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New Post: Load predefined items in pulldown in Activity Property page

tfierens — Tue, 17 Feb 2009 00:49:49 GMT

Hi,

I was wondering if anyone had any ideas on the following. I want to read an xml file which will contain specific values that I want to load and display as a pull-down for a property for a custom activity. In other words, imagine I have a property called DocumentType, and my xml contained the following values Invoice, Credit Note and Statement. I want to display a property called DocumentType in the Property Page when in the IDE which will be represented by a pull-down which in turn will list my various options.

Any ideas? Even better, do you have a sample code?

Much appreciated.

Regards,

T.

NEW POST: Fault handling with WCF activities

vriesmarcel — Wed, 05 Sep 2007 18:33:12 GMT

Duncanjs,
Fisrt of all sorry for this very late reply. I always forget to check the discussion list and I don't reciev mail when something is posted :-(

In the case of authorization the best way to do this is probably just using the WCF AuthoriationService class that you can implement yourself and add that to the service configuration. this way tthe message is never dispatched to the WCF stack in the workflow and therefore you will not be bothered with terminated workflows if you would throw an exception.

I do agree that a fault activity might be a nice thing to look into, I never needed it myself because I always use the service implemetnation pattern Message in - Messgae out where the out message contains the information that authorization failed. So I handle the exceptions in the code and return the information in the return message, not using Soap Faults.

If I can find some time I will see if I can create such a Fault activity as well.
thanks for the feedback,
Marcel

NEW POST: Loading workflow from a XOML file

Codeman1980 — Tue, 19 Jun 2007 10:05:16 GMT

Hi!

How can I load a XOML workflow from the filesystem/database when I use your WCF activities?
As far as I have seen the whole WCF hosting code is autogenerated...

Thanks

Klaus Aschenbrenner
http://www.csharp.at
http://www.csharp.at/blog

NEW POST: Fault handling with WCF activities

duncanjs — Sat, 16 Jun 2007 07:40:17 GMT

Hi Marcel,

Thank you for providing this code! I've been struggling with some limitations with asmx web services in general but could not look at WCF because workflow activities for this are still some time away from Microsoft.

One big difference I notice with your activities as appose to the asmx ones are you have no WebServiceFault equivalent? I have been struggling to understand how best to handle returning faults without terminating the workflow for example if there was an authorization problem or database constraint violation or the like during the operation between the input and output activities.

How would you suggest handling these situations with your activities?

Regards,
Duncan

NEW POST: Custom SQL work flow service

SonnyM — Thu, 03 May 2007 04:43:15 GMT

Marcel,

Yes your right, querying instance is not the place, and i'm now glade that binary formating is used for serialisation.
Tracking extracts are designed for querying state.

Cheers
Sonny M

ice to have - Configuration settings:

vriesmarcel — Mon, 12 Mar 2007 05:42:15 GMT

You are right. And at this moment the only way to fix this is what you stated and that is to create a custom persistence service that handles the logic.

Custom SQL work flow service:

vriesmarcel — Mon, 12 Mar 2007 05:38:26 GMT

Sonny, You definitly need to look at tracking. Use tracking Extracts to get the data you want and define some tables you feel comfortable with for querying.

Persistency is absolutely not the place for querying running instances.
Regards,
Marcel

ice to have - Configuration settings:

SonnyM — Thu, 01 Mar 2007 22:47:18 GMT

Not sure if this belong in the work flow threads or page flow threads:

Under the page flow custom section within the config file there are work flow service settings.
For example,
<pageFlow>
<pageFlowProvider providerType="Microsoft.Practices.PageFlow.WorkflowFoundation.WorkflowFoundationPageFlowProvider, Microsoft.Practices.PageFlow.WorkflowFoundation"/>
<hostingWorkflowRuntime Name="Hosting">
<Services>
<add type="System.Workflow.Runtime.Hosting.SqlWorkflowPersistenceService, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionString="The actual Connection String details" LoadIntervalSeconds="5" UnloadOnIdle="true"/>
<add type="System.Workflow.Runtime.Hosting.ManualWorkflowSchedulerService, System.Workflow.Runtime, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" useActiveTimers="true"/>
<add type="System.Workflow.Activities.ExternalDataExchangeService, System.Workflow.Activities, Version=3.0.00000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
</Services>
</hostingWorkflowRuntime>
<pageFlowInstanceStoreProvider providerType="Microsoft.Practices.PageFlow.Storage.EnterpriseLibrary.PageFlowInstanceCorrelationSqlProvider, Microsoft.Practices.PageFlow.Storage.EnterpriseLibrary" connectionString="Connection Name that references connection String Section"/>
<pageFlowInstanceCorrelationTokenProvider providerType="Microsoft.Practices.PageFlow.Storage.EnterpriseLibrary.CookiePageFlowCorrelationTokenProvider, Microsoft.Practices.PageFlow.Storage.EnterpriseLibrary"/>
</pageFlow>

