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How to work with Charles proxy server

In this post, I am going to share a technique which will help you in debugging your mobile application code effortlessly even if your server is down.

To set up the Charles server, follow the below steps:
          ·   Install the free Charles software from
·   Open Charles, go to Tools -> Map local
·   In map local window/popup, click add. Add the relevant details like Host, Port(8080), Path, Query of URL.
·   Under "map to" option:- Select the local JSON file
·   Click done and a popup will look like this: (location will have the URL string, the local path will have the path of JSON file)

·   Now go to Tools - Rewrite
·   In the rewrite popup, Select the "Enable rewrite option" and add the previous URL here
·   Add the following rewrite rule

·   Click ok and apply all the settings.
·   Now run the application in simulator and API's response will be read from given local JSON file.

If you are not able to read the data from local json file, then install the certificates from following path:-

1. Reset your simulator
2. In Charles menu, Help > SSL Proxying, and select Install Charles Root Certificate in iOS Simulators
3. Restart your simulator


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