curl --request GET \
  --url https://api.tilta.io/v1/merchants/{external_id}/mandates \
  --header 'Authorization: Bearer <token>'

const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://api.tilta.io/v1/merchants/{external_id}/mandates', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://api.tilta.io/v1/merchants/{external_id}/mandates"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.text)

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.tilta.io/v1/merchants/{external_id}/mandates",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

{
  "limit": 100,
  "offset": 0,
  "total": 140,
  "items": [
    {
      "mandate_id": "TLT PLT 00000001",
      "iban": "DE03500105177178979259",
      "created_at": 1582896122,
      "updated_at": 1582896122
    }
  ]
}

{
  "code": "BAD_REQUEST",
  "error": "Request validation failed. 1 issue found.",
  "issues": [
    {
      "code": "INVALID_TYPE",
      "path": "body.registered_at",
      "message": "Invalid type"
    }
  ]
}

{
  "error": "Unauthorized",
  "code": "UNAUTHORIZED"
}

{
  "error": "No Entity found",
  "code": "NOT_FOUND"
}