curl --request GET \
  --url https://api.example.com/subscriptions/{id}/invoices/{invoiceId} \
  --header 'client_id: <api-key>' \
  --header 'secret_key: <api-key>'

import requests

url = "https://api.example.com/subscriptions/{id}/invoices/{invoiceId}"

headers = {
    "client_id": "<api-key>",
    "secret_key": "<api-key>"
}

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

print(response.text)

const options = {method: 'GET', headers: {client_id: '<api-key>', secret_key: '<api-key>'}};

fetch('https://api.example.com/subscriptions/{id}/invoices/{invoiceId}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.example.com/subscriptions/{id}/invoices/{invoiceId}",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "client_id: <api-key>",
    "secret_key: <api-key>"
  ],
]);

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

curl_close($curl);

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

package main

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

func main() {

	url := "https://api.example.com/subscriptions/{id}/invoices/{invoiceId}"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("client_id", "<api-key>")
	req.Header.Add("secret_key", "<api-key>")

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

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

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.get("https://api.example.com/subscriptions/{id}/invoices/{invoiceId}")
  .header("client_id", "<api-key>")
  .header("secret_key", "<api-key>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.example.com/subscriptions/{id}/invoices/{invoiceId}")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Get.new(url)
request["client_id"] = '<api-key>'
request["secret_key"] = '<api-key>'

response = http.request(request)
puts response.read_body

{
  "id": "<string>",
  "number": 123,
  "customer": {
    "id": "<string>",
    "name": "<string>",
    "federalTaxId": "<string>",
    "contact": {
      "phone": {
        "countryCode": "<string>",
        "areaCode": "<string>",
        "phoneNumber": "<string>"
      },
      "email": "<string>"
    },
    "address": {
      "street": "<string>",
      "number": "<string>",
      "neighborhood": "<string>",
      "city": "<string>",
      "state": "<string>",
      "zipCode": "<string>",
      "country": "<string>",
      "complement": "<string>"
    },
    "createdAt": "<string>",
    "externalCode": "<string>"
  },
  "supplier": {
    "id": "<string>",
    "name": "<string>",
    "businessName": "<string>",
    "federalTaxId": "<string>",
    "address": {
      "street": "<string>",
      "number": "<string>",
      "neighborhood": "<string>",
      "city": "<string>",
      "state": "<string>",
      "zipCode": "<string>",
      "country": "<string>",
      "complement": "<string>"
    },
    "createdAt": "<string>",
    "contact": {
      "phone": {
        "countryCode": "<string>",
        "areaCode": "<string>",
        "phoneNumber": "<string>"
      },
      "email": "<string>"
    },
    "externalCode": "<string>"
  },
  "referenceStartDate": "<string>",
  "referenceEndDate": "<string>",
  "items": [
    {
      "id": "<string>",
      "invoiceId": "<string>",
      "componentId": "<string>",
      "transactionId": "<string>",
      "description": "<string>",
      "price": "<string>",
      "referencePeriod": {
        "startDate": "<string>",
        "endDate": "<string>"
      },
      "createdAt": "<string>",
      "metadata": {},
      "externalCode": "<string>",
      "idempotencyKey": "<string>"
    }
  ],
  "createdAt": "<string>",
  "totalPrice": "<string>",
  "dueDate": "<string>",
  "description": "<string>",
  "externalCode": "<string>",
  "issuedAt": "<string>",
  "canceledAt": "<string>",
  "metadata": {},
  "brokerReconciliationId": "<string>"
}