Azure Function to Apply XML Validation (Advanced)

Azure Function to Apply XML Validation (Advanced)

After the release of our previous XML Validation Functions: 

It is now time to release our last Azure Function under the same context: an Azure Function to Apply XML Validation (Advanced).

As I explained in my previous posts, all the out-of-the-box Azure Integration Services capabilities to validate XMLs have a huge limitation: they don’t allow us to have a chain of XML Schemas! As I also mentioned, this is a common feature present in many Enterprise XML Schemas definitions. EDI or RosettaNet Schemas may have 2 or more schemas that define the overall structures of the messages. Blocking this way many enterprise scenarios that we need to address in our Azure integration solutions.

Our previous Azure Function allows us to solve many of those scenarios, and it can be used inside Logic Apps Consumption or Standard or even inside API Management. However, it also has a limitation: it only allows first-level chain support for XML Schemas (meaning that it will only take into consideration all the import schemas of the main XML Schema).

However, for example, in RosettaNet Schemas, it is very common that our main schema imports a “child” XML Schema and that child schema imports or includes other XML Schemas itself.

Apply XML Validation (Advanced)

What does this Azure Function do?

This Azure Function allows you to perform XML validations against an XML Schema, including support for all chains of XML Schemas. That means that it will take into consideration all depth of importation for a specific type of message. It will recursively include or import all XML Schemas, supporting this way all types of XML message validation.

To trigger this function, you need to:

  • In the Body, the XML payload that you want to be validated.
  • You should specify the following mandatory headers:
    • Content-Type as text/xml (or application/xml).
    • SchemaFileName with the name of the XML Schema (XSD) file present in the storage account.

The response will be a:

  • 200 OK – Validation successful. If it’s a valid message.
  • Or 400 Bad Request with a list of errors if there is something invalid.

Notice that by default, if you send a message to be validated against a schema that doesn’t have the same target namespace and root node, the response will be an OK. This function also validates that type of message, so if you send a message that doesn’t correspond to that schema, you will get a 400 Bad Request.

Where can I download it?

You can download the complete Azure Functions source code here:

Hope you find this helpful! So, if you liked the content or found it useful and want to help me write more, you can buy (or help me buy) my son a Star Wars Lego! 

Thanks to my team member Luís Rigueira for helping me realize and implement this idea.

Author: Sandro Pereira

Sandro Pereira lives in Portugal and works as a consultant at DevScope. In the past years, he has been working on implementing Integration scenarios both on-premises and cloud for various clients, each with different scenarios from a technical point of view, size, and criticality, using Microsoft Azure, Microsoft BizTalk Server and different technologies like AS2, EDI, RosettaNet, SAP, TIBCO etc.

He is a regular blogger, international speaker, and technical reviewer of several BizTalk books all focused on Integration. He is also the author of the book “BizTalk Mapping Patterns & Best Practices”. He has been awarded MVP since 2011 for his contributions to the integration community.
View all posts by Sandro Pereira