`$fetch` interceptor not modifying the retried request when a body is present

[cmgdragon]

`$fetch` interceptor not modifying the retried request when a body is present

[danielroe]

Would you see if you can reproduce this in pure Nitro (reproduction sandbox), and if so, raise there? 🙏

It’s likely an ofetch issue if so.

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Start a new pull request in StackBlitz Codeflow.

• nuxt-starter-jcgqeq (Open reproduction)

[cmgdragon]

Would you see if you can reproduce this in pure Nitro (reproduction sandbox), and if so, raise there? 🙏

It’s likely an ofetch issue if so.

I've been able to reproduce it with a simple express server + simple vue app (no Nuxt/Nitro needed).. so It may truly be an ofetch issue.
Should I report it directly to unjs/ofetch or do the same with Nitro instead of express and report it there..?

[danielroe]

No, it's even better if you can report directly to ofetch ❤️

[cmgdragon]

I just realized what's going on here. $fetch is transforming the headers object into a Headers class if there's a body and the method is other than GET; so if we modify the headers just as shown in the useFetch documentation, when the request is retried and loops back to the onRequest interceptor, these are being added as extra properties of the Headers object and ignored later

A proposed solution is to normalize the object before hitting the onRequest (unjs/ofetch#392)