Issue with Azure Flask Webhook Deployment for traneasy.com.cn – HTTPS Endpoint Not Receiving External POST Requests

Question

Hello Azure community,

I’m currently working on integrating external service callbacks into our website http://traneasy.com.cn/. The backend is built with Python (Flask), and we are deploying the webhook endpoint on Azure to receive event payloads (HTTP POST requests) from a third-party API service.

While the application logic works correctly in local development (tested via tools like ngrok), I’m encountering issues after deployment to Azure. The webhook provider requires a publicly accessible HTTPS endpoint. However, after deploying to Azure (both via Azure Functions and Azure Web App), the external service is unable to successfully deliver webhook payloads to the defined Flask route.

Current Setup

Backend: Python + Flask

Hosting attempts:

Azure Web App (Linux, Python runtime)

  Azure Function (HTTP trigger)
  
  Endpoint format example:
  

https://traneasy.azurewebsites.net/api/webhook

The Flask route is defined to handle POST requests and parse JSON payloads.

Observed Issues

The endpoint is reachable via browser (GET returns expected response).

When the third-party service sends a POST request:

Either no request reaches the application (no logs triggered), or

  The service reports timeout / unreachable endpoint.
  
  HTTPS is enabled by default on Azure, but I’m unsure whether:
  
     Additional configuration is required (CORS, inbound rules, App Service authentication, etc.).
     
        TLS validation or certificate binding is interfering.
        
           There are networking constraints (e.g., Azure firewall, VNet settings).
           

Questions

Is Azure Web App sufficient for receiving external webhook POST requests without additional networking configuration?

Are there specific settings required in Azure (e.g., disabling authentication, configuring inbound IP restrictions, Always On, SCM settings)?

For Flask apps deployed via Azure Web App, are there recommended best practices for webhook reliability (timeouts, gunicorn config, ARR affinity, etc.)?

Would Azure Functions (HTTP trigger) be more appropriate for this use case?

I would appreciate guidance from anyone who has successfully deployed a Flask-based webhook receiver on Azure and handled external event payloads reliably.

The Flask route is defined to handle POST requests and parse JSON payloads.

Observed Issues

The endpoint is reachable via browser (GET returns expected response).

When the third-party service sends a POST request:

Either no request reaches the application (no logs triggered), or

  The service reports timeout / unreachable endpoint.
  
  HTTPS is enabled by default on Azure, but I’m unsure whether:
  
     Additional configuration is required (CORS, inbound rules, App Service authentication, etc.).
     
        TLS validation or certificate binding is interfering.
        
           There are networking constraints (e.g., Azure firewall, VNet settings).
           

Questions

Is Azure Web App sufficient for receiving external webhook POST requests without additional networking configuration?

Are there specific settings required in Azure (e.g., disabling authentication, configuring inbound IP restrictions, Always On, SCM settings)?

For Flask apps deployed via Azure Web App, are there recommended best practices for webhook reliability (timeouts, gunicorn config, ARR affinity, etc.)?

Would Azure Functions (HTTP trigger) be more appropriate for this use case?

I would appreciate guidance from anyone who has successfully deployed a Flask-based webhook receiver on Azure and handled external event payloads reliably.