Migrating BizTalk Transformation To Azure using Azure Function as an API

In this article, I would brief about Migrating BizTalk Transformation As-Is to Azure Function(API) and this can be invoked from Logic App. Thus the transformation can be execute across different resource group, region and integration account.

Using Azure SDK, I have create a simple HTTP Trigger function. This has two projects, TrasformationHelper(TransformAPI) and AzureFunctionHelper.

In TransformAPI, we extract the request body and map name from the query string and invoke utility helper for the transformation.

In AzureFunctionHelper, I have embedded the XSLT and Extension Objects as resource files and based on the MapName, we would dynamically execute the transformation and render the transformed result as HTTP Response to client.

Here is the XSLT for one of the transformation and this invoke external assembly methods, as shown. External assembly method does DB Lookup. Lets add the reference of External Assembly to Azure Function Project.

Lets configure hybrid connection in Azure Function. select Networking and click on configure your hybrid connection endpoints. Click on Add hybrid Connection, 
Create a new or bind to existing Hybrid Connection. Refer my earlier article for configuring azure hybrid connection to access on-prem sql server.

Lets deploy and test the Azure function API. This can be invoked from Logic App to achieve dynamic transformation.

Note:- External Assembly would be package as part of Azure Function Package. This allows us to completely re-use BizTalk Transformation as-is.

Logic App | Integrating with Azure Function

In this article, I will integrate Azure Generic Webhook function with Logic App.

Lets create a generic webhook function and generate a code from json request as shown and use it the function.

This function validates the JSON input and renders response based on the unit provided.

Lets create Logic App and choose a blank template,as shown below.

 Bring in a HTTP Request,

 Using Sample JSON, we can generate the JSON schema and the configure the HTTP verb as post and provide the relative path

Once HTTP request is configured, we can add a new step and then choose an action and configure the Azure Function. Then pass in the HTTP body to function as shown.

Now, we can validate the response using condition and control the flow for true and false path.

Save the logic app and push message using PostMan tool and validate the behavior