SMTP relay and email API for reliable transactional email delivery

curl "https://cpaas.zoho.com/v1.1/email" \
-X POST \
-H "Accept: application/json" \
-H "Content-Type: application/json" \
-H "Authorization: [Authorization key]"  \
-d '{
"from": {"address": "yourname@yourdomain.com"},
"to": [{
    "email_address": {
        "address": "receiver@yourdomain.com",
        "name": "Receiver"
    }
}],
"subject":"Test Email",
"htmlbody":" Test email sent successfully. "}'    
                                            

// https://www.npmjs.com/package/zeptomail

// For ES6
import { SendMailClient } from "zeptomail";

// For CommonJS
// var { SendMailClient } = require("zeptomail");

const url = "cpaas.zoho.com/";
const token = "[Authorization key]";

let client = new SendMailClient({ url, token });

client
  .sendMail({
  from: {
      address: "yourname@yourdomain.com",
      name: "noreply"
  },
  to: [
      {
      email_address: {
          address: "receiver@yourdomain.com",
          name: "Receiver"
      },
      },
  ],
  subject: "Test Email",
  htmlbody: " Test email sent successfully.",
  })
  .then((resp) => console.log("success"))
  .catch((error) => console.log("error"));
                                            

using System;
using System.Net;
using System.Text;
using System.IO;
using System.Net.Http;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace Rextester {
  public class Program {
  public static void Main(string[] args) {
  System.Net.ServicePointManager.SecurityProtocol = 
    System.Net.SecurityProtocolType.Tls12;
  var baseAddress = "https://cpaas.zoho.com/v1.1/email";
  
  var http = (HttpWebRequest)WebRequest.Create(new Uri(baseAddress));
  http.Accept = "application/json";
  http.ContentType = "application/json";
  http.Method = "POST";
  http.PreAuthenticate = true;
  http.Headers.Add("Authorization", "[Authorization key]");
  JObject parsedContent = JObject.Parse("{"+
    "'from': {'address': 'yourname@yourdomain.com'},"+
    "'to': [{'email_address': {"+
    "'address': 'receiver@yourdomain.com',"+
    "'name': 'Receiver'"+
    "}}],"+
    "'subject':'Test Email',"+
    "'htmlbody':' Test email sent successfully.'"+
  "}");
  Console.WriteLine(parsedContent.ToString());
  ASCIIEncoding encoding = new ASCIIEncoding();
  Byte[] bytes = encoding.GetBytes(parsedContent.ToString());
  
  Stream newStream = http.GetRequestStream();
  newStream.Write(bytes, 0, bytes.Length);
  newStream.Close();
  
  var response = http.GetResponse();
  
  var stream = response.GetResponseStream();
  var sr = new StreamReader(stream);
  var content = sr.ReadToEnd();
  Console.WriteLine(content);
  }
  }
}
                                            

import requests

url = "https://cpaas.zoho.com/v1.1/email"

payload = """{
    "from": { 
      "address": "yourname@yourdomain.com"
    },
    "to": [{
      "email_address": {
        "address": "receiver@yourdomain.com",
        "name": "Receiver"
      }}],
    "subject":"Test Email",
    "htmlbody":"Test email sent successfully."
    }"""
headers = {
 'accept': "application/json",
 'content-type': "application/json",
 'authorization': "[Authorization key]",
}

response = requests.request("POST",url,data=payload,headers=headers)

print(response.text)
                                            

<?php
$curl = curl_init();
curl_setopt_array($curl, array(
    CURLOPT_URL => "https://cpaas.zoho.com/v1.1/email",
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_ENCODING => "",
    CURLOPT_MAXREDIRS => 10,
    CURLOPT_TIMEOUT => 30,
    CURLOPT_SSLVERSION => CURL_SSLVERSION_TLSv1_2,
    CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
    CURLOPT_CUSTOMREQUEST => "POST",
    CURLOPT_POSTFIELDS => '{
    "from": { "address": "yourname@yourdomain.com"},
    "to": [
            {
            "email_address": {
                "address": "receiver@yourdomain.com",
                "name": "Receiver"
            }
            }
        ],
    "subject":"Test Email",
    "htmlbody":" Test email sent successfully. ",
    }',
    CURLOPT_HTTPHEADER => array(
    "accept: application/json",
    "authorization: [Authorization key]",
    "cache-control: no-cache",
    "content-type: application/json",
    ),
    ));

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

    curl_close($curl);

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

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

import org.json.JSONObject;

public class JavaSendapi {
  public static void main(String[] args) throws Exception {
  String postUrl = "https://cpaas.zoho.com/v1.1/email";
  BufferedReader br = null;
  HttpURLConnection conn = null;
  String output = null;
  StringBuffer sb = new StringBuffer();
  try {
    URL url = new URL(postUrl);
    conn = (HttpURLConnection) url.openConnection();
    conn.setDoOutput(true);
    conn.setRequestMethod("POST");
    conn.setRequestProperty("Content-Type", "application/json");
    conn.setRequestProperty("Accept", "application/json");
    conn.setRequestProperty("Authorization", "[Authorization key]");
    JSONObject object = new JSONObject("{\n" +
    "  \"from\": {\n" +
    "    \"address\": \"yourname@yourdomain.com\"\n" +
    "  },\n" +
    "  \"to\": [\n" +
    "    {\n" +
    "      \"email_address\": {\n" +
    "        \"address\": \"receiver@yourdomain.com\",\n" +
    "        \"name\": \"Receiver\"\n" +
    "      }\n" +
    "    }\n" +
    "  ],\n" +
    "  \"subject\": \"Test Email\",\n" +
    "  \"htmlbody\": \" Test email sent successfully.\"\n" +
    "}");
    OutputStream os = conn.getOutputStream();
    os.write(object.toString().getBytes());
    os.flush();
    br = new BufferedReader(
    new InputStreamReader((conn.getInputStream()))
    );
    while ((output = br.readLine()) != null) {
    sb.append(output);
    }
    System.out.println(sb.toString());
  } catch (Exception e) {
      br = new BufferedReader(
        new InputStreamReader((conn.getErrorStream()))
      );
      while ((output = br.readLine()) != null) {
        sb.append(output);
      }
      System.out.println(sb.toString());
    } finally {
        try {
          if (br != null) {
          br.close();
          }
        } catch (Exception e) {
          e.printStackTrace();
        }
        try {
          if (conn != null) {
            conn.disconnect();
          }
        } catch (Exception e) {
          e.printStackTrace();
        }
      }
  }
}