curl --request POST \
  --url https://sandbox.api.fin.com/v1/oauth/token \
  --header 'Content-Type: application/json' \
  --data '
{
  "client_id": "<string>",
  "client_secret": "<string>"
}
'

const url = 'https://sandbox.api.fin.com/v1/oauth/token';
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({client_id: '<string>', client_secret: '<string>'})
};

fetch(url, options)
  .then(res => res.json())
  .then(json => console.log(json))
  .catch(err => console.error(err));

HttpResponse<String> response = Unirest.post("https://sandbox.api.fin.com/v1/oauth/token")
  .header("Content-Type", "application/json")
  .body("{\n  \"client_id\": \"<string>\",\n  \"client_secret\": \"<string>\"\n}")
  .asString();

import requests

url = "https://sandbox.api.fin.com/v1/oauth/token"

payload = {
    "client_id": "<string>",
    "client_secret": "<string>"
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://sandbox.api.fin.com/v1/oauth/token"

	payload := strings.NewReader("{\n  \"client_id\": \"<string>\",\n  \"client_secret\": \"<string>\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

{
  "access_token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",
  "access_token_ttl": "2025-12-28 10:34:45+00",
  "refresh_token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",
  "refresh_token_ttl": "2025-12-28 10:34:45+00",
  "current_time": "2025-12-21 10:34:45+00"
}

{
  "message": "Authentication failed"
}

{
  "message": "<string>",
  "errors": [
    {}
  ]
}