curl --request GET \
  --url https://api.messari.io/topics/v1/classes \
  --header 'x-messari-api-key: <api-key>'

import requests

url = "https://api.messari.io/topics/v1/classes"

headers = {"x-messari-api-key": "<api-key>"}

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

print(response.text)

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

fetch('https://api.messari.io/topics/v1/classes', 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.messari.io/topics/v1/classes",
  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-messari-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.messari.io/topics/v1/classes"

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

	req.Header.Add("x-messari-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.messari.io/topics/v1/classes")
  .header("x-messari-api-key", "<api-key>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.messari.io/topics/v1/classes")

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

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

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

{
  "error": null,
  "data": [
    "Treasury Management",
    "Treasury Expense",
    "Project Team Funding",
    "Incentives Program",
    "Discontinued Product",
    "Project Strategy",
    "Partnership",
    "Token Swap or Migration",
    "Network Upgrade",
    "Governance Update",
    "Project Announcements",
    "Network Deployment",
    "Airdrop",
    "Feature Release",
    "Network Launch",
    "Token Listing",
    "Security and Hacks",
    "Protocol Exploit",
    "Vulnerability Disclosure",
    "Centralized Exchange Loss of Funds",
    "Funding",
    "Legal and Regulatory",
    "Network Congestion",
    "Blockchain Halt",
    "Node Outage",
    "Bug Disclosure",
    "Chain Split",
    "Community Update",
    "Macro Commentary",
    "Price Analysis",
    "Irrelevant Content"
  ]
}

{
  "error": "<string>"
}

{
  "error": "<string>"
}

{
  "error": "<string>"
}