Calling HTTP Requests Using User Defined Functions in Fabric

[ananthkrishna99]

Hi Team,

Is there a way to make HTTP requests using User Defined Functions (UDFs) in Microsoft Fabric, similar to how we do it in Azure Functions?

We are currently trying to retrieve data from a webhook using a UDF in Fabric. However, when we attempt to add an HttpRequest as an input parameter, we encounter the following error:

Function "webhookTest": input parameter "requ" type must be one of "str, int, float, bool, None, list, dict, set, tuple, datetime, UserDataFunctionContext, FabricSqlConnection, FabricLakehouseClient, FabricLakehouseFilesClient"

Would appreciate any insights or workarounds.

[v-hashadapu · Accepted solution]

Hi @ananthkrishna99 , Thank you for reaching out to the Microsoft Community Forum.

In Microsoft Fabric, User Defined Functions (UDFs) cannot directly make HTTP requests, such as calling a webhook, because they run in a sandboxed environment that restricts parameter types to internal data types like str, dict, or FabricLakehouseClient. This is by design, unlike Azure Functions, which support general-purpose compute and HTTP triggers, Fabric UDFs are optimized for secure, in-platform data transformation. To work around this, you can use a Fabric pipeline with a Web Activity to call the webhook and store the response in a Lakehouse or Delta Table, then process it using a UDF. Alternatively, use a Spark notebook to fetch the data with Python’s requests library and write it to a Fabric table.

For real-time scenarios, use an Azure Function to handle the webhook, then push the result to OneLake or Blob Storage and ingest it into Fabric. UDFs can then operate on the ingested data using supported input types. This architecture maintains Fabric’s security model while enabling external data integration through orchestrated tools like pipelines, notebooks, or serverless compute.

If this helped solve the issue, please consider marking it 'Accept as Solution' so others with similar queries may find it more easily. If not, please share the details, always happy to help.
Thank you.