A few months ago we at Tellago had open sourced
the BizTalk Data Services. We were meanwhile working on other artifacts which comes along with BizTalk Server like
the “Business Rules Engine”. We are happy
to announce
the first version of BRE Data Services. BRE Data Services is a same concept which we covered through BTS Data Services, providing a RESTFul OData – based API
to interact with
the Business Rules Engine via HTTP using ATOM Publishing Protocol or JSON as
the encoding mechanism.
In
the first version release, we mainly focused on
the browsing, querying and searching BRE artifacts via a RESTFul interface. Also along with that we provide
the functionality
to execute Business Rules by inserting
the Facts for policies via
the IUpdatable implementation of WCF Data Services.
The BRE Data Services API provides a lightweight interface for managing Business Rules Engine artifacts such as Policies, Rules, Vocabularies, Conditions, Actions, Facts etc.
The following are some examples which details some of
the available features in
the current version of
the API.
Basic Querying:
Querying BRE Policies
http://localhost/BREDataServices/BREMananagementService.svc/Policies
Querying BRE Rules
http://localhost/BREDataServices/BREMananagementService.svc/Rules
Querying BRE Vocabularies
http://localhost/BREDataServices/BREMananagementService.svc/Vocabularies
Navigation:
The BRE Data Services API also leverages WCF Data Services
to enable navigation across related different BRE objects.
Querying a specific Policy
http://localhost/BREDataServices/BREMananagementService.svc/Policies(‘PolicyName’)
Querying a specific Rule
http://localhost/BREDataServices/BREMananagementService.svc/Rules(‘RuleName’)
Querying all Rules under a Policy
http://localhost/BREDataServices/BREMananagementService.svc/Policies('PolicyName')/Rules
Querying all Facts under a Policy
http://localhost/BREDataServices/BREMananagementService.svc/Policies('PolicyName')/Facts
Querying all Actions for a specific Rule
http://localhost/BREDataServices/BREMananagementService.svc/Rules('RuleName')/Actions
Querying all Conditions for a specific Rule
http://localhost/BREDataServices/BREMananagementService.svc/Rules('RuleName')/Actions
Querying a specific Vocabulary:
http://localhost/BREDataServices/BREMananagementService.svc/Vocabularies('VocabName')
Implementation:
With
the BRE Data Services, we also provide
the functionality of executing a particular policy via HTTP. There are couple of ways you can do that though
the API.
Ø First is though Service Operations feature of WCF Data Services in which you can execute
the Facts by passing them in
the URL itself. This is a very simple implementations of
the executing
the policies due
to the limitations & restrictions (only primitive types of input parameters which can be passed) currently of
the Service Operations of
the WCF Data Services. Below is a code sample.
Below is a traced Request/Response message.
Ø Second is through
the IUpdatable Interface of WCF Data Services. In this method, you can first query
the rule which you want
to execute and then inserts Facts for that particular Rules and finally when you perform
the SaveChanges() call for
the IUpdatable Interface API, it executes
the policy with
the facts which you inserted at runtime. Below is a sample of client side code. Due
to the limitations of current version of WCF Data Services where there is no way you can return
back the updates happening on
the service side
back to the client via
the SaveChanges() method. Here we are executing
the rule passing a serialized XML as Facts and there is no changes made
to any data where we can query
back to fetch
the changes. This is overcome though
the first way
to executing
the policies which is by executing it as a Service Operation call.
This actually generates a AtomPub message shown as below:
POST /Tellago.BRE.REST.ServiceHost/BREMananagementService.svc/$batch HTTP/1.1
User-Agent: Microsoft ADO.NET Data Services
DataServiceVersion: 1.0;NetFx
MaxDataServiceVersion: 2.0;NetFx
Accept: application/atom+xml,application/xml
Accept-Charset: UTF-8
Content-Type: multipart/mixed; boundary=batch_6b9a5ced-5ecb-4585-940a-9d5e704c28c7
Host: localhost:8080
Content-Length: 1481
Expect: 100-continue
--batch_6b9a5ced-5ecb-4585-940a-9d5e704c28c7
Content-Type: multipart/mixed; boundary=changeset_184a8c59-a714-4ba9-bb3d-889a88fe24bf
--changeset_184a8c59-a714-4ba9-bb3d-889a88fe24bf
Content-Type: application/http
Content-Transfer-Encoding: binary
MERGE http://localhost:8080/Tellago.BRE.REST.ServiceHost/BREMananagementService.svc/Facts('TestPolicy') HTTP/1.1
Content-ID: 4
Content-Type: application/atom+xml;type=entry
Content-Length: 927
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<entry xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" font-size: x-small"http://www.w3.org/2005/Atom">
<category scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" term="Tellago.BRE.REST.Resources.Fact" />
<title />
<author>
<name />
</author>
<updated>2011-01-31T20:09:15.0023982Z</updated>
<id>http://localhost:8080/Tellago.BRE.REST.ServiceHost/BREMananagementService.svc/Facts('TestPolicy')</id>
<content type="application/xml">
<m:properties>
<d:FactInstance><ns0:LoanStatus xmlns:ns0="http://tellago.com"><Age>10</Age><Status>true</Status></ns0:LoanStatus></d:FactInstance>
<d:FactType>TestSchema</d:FactType>
<d:ID>TestPolicy</d:ID>
</m:properties>
</content>
</entry>
--changeset_184a8c59-a714-4ba9-bb3d-889a88fe24bf--
--batch_6b9a5ced-5ecb-4585-940a-9d5e704c28c7—
Installation:
The installation of
the BRE Data Services is pretty straight forward.
· Create a new IIS website say BREDataServices.
· Download
the SourceCode from TellagoCodeplex and copy
the content from Tellago.BRE.REST.ServiceHost
to the physical location of
the above created website.
·
The appPool account running
the website should have admin access
to the BizTalkRuleEngineDb database.
· TheRight click
the BREManagementService.svc in
the IIS ContentView for
the website and wala..
Conclusion:
The BRE Data Services API is an experiment intended
to bring
the capabilities of RESTful/OData based services
to the Traditional BTS/BRE Solutions.
The future releases will target on technologies like BAM, ESB Toolkit.
This version has been tested with various version of BizTalk Server and we have uploaded
the source code
to our Tellago's DevLabs workspace at Codeplex. I hope you guys enjoy this release.
Keep an eye on our new releases @ Tellago Codeplex. We are working on various other Biztalk Artifacts like BAM, ESB Toolkit.
Till than happy BizzRuling…!!!
Thanks,
Vishal Mody
