Azure API Management: CORS guide with Preflight Requests in OpenAPI Definitions
I'm currently integrating Azure API Management with a service that returns an OpenAPI definition, and I'm working with issues with CORS when making requests from my frontend application... Specifically, I'm receiving the following behavior in the browser console: `Access to fetch at 'https://<api-url>' from origin 'https://<frontend-url>' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.` I've already added CORS settings in the API Management service, but it seems like preflight requests are not being handled properly. Here’s the configuration I am using to enable CORS within the Azure portal for my API: ```json { "methods": ["GET", "POST", "OPTIONS"], "origins": ["https://<frontend-url>"], "headers": ["Content-Type", "Authorization"], "exposeHeaders": [], "maxAge": 3600 } ``` Despite this, when I check the network tab, the preflight OPTIONS request is returning a `403 Forbidden` status. I also tried adding the `access-control-allow-origin` header directly in the backend service response, but that didn't resolve the scenario. My API is deployed in Azure using the latest version of Azure API Management, and the backend is an Azure Function. I've also verified that the function is accessible and correctly configured. Has anyone else faced this scenario, or can anyone suggest additional steps to troubleshoot this CORS question with API Management? My development environment is Linux. I'd love to hear your thoughts on this. I'm working on a web app that needs to handle this. Is there a better approach?