testing Library. I will incorporate that into Beta-2 as I need to work through all the steps and the associated helpers and utility classes.
• I have updated the Oracle and EntLib libraries as well, but haven’t had any time to test them. As I now have Oracle XE, I should be able to make some progress on that pretty soon. With EntLib, its a little more complicated. As I didnt write those steps myself, I am not too familiar with the code, so it will take a while to update. So for the present, its still using EntLib 3.1. 

Workspace Updates

• The codeplex workspace has also been cleaned up and slimmed down drastically. A lot of the pointers to tutorials etc are all largely redundant anyway.
• The Roadmap page has been completely rewritten. The framework has come a long way since that material was written. The only stuff left there is a list of probable new steps and some ideas for tooling around BizUnit which may make it into some future version of the framework.

Hope you find the updates useful. Let me know if you encounter any bugs or if you have any suggestions.

MockingBird- Beta 2

MockingBird – Beta 2 is now available.

The changes/ fixes are as follows
(1) The system can handle remote WSDL’s now (using DiscoveryClientProtocol). [But this will use the Default network credentials to get the WSDL. There are no facilities as yet for providing this information as settings for the tool).
(2) Fixed the WSDL Browser which crashed when loading WSDLs into the tree view where there were one way operations in the WSDL.
(3) Xml Instance Generator now allows an overloaded constructor where a GeneratorSettings instance can be passed in to control the output.
(4) Documentation has now been split into a User Guide and Technical Documentation and thoroughly revised.

As mentioned in previous posts, the system is very stable (at least for the WSDLs and services I have tested and used it with) , so the fact that it is still officially a beta-2 shouldnt prevent anyone from using it.

Things that need to be done for RTM are

• some additional entry points into the XmlInstanceGenerator,
• adding some “settings” forms where users can set things such as network credentials when dealing with remote WSDLs etc.
• Update the class library documentation
• Use Unity in the Service Studio
• Run the code-base through StyleCop and FxCop. (This last part has me worried . How much am I going to need to rewrite?))

Check it out and, as always, feel free to send feedback.

MockingBird – Beta

Whew! I’ve finally managed to get the first beta release of MockingBird out the door, almost 3 months after the alpha. The past 3 months have gone by in a blur with my first major project in MCS and the associated tight deadlines and long hours. Technically its been a good learning experience, but it doesnt leave any time at all for side projects like this one, but I’ve managed to steal the odd weekend here and there and get this done.

The key elements of the beta release are

• The branding and naming is now beginning to work out quite well. As I had written earlier, it started life as MockWeb, then became MockingBird and now I have decided that I like the name “MockingBird” so much its worth promoting to the ‘brand’ or the name of the toolset. The constituent applications now have their own names. The web application with the HttpHandler is now called the “Service Simulator” and the main WinForms application is now called the “Service Studio” which will hold many modules and plugins.
• The Service Simulator has been completely revised using Unity IoC. I feel a lot happier with the design now and i think its more loosely coupled and the DI /IoC has a good side effect in increasing the test surface. The Service Studio doesnt use the Unity configuration yet, but will do so by RTM.
• The little ‘Driver’ GUI of the alpha has now been rolled into the “Service Studio” and is officially called the “Service Invoker”. The layout has changed and now uses tabs so occupies less screen real estate.
• There is a new “WSDL Browser” module in the service studio that allows you to load up a WSDL and it will parse the WSDL for you and list all the operations and allow you to generate sample request and response messages.
• The WSDL  Browser in turn makes use of an Xml Instance Generator module that provides a more usable facade over a sample from the MSDN archives. The XIG module can stand on its own and will grow in future releases.

The design principle of the Service Studio is that every piece of functionality must be accessible independently and not depend on a UI. This is one of the reasons it took so long to get this done. I came across quite a few samples of WSDL handling where the authors were willing to share and/or the license permitted extension, but the code was simply too deeply hooked into the UI and did not have any “API” to speak of. In the end I wrote the whole thing myself. I’m still looking for ways to plug it into related tools such as WSCF which I also participate in developing.

There are some limitations in the beta especially with regard to WSDL Parsing.

