ReactJS seems to turn POST requests into GET requests - reactjs

Question

I'm using React and the fetch API to do a POST request to a user authentication backend. I can do this POST request below with Postman, and I get the correct JWT back, but oddly - whenever I use the following code in React, the POST request somehow hits the server as a GET request.
Code in React:
return this.fetch('http://fakeURL.com/auth', {
method: 'POST',
headers: {
Accept: 'application/json',
'Content-Type': 'application/json',
},
body: JSON.stringify({
"email": "email#email.com",
"password": "password",
})
}).then(res => {
this.setToken(res.token);
return Promise.resolve(res);
})
The logs show (first the pre-flight request):
Request URL: http://fakeURL.com/auth
Request Method: OPTIONS
Status Code: 200 OK
Referrer Policy: no-referrer-when-downgrade
And the actual request:
Request URL: http://fakeURL.com/auth
Request Method: GET
Status Code: 405 METHOD NOT ALLOWED
Referrer Policy: no-referrer-when-downgrade
Things I've tried:
Running the app both locally and in an AWS S3 bucket (with CORS configured to allow all methods, and from any origin)
Using Flask on our backend to enable CORS
Hitting our backend via Postman with the same API POST request (when we use Postman, the API request works as intended, as a POST that returns a token)
Hitting other URLs (e.g. http://httpbin.org/post) to see if my code can hit those endpoints with a POST rather than a GET... and those endpoints see GET requests as well (instead of the intended POST)
This is so confusing - what could possibly cause our POST request to go out as a GET request? I feel like we've eliminated every possibly cause outside of something weird happening in React. Thanks for the help!

Answer 1

npm install --save axios
on your auth page:
import axios from 'axios'
Modify your post so instead of using fetch:
login(emailValue, passwordValue) {
return axios({
url: `yourAuthURL`,
method: 'POST',
headers: {
Accept: 'application/json',
'Content-Type': 'application/json',
},
data: {
"email": emailValue,
"password": passwordValue,
}
}).then(res => {
console.log(res);
})
}