curl --request POST \
  --url https://api.sendx.io/api/v1/rest/send/template \
  --header 'Content-Type: application/json' \
  --header 'X-Team-ApiKey: <api-key>' \
  --data '
{
  "from": {
    "email": "from@example.com",
    "name": "From Name"
  },
  "to": [
    {
      "email": "to@example.com",
      "name": "To Name",
      "customFields": {}
    }
  ],
  "subject": "Your Subject Here",
  "template": "template_f3lJvTEhSjKGVb5Lwc5SWS"
}
'

import requests

url = "https://api.sendx.io/api/v1/rest/send/template"

payload = {
    "from": {
        "email": "from@example.com",
        "name": "From Name"
    },
    "to": [
        {
            "email": "to@example.com",
            "name": "To Name",
            "customFields": {}
        }
    ],
    "subject": "Your Subject Here",
    "template": "template_f3lJvTEhSjKGVb5Lwc5SWS"
}
headers = {
    "X-Team-ApiKey": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-Team-ApiKey': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    from: {email: 'from@example.com', name: 'From Name'},
    to: [{email: 'to@example.com', name: 'To Name', customFields: {}}],
    subject: 'Your Subject Here',
    template: 'template_f3lJvTEhSjKGVb5Lwc5SWS'
  })
};

fetch('https://api.sendx.io/api/v1/rest/send/template', 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.sendx.io/api/v1/rest/send/template",
  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([
    'from' => [
        'email' => 'from@example.com',
        'name' => 'From Name'
    ],
    'to' => [
        [
                'email' => 'to@example.com',
                'name' => 'To Name',
                'customFields' => [
                                
                ]
        ]
    ],
    'subject' => 'Your Subject Here',
    'template' => 'template_f3lJvTEhSjKGVb5Lwc5SWS'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-Team-ApiKey: <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://api.sendx.io/api/v1/rest/send/template"

	payload := strings.NewReader("{\n  \"from\": {\n    \"email\": \"from@example.com\",\n    \"name\": \"From Name\"\n  },\n  \"to\": [\n    {\n      \"email\": \"to@example.com\",\n      \"name\": \"To Name\",\n      \"customFields\": {}\n    }\n  ],\n  \"subject\": \"Your Subject Here\",\n  \"template\": \"template_f3lJvTEhSjKGVb5Lwc5SWS\"\n}")

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

	req.Header.Add("X-Team-ApiKey", "<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://api.sendx.io/api/v1/rest/send/template")
  .header("X-Team-ApiKey", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"from\": {\n    \"email\": \"from@example.com\",\n    \"name\": \"From Name\"\n  },\n  \"to\": [\n    {\n      \"email\": \"to@example.com\",\n      \"name\": \"To Name\",\n      \"customFields\": {}\n    }\n  ],\n  \"subject\": \"Your Subject Here\",\n  \"template\": \"template_f3lJvTEhSjKGVb5Lwc5SWS\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.sendx.io/api/v1/rest/send/template")

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

request = Net::HTTP::Post.new(url)
request["X-Team-ApiKey"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"from\": {\n    \"email\": \"from@example.com\",\n    \"name\": \"From Name\"\n  },\n  \"to\": [\n    {\n      \"email\": \"to@example.com\",\n      \"name\": \"To Name\",\n      \"customFields\": {}\n    }\n  ],\n  \"subject\": \"Your Subject Here\",\n  \"template\": \"template_f3lJvTEhSjKGVb5Lwc5SWS\"\n}"

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