• The first limitation is that it cannot handle WCF multi-part WSDLs. This will be done by around RTM time or along with the V2 release as V2 should be fully WCF based.
• While developing i tested it with different types of WSDLs but in the final push I focussed on testing it with a local monolithic WSDL and so it may fall over with complex WSDL documents. The WSDL spec allows for a wide variation in the actual WSDLs so its not possible for me to cater to all possible kinds of WSDLs. I hope that if you come across an issue, then the source is easy to fix or that you can share the WSDL with me and I will try and sort out the parsing.
• I also only finalised the testing with a “local” WSDL on the file system. The “SimpleWSDLRetriever” class that I have implemented does not use DiscoveryClientProtocol (although i shall plug in a new class soon that does this) so it cant handle connecting to a non local service and downloading the contract and associated metadata. (As you can see, I know how to address the limitation – just havent had the time to write it   ).

Anyway, those limitations aside, I’m happy with the code base so far and it really is quite stable and if you need to extend and use the source, i think the current structure is easy to understand. On the codeplex space I have written more documentation on how the internals of the system work so hopefully that will be useful to you. If you do end up extending it, I hope you will let me know what you are doing with it and maybe I can incorporate some of those extensions if it will make the product more generic.

As always, please send me feedback, especially if you run into any bugs. Hope you like the new release.

BizTalk Testing and Mocks

In an earlier article , I had briefly mentioned that some folk had used mocks with Biztalk, notably to test pipeline components. Since I didnt have the bookmarks at hand then I didn’t provide the links, but I have since found the links again so here they are (and I can also now use this as a note to self if I want to refer to them again or expand on any of the material they have written).

• Testing Pipeline Components – The Pipeline Testing Library – Nick Heppleston
• Unit Testing Pipeline components with Mocks - Rido
• BizTalk Testing Series – Testing Pipeline Components – Mike Stephenson
• TDD and BizTalk Orchestration Expression Code – Matt Podwysocki
• Rhino Mocks and custom BizTalk code revisited   – Matt Podwysocki
• Biztalk TDD – Pipeline Components - Arun Gopalam

While the  blog posts pointing to the Pipeline Testing Library are useful, if you want to go straight to the source, check out the WIKI page that Tomas has set up on GitHub. That page has more samples on how to use the API.

I’m going to have a play around with MoQ and pipeline components in the next couple of days . I think MoQ’s approach is a bit more elegant than Rhino (particularly, the absence of record and replay). I’m also going to link into Tomas’s excellent pipeline testing library from BizUnitExtensions. This has been a long overdue item on my roadmap.

UPDATE: Bram Veldhoen has already done some work on linking the Pipeline Testing Library into BizUnit and has very graciously contributed his code to be put into BizUnitExtensions so that will be released soon with Extensions 3.0.

Enjoy the links and if you find others of a similar ilk that are also useful feel free to put them in the feedback section here and I will update the post.

VS2008 – Generate XML Instances

It’s funny how we take things for granted. As Biztalk developers, we get used to the idea of being able to right click on a schema and generate an instance . In non Biztalk projects however, this couldnt be done. Till now.

I was playing around with writing some XML Instance Generation for MockingBird to finish off the next release and spent a lot of time poking around the Schema Object Model etc. While doing that, I quite accidentally opened the XML Schema Explorer tool window. Now I had seen that in the past and navigated through some types etc (and thinking it was just a simple add-on to the old VS i kind of took it for granted and didnt investigate further). 

What I did not realize is that for Elements, you can generate sample instances.  Check out the following screenshot.

Generate Sample XML

As you can see from the tree behind the popup window, elements are colored differently as well.

This is a great time-saver. I think this can be done only in VS2008 SP1.

Unfortunately, the downside is that there is no API into this tool-window (or rather, the library behind it), so we cannot programmatically generate instances in bulk. Also it will not open WSDL files, so you have to extract the XSD from the WSDL (if not already available separately) in order to work with this tool window. But i think its cool as we no longer have to depend on third party XML editors to get sample instances.

By the way, if you are looking for help in this area (of instance generation) , there is some sample code available in the MSDN article, Generating XML Documents from Schemas which is quite well written. While there are license restrictions on modification/ derivation (and then redistribution), plain redistribution without modification, I gather, is permitted, so the easiest thing for MockingBird would be to just redistribute the binaries of that sample with the GUI. No sense in reinventing the wheel.

