As a developer it’s important to reduce the number of errors or create performant applications; but when errors do happen its become even more important to be able to identify issues or trace the calls. This would make you efficient and identify bottlenecks quickly. Fiddler is one such tool, and understanding workflow of Fiddler would be critical to ensure traffic flows can be understood and necessary modifications can be done to request or response.
Fiddler Workflow (Functionally explained)
Fiddler has two flows (request flow and response flow).
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Fiddler workflow
If intent for you is to intercept the request from user before hitting the server to transform the content or log the request, you will be needing to create logic on request flow.
Request flow has mainly 3 components
OnPeekAtRequestHeaders: Fiddler first receives the request headers, before the body is processed from user. you can only log, add or transform response header values
OnBeforeRequest: Fiddler receives the complete request from user, and content transformations on the request including body can be done before sent to server.
OnAfterRequest: Fiddler has already sent the request to the server, so no changes can be done on the request. This…
