Another story about fixing bug. This story is related to the native web API fetch, which is used to make request.

Backstory

After serveral days of having my first production application online, my client inform me that, the application has a bug, again. The button was not working as expected for one of the users. Long story short, we found out that the bug occurs in iOS 10.2.1. So, I downloaded the Simulator for iOS 10.2 to start debugging.

Issue

It turns out that fetch is not supported in iOS 10.2. In this case, I can:

  • replace fetch with axios
  • use fetch polyfill

to solve the issue.

Lesson Learned

  1. fetch is not supported for iOS 10.2 and below.
  2. How to debug a web application using Simulator.
  3. Having more information about the environment when the bug occured is always helpful.