In terms of the Biztalk Schema Editor and its instance generation, if any Biztalk folks know if there’s a programmatic way of doing that, please let me know  (Update: I mean specifically for 2006 and R2). I did a lot of digging around in the Developer Tools folder for an assembly that would allow it, but all the classes were internal. I did come across one public class finally (dont remember the assembly off the top of my head now), which had a public method but required some interface to be passed in but didnt work when i tried calling it from custom code. It would be useful to do this programmatically so we can generate instances in bulk for  a given set of schemas (useful when updating instances to correspond to schema changes etc). So, if you’ve managed to do this and are happy to share info then drop me a line.

Introducing ‘Mockingbird’

In my previous post, I briefly mentioned a tool that helped with the testing of web-service consumers. I’m happy to announce that this is now publicly available on CodePlex under the moniker “MockingBird’. Here are some details about the tool – where it came from, how it helps and where it is going. (Most of this info is on the CodePlex space, but i’ll reproduce it anyway).

The Scenarios for MockingBird

(1) Imagine you are given the WSDL for a third-party web-service but no functioning system is available yet (it may be a brand new service or perhaps dev/site licenses are being negotiated). You need to get on with development right now. What do you code against? You maybe a ‘TDD & Mock Objects’ savvy dev which will help in many cases, but what if you ‘don’t do’ TDD & Mocks? Or it may be that you are maintaining/enhancing an existing system that wasn’t coded against interfaces etc. Or what if you are a BizTalk developer? You cannot mock/inject dependencies into your orchestrations and other components (well, except for pipeline components, but thats another story)!!

(2) Next, imagine that you are setting up a build server and multiple environments (DEV, TEST, UAT etc). But now the vendor says you can only have one license for their software. Now how do you run DEV, TEST, UAT in parallel with different data sets? Or you may have more than one license, but what if that service has maintenance schedules that clash with your build? Your build server is then completely exposed to something you don’t control.

I’ve expanded on these scenarios in the tool documentation here, but essentially these are the two main scenarios that MockingBird targets.

The Origins of MockingBird

MockingBird started life as MockWeb an internal tool that my former colleagues (Senthil Sai and Will Struthers) and I developed. All credit must go to them as Senthil first came up with the concept and Will then contributed a lot to the code-base.

It started when we got rather fed up with having to set up multiple instances of a third party service and build data-sets just to help with testing our BizTalk orchestrations reliably. It grew rapidly and organically. While we felt that this concept and tool would be useful to the .NET dev community at large (not just BizTalk teams), the structure of the codebase (at the time) would not lend itself to easy extension and needed to be refactored before making it publicly available. Its taken a while , but now I’ve completely rewritten MockWeb and as I have mentioned in the roadmap, I intend this to go beyond HTTP Web Services and hence the new name.

Whats with the name – ‘MockingBird’ ? Sounds daft !!

Ok, so its not a tool that sits there and laughs at you when you try to test !! . Thats not what the name is intended to convey. Wikipedia says that “They (mockingbirds) are best known for the habit of some species mimicking the songs of insect and amphibian sounds as well as other bird songs,[1] often loudly and in rapid succession” .

So the intent is to mimic web-services and I quite like the name ‘MockingBird anyway!!

The current implementation

There are two main elements to the current implementation

• An ASP.NET HttpHandler which is configured to return pre-set responses
• A WinForms GUI to setup the handler and associated configuration for a given WSDL.

The Roadmap

• The first thing I intend to do is revise the implementation to be fully WCF based as i want to be able to intercept calls irrespective of transport protocol. This is 0ne of the reasons i rewrote the code-base and i hope there wont be too much churn as i extend it
• The second thing is to make it a sort of platform to test webservices, generate BizUnit test steps, maybe C# test fixtures, possibly to code-gen Biztalk artifacts from given WSDLs and schemas.
• Thirdly to take it into the realm of mock Biztalk adapters. WCF is key to that. I envisage this as being a pair of custom WCF send and receive adapters that can dynamically be configured.
• Beyond that, lets see .

So, check it out. There’s an alpha release currently available and your feedback will be appreciated. If you have any thoughts on how the mock Biztalk adapters could be done, I will be glad to hear and of course, if you want to join the project, you will be welcome.