Mohammed Atef’s Technical blog

AS/400 BizTalk Adapters

Introduction
Microsoft® BizTalk® Server has providing a suite of new technology adapters. These include a new set of adapters for IBM Host Integration scenarios covering DB2, WebSphere MQ, Host Applications, and Host Files. In this post we shall look at WebSphere MQ and Host Files adapters in detail and explain their capabilities and use with AS/400.

WebSphere MQ Adapters
Now WebSphere MQ server on Windows is no longer required to connect to remote Queue Managers on non-Windows® systems. With the Server adapter a component is installed on the MQ computer that interacts with the MQ APIs.Let see MQ adapter architecture with BizTalk in the below image
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The above image shows two environments are depicted, the BizTalk Server on Windows Server and an MQ Server which is running on AS/400. The MQSC adapter which enables sends and receives functionality using the chosen client. The MQ architecture for the Client works by receiving and sending messages to and from queues using a channel. A channel is a uni or bi-directional securable mechanism to perform reliable communication and is defined on a given Queue Manager on the server. Between the Client and the Queue Manager on both ends is the Message Channel Agent. It is the agent’s responsibility to control the send and receipt of messages.
Essentially there are three main components to using the Client adapter: MQ Client configuration, BizTalk Server port configuration, and the solution design itself. Let’s cover each of these in turn.

Client Configuration
MQ Client Configuration starts with a choice between the Base Client and Extended Client . The principle difference between the two is that the Extended Client is fully transactional while the Base Client is not. However, the BizTalk Server adapter is still able to guarantee at least once delivery with the Base Client due to the way it uses the client. Essentially, the adapter first retrieves a batch of messages non-destructively and only once they are safely in the MessageBox database are they removed from the queue. This is achieved using a cursor in MQ to enable locking and browsing of a queue without removing the messages. The same process occurs in reverse when sending messages, where the adapter checks the messages are safely on the queue before responding to the BizTalk Message Agent , which will then remove them from the MessageBox database. Because of this, it is possible in failure conditions to cause duplicate messages to be processed and your solution must take this into account if necessary. The Extended client ensures “once and once only” semantics.

BizTalk Server Configuration

There are a multitude of options here and we will consider the use of the most important ones here. The first thing to mention is that configuration is handled differently on Send and Receive. On the Receive side, the transport configuration is achieved through creating a Receive Location while on the Send side a Send Port is created and configured as shown below.
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First, the connection between the BizTalk Server and the MQ Server must be defined. This is covered by four properties: channel name, connection name, queue and queue manager name.
The MQ adapter supports full ordered delivery on both the receive and send sides. When both are configured, First In, First Out (FIFO) processing all the way through BizTalk Server is possible .
Now let’s see how the orchestration is implemented as found in the below image
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The above image shows an orchestration using the MQ client adapter and manual correlation to implement a solicit-response pattern. First, the orchestration must set the MQ header MQMD_CorrelID to a unique ID and a correlation set initialized containing this context property. Next, the message is sent to an MQ queue. After a period of time, a second message is received on a different queue. The adapter automatically copies this property and the receive port has a following correlation set – the same as that initialized in the send port. This ensures the second message is correlated to the first and the response message delivered to the correct orchestration. Using this approach, two different queues can be used to implement a more flexible approach to the solicit-response pattern.

for BizTalk Adapter for host files you can find this in this post

I hope this help.

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June 24, 2009 Posted by | Biztalk | , , , | 2 Comments

BizTalk Adapter for Host Files

This adapter, as its name suggests, enables access to files in a host environment. The Host File adapter enables full CRUD (Create, Read, Update & Delete) access using a SQL-like syntax, implemented in a new managed provider. When used stand-alone the provider enables SQL to be used to provide a familiar ADO.NET programming model for data access. The adapter’s supports usage on both send and receive Ports.

Defining File Structures

There are two constituents to creating a BizTalk solution using the Host File adapter. The first is specific to the host file adapter, a file definition, and the second is the familiar schema generation discussed above in the context of the DB2 adapter. A schema is required to define the file data sent back and forth using XML whilst the file definition is needed to map the file’s contents to XML. Figure below shows this relationship in detail. Taking a look at the file definition first, Host Integration Server introduces a new Microsoft Visual Studio® project type, Host File, enabling the creation of host file definitions. A definition can be created in several ways; manually, through program import or from an existing Host Column Definition (HCD) file.

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By selected “Add Generated Items” and the File Adapter we can now create the schema to use for transferring data between BizTalk Server and the Host. There are three options, updategrams, SQL SELECT or OS/400 Command. The SQL SELECT option allows the host file system to be queried using a SQL-like syntax. An example select contact,title from customer.

Configuring Ports

Once both the schema and metadata file assembly have been created a port can be configured. As already mentioned, the adapter supports both Send and Receive ports allowing File Polling Receive-side and one-way or solicit-response Send-side. Figure below shows the Receive Location property page for the File Adapter. The connection string can be provided manually or through the Data Source Wizard as with DB2. There are some additional options for host files, the principle one being the Metadata property, which contains the name of the metadata assembly containing the file definition.
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Host File adapter does not support batching and returns only a single message for all data returned from a file in one operation. If single record/message processing is required, an envelope schema can be used to split the message up in the receive pipeline processing. This technique may be used whether a Receive Location or solicit-response Send port is being used to return data. The splitting of messages enables parallelism to be achieved allowing BizTalk Server to process multiple records simultaneously rather than having to de-batch them in an orchestration.
The Root element name/namespace are required to create the response messages from the adapter. The purpose of this is to ensure the incoming message (generated by the adapter) will match a particular schema. The SQL Command property enables a SQL query to be specified . Update Command allows the retrieved records to be updated or deleted as required. The principle use for this is to ensure that the same data is not picked up twice due to the polling nature of the adapter. If update is specified, the values for each field to update on each retrieved record must be specified. The URI property value specified must be unique.
Send side, Figure below shows the options. As you can see the configuration is much simpler, with only the connection string and document namespace/root name required with the unique URI. This is because all the information required for accessing the host file is provided in the message schema. It is to this configuration that we turn next.

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Although the BizTalk Adapter for Host Files provides a great deal of functionality to process file data through BizTalk Server, there are a couple of limitations that you should be aware of. Firstly, the adapter is not transactional with respect to the Host File system. Although the Host will ensure failure cannot corrupt the file being updated, updates may be lost.
The second limitation is that the adapter does not support dynamic sends. A dynamic send is where the URI containing transport and endpoint address is specified at runtime. The adapter only enables the URI details to be specified on a static Send Port and BizTalk Server will not allow the adapter to be selected on Send Ports defined as dynamic in an orchestration.
I am going to prepare sample for host files adapters with BizTalk in few days.

I hope this help.

June 24, 2009 Posted by | Biztalk | , , | 1 Comment