curl -X POST https://api.metrifox.com/api/v1/subscriptions/9c3a7180-3a05-4a7c-9b09-2ad1c9a2b8d1/topup_credits \
  -H "x-api-key: $METRIFOX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "line_items": [
      { "credit_key": "credit_tokens", "quantity": 100 }
    ]
  }'

import requests

url = "https://{defaultHost}/api/v1/subscriptions/{subscription_id}/topup_credits"

payload = { "line_items": [
        {
            "credit_key": "credit_tokens",
            "quantity": 100
        }
    ] }
headers = {
    "x-api-key": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'x-api-key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({line_items: [{credit_key: 'credit_tokens', quantity: 100}]})
};

fetch('https://{defaultHost}/api/v1/subscriptions/{subscription_id}/topup_credits', 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://{defaultHost}/api/v1/subscriptions/{subscription_id}/topup_credits",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'line_items' => [
        [
                'credit_key' => 'credit_tokens',
                'quantity' => 100
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "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"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://{defaultHost}/api/v1/subscriptions/{subscription_id}/topup_credits"

	payload := strings.NewReader("{\n  \"line_items\": [\n    {\n      \"credit_key\": \"credit_tokens\",\n      \"quantity\": 100\n    }\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-api-key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

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

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

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://{defaultHost}/api/v1/subscriptions/{subscription_id}/topup_credits")
  .header("x-api-key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"line_items\": [\n    {\n      \"credit_key\": \"credit_tokens\",\n      \"quantity\": 100\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://{defaultHost}/api/v1/subscriptions/{subscription_id}/topup_credits")

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

request = Net::HTTP::Post.new(url)
request["x-api-key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"line_items\": [\n    {\n      \"credit_key\": \"credit_tokens\",\n      \"quantity\": 100\n    }\n  ]\n}"

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