Send params from frontend to be used in a NodeJS Get request - node.js

Question

I am trying to pass data to my Node.js backend in order to use it in a get request to an API.
For example:
Server.js
const PORT = 8000
const axios = require('axios').default
const express = require('express')
const app = express()
const cors = require('cors')
app.use(cors())
require('dotenv').config()
app.use(express.json())
app.get('/convertedAmount', (req, res) => {
const contentBody = req.body
const options = {
method: 'GET',
url: 'https://currency-converter5.p.rapidapi.com/currency/convert',
params: {format: 'json', from: contentBody.primaryCurrency, to:
contentBody.secondaryCurrency, amount: contentBody.primaryCurrencyAmount},
headers: {
'x-rapidapi-host': process.env.RAPIDAPI_HOST,
'x-rapidapi-key': process.env.RAPIDAPI_KEY,
},
}
axios
.request(options)
.then((response) => {
res.json(response.data)
})
.catch((error) => {
console.error(error)
})
})
app.listen(PORT, () => console.log(`server running on PORT ${PORT}`))
The issue is, I don't know how to pass data to the backend from the frontend, without making it a POST request. But that doesn't work if I make a POST request to the rapidAPI url. So the backend needs to stay the same.
My question is, how would I write the frontend part for this?
Using a POST request in the frontend sends the data with the req.body, but I cant get the data to display in my browser on localhost:8000/convertedAmount.
Thank you
My attempt is:
Frontend.js
...
axios.post('/convertedAmount', {
primaryCurrency: 'USD',
secondaryCurrency: 'GBP',
primaryCurrencyAmount: 1
})
.then((response) => {
console.log(response);
}, (error) => {
console.log(error);
})
...

Answer 1

You shouldn't be trying to send data in the body (such as in req.body) through a GET request. That is what a POST request is for.
With a GET request, you should pass data (such as a user id) as a parameter. Basically, in the url string.
FRONTEND
axios.get("/convertedAmount/USD/GBP/1")
BACKEND
app.get("/convertedAmount/:primaryCurrency/:secondaryCurrency/:primaryCurrencyAmount", (req, res)=>{
console.log(req.params.primaryCurrency);
console.log(req.params.secondaryCurrency);
console.log(req.params.primaryCurrencyAmount);
});
Alternatively, you could use query strings, which would look like this:
FRONTEND
axios.get("/convertedAmount?primaryCurrency=USD&secondaryCurrency=GBP&primaryCurrencyAmount=1")
BACKEND
app.get("/convertedAmount*", (req, res)=>{
console.log(req.query.primaryCurrency);
console.log(req.query.secondaryCurrency);
console.log(req.query.primaryCurrencyAmount);
});