Fiddler AutoResponder for Rapid Development and Debugging

Fiddler is one of the core tools used by any web developer. In my experience, most developers are familiar with the primary feature of showing and interacting with the network traffic between the user and the server. Less often they know about other great features like Composer and AutoResponder.

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The Fiddler AutoResponder feature allows developers to automatically respond to a call on the server, like a request for an image or JavaScript file, with a file on the developer’s local computer. In the above image, I am setting up my AutoResponder to help me quickly develop and debug my “base.js” file that was previously deployed to my Office 365 tenant. (Be sure to check the “Enable automatic responses” box AND check the “Unmatched requests passthrough” box) In this scenario, I am writing an enhancement or debugging an issue with an existing JavaScript file I’ve written and deployed. Instead of spinning up a VM or making changes and uploading files frequently, I can just use Fiddler to respond, for my local browser session only, with that same file. Now I can just make changes locally, hit save, and hit refresh to see what it would look like!

Check out the walkthrough video from Telerik below.

Tim Ferro

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