The page flow instance provider allows you to just put in the 'connection name' which is used to references the connection string via connection string section. However, under the hosting work flow run time when adding a sql work flow persistence service you can NOT just set a connection name, but need to put the actual connection string within it. It would be nice to just to put in a connection name so that all connection string within the configuration file are centralized within the connection string section.

• A work around is to code a custom persistence service that handles the logic to reference from the connection strings section, but that seems over kill.

Regards
Sonny M

Custom SQL work flow service:

SonnyM — Wed, 28 Feb 2007 11:51:20 GMT

Marcel,

I have a situation where a web workflow has activates associated with quotes, I need away for customer support to query the database to find out what state a person putting in a quote is at. Produce reports using MS reporting service ( no need to create an instance of the work flow.

1) The ‘User Data; property in the work flow contains strongly typed object also serializable, lets say customer data contract (first name last name) used to identify the work flow instance the client is using.

2) Page flow is also used with the work flow in a web environment.
3) I want to have the ability to query the database with out creating an instance of the work flow, Admin pages that just query the work flow database.

• My understanding of tracking is that it contains meta-data about activities and events, no actual data such as user data within the work flow. But, will go back and look into the tracking. The instance is still in binary format.

If I have the ability to query the database, then I can allow customer support to find a specific instance within the work flow and override the instance, take over it and finish the work flow for a customer.

• Hope that makes sense

Regards
Sonny M

Custom SQL work flow service:

vriesmarcel — Wed, 28 Feb 2007 09:48:01 GMT

Sonny,
Can you please describe from what requirement you want to be able to use a different persistence format then binary?

I can't think of a reason why you woul want this. If it is to be able to query status of a workflow from persistence that you need to use the tracking services in stead. It is a common misunderstanding that people want to query the persistence store for status information, but the persistence store is only used for providing workflow robustness.

Also be aware of the fact that persistence data contains more then the activity tree, because it needs also to keep track of work already done so a compensation can be initiated after persistence has occured.

Can you give me an idea of the usecase for what you are trying to chage persistence format?

Thanks,
Marcel

Custom SQL work flow service:

SonnyM — Tue, 27 Feb 2007 22:45:57 GMT

Hi,

I've done some further digging around and come to the following conclusion:

To code a custom persistence service the base class(WorkflowPersistenceService, IPendingWork) needs to be inherited. They have a dependency on the 'Activity' class which also has a dependency on PendingWorkItem class.
the 'pending workItem' class can be described as a container for the serialized work flow object. The property within the class 'public byte[] SerializedActivity;
' that contains the data is byte[] which means we can only use binary formatter :(.

So regardless of the custom state service we write, we are locked into using binary formatter unless we re-code some of the work flow engine and change the db schemes for state table, which makes it a custom solution for the one workflow which is not good.

I'm hoping i my view has a short fall and that someone can explain another option, help much appreciated.

Regards
Sonny M

I’m surprised there is no config attribute to explicitly defined the serialization method just like majority of other .Net providers.

Custom SQL work flow service:

SonnyM — Tue, 27 Feb 2007 01:24:09 GMT

I have a need to serialize work flow activates as XML ‘not’ binary format. so I have gone down the path of a custom sql work flow service which will give me the capability to override methods that serialize and de-serialize. However, I have questions that need answering prior to doing this:

Do I change the underling 'state' table schema within the work flow db schema from binary column to ntext or create a new table and write to it instead.
The second choice seems the most likely but then I need to override more methods across types.

Do I create new db tables or just modify the existing state table.

Direction would be much appreciated.
Cheers
SonnyM
Sonny M