curl --request GET \
  --url https://api.railmail.app/api/v1/topics \
  --header 'X-API-Key: <api-key>'

import requests

url = "https://api.railmail.app/api/v1/topics"

headers = {"X-API-Key": "<api-key>"}

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

print(response.text)

const options = {method: 'GET', headers: {'X-API-Key': '<api-key>'}};

fetch('https://api.railmail.app/api/v1/topics', 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.railmail.app/api/v1/topics",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "X-API-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.railmail.app/api/v1/topics"

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

	req.Header.Add("X-API-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.railmail.app/api/v1/topics")
  .header("X-API-Key", "<api-key>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.railmail.app/api/v1/topics")

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

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

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

{
  "data": [
    {
      "topicKey": "APIT-1",
      "name": "Newsletter",
      "description": "Weekly news",
      "status": "ACTIVE",
      "doubleOptInEnabled": true,
      "subscriberCount": 1200,
      "activeSubscriberCount": 1180,
      "createdAt": "2026-06-01T09:00:00Z"
    }
  ],
  "pagination": {
    "page": 0,
    "size": 20,
    "totalElements": 1,
    "totalPages": 1,
    "hasNext": false,
    "hasPrevious": false
  }
}

{
  "type": "<string>",
  "title": "<string>",
  "status": 123,
  "detail": "<string>",
  "instance": "<string>",
  "timestamp": "2023-11-07T05:31:56Z",
  "errors": {}
}

{
  "type": "<string>",
  "title": "<string>",
  "status": 123,
  "detail": "<string>",
  "instance": "<string>",
  "timestamp": "2023-11-07T05:31:56Z",
  "errors": {}
}

{
  "type": "<string>",
  "title": "<string>",
  "status": 123,
  "detail": "<string>",
  "instance": "<string>",
  "timestamp": "2023-11-07T05:31:56Z",
  "errors": {}
}

{
  "type": "<string>",
  "title": "<string>",
  "status": 123,
  "detail": "<string>",
  "instance": "<string>",
  "timestamp": "2023-11-07T05:31:56Z",
  "errors": {}
}