Create an access token

curl --request POST \
  --url https://sandbox.api.bahnexpress.fi/oauth2/token \
  --header 'Authorization: Basic <encoded-value>' \
  --header 'Content-Type: application/x-www-form-urlencoded' \
  --data grant_type=client_credentials

const options = {
  method: 'POST',
  headers: {
    Authorization: 'Basic <encoded-value>',
    'Content-Type': 'application/x-www-form-urlencoded'
  },
  body: new URLSearchParams({grant_type: 'client_credentials'})
};

fetch('https://sandbox.api.bahnexpress.fi/oauth2/token', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://sandbox.api.bahnexpress.fi/oauth2/token"

payload = { "grant_type": "client_credentials" }
headers = {
    "Authorization": "Basic <encoded-value>",
    "Content-Type": "application/x-www-form-urlencoded"
}

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

print(response.text)

{
  "access_token": "eyJhbGciOiJSUzI1NiIsImtpZCI6ImV4YW1wbGUifQ.example",
  "expires_in": 900,
  "expires_at": 1785417831,
  "token_type": "Bearer",
  "scope": "orders:read orders:write"
}

{
  "error": "invalid_request",
  "error_description": "Use the client_credentials grant and optional scope field."
}

{
  "error": "invalid_client",
  "error_description": "Use the client ID and client secret with HTTP Basic."
}

{
  "error": "invalid_request",
  "error_description": "Use the client_credentials grant and optional scope field."
}