Two-factor Authentication API

You can use Two-factor Authentication API to prove a user's identity. Provision a US Short Code with a standard or custom template that specifies the custom parameters for two-factor authentication (2FA) messages. These APIs support 2FA for the US and Canada.

Two-factor authentication (also known as 2FA) provides user identification by combining two different components. In this case, a phone number associated with your user and a PIN. Before you use this API you have to Setup a Pre-approved Short Code for 2FA.

The workflow for Two-factor Authentication API is:

Two-factor Authentication workflow

  1. Send a 2FA request.
  2. Check the response codes in the response and ensure that you sent the request to Nexmo correctly.
  3. Nexmo delivers your PIN to your user's handset. Your user enters this PIN into your APP.
  4. Receive the delivery receipt at your webhook endpoint and verify delivery.

To ensure that your traffic is send over the best possible route, use Conversion API to tell us about the reliability of your 2FA communication. Adding your conversion data means Nexmo delivers your messages faster and more reliably.

Note: quality of delivery (QoD) statistics are based on delivery receipts (DLR). For the US we only receive intermediate and not handset DLRs. This means Dashboard analytics cannot show QoD statistics for short codes.

Implementing the Two-factor Authentication API workflow

To use the 2FA API you:

  1. Send a 2FA request.

    var https = require('https');
    
    var data = JSON.stringify({
     api_key: 'API_KEY',
     api_secret: 'API_SECRET',
     to: '441632960960',
     pin: 'A_PIN'
    });
    
    var options = {
     host: 'rest.nexmo.com',
     path: '/sc/us/2fa/json',
     port: 443,
     method: 'POST',
     headers: {
       'Content-Type': 'application/json',
       'Content-Length': Buffer.byteLength(data)
     }
    };
    
    var req = https.request(options);
    
    req.write(data);
    req.end();
    
    var responseData = '';
    req.on('response', function(res){
     res.on('data', function(chunk){
       responseData += chunk;
     });
    
     res.on('end', function(){
       console.log(JSON.parse(responseData));
     });
    });
    
    <?php
    $url = 'https://rest.nexmo.com/sc/us/2fa/json?' . http_build_query([
            'api_key' => 'API_KEY',
            'api_secret' => 'API_SECRET',
            'to' => '441632960960',
            'pin' => 'A_PIN'
        ]);
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $response = curl_exec($ch);
    
    import urllib
    
    params = {
        'api_key': 'API_KEY',
        'api_secret': 'API_SECRET',
        'to': '441632960960',
        'pin' : 'A_PIN'
    }
    
    url = 'https://rest.nexmo.com/sc/us/2fa/json?' + urllib.urlencode(params)
    
    response = urllib.urlopen(url)
    print response.read()
    
    require "net/http"
    require "uri"
    
    uri = URI.parse("https://rest.nexmo.com/sms/json")
    params = {
        'api_key' => 'API_KEY',
        'api_secret' => 'API_SECRET',
        'to' => '441632960960',
        'pin' => 'A_PIN'
    }
    
    response = Net::HTTP.post_form(uri, params)
    
    puts response.body
    
  2. Check the response codes in the response and ensure that you sent the request to Nexmo correctly.

    // Decode the json object you retrieved when you ran the request.
    
    var decodedResponse = JSON.parse(responseData);
    
    console.log('You sent ' + decodedResponse['message-count'] + ' messages.\n');
    
    decodedResponse['messages'].forEach(function(message) {
        if (message['status'] === "0") {
          console.log('Success ' + decodedResponse['message-id']);
        }
        else {
          console.log('Error ' + decodedResponse['status']  + ' ' +  decodedResponse['error-text']);
        }
    });
    
    <?php
    // Decode the json object you retrieved when you ran the request.
    $decoded_response = json_decode($response, true);
    
    error_log('You sent ' . $decoded_response['message-count'] . ' messages.');
    
    foreach ( $decoded_response['messages'] as $message ) {
        if ($message['status'] == 0) {
            error_log("Success " . $message['message-id']);
        } else {
            error_log("Error {$message['status']} {$message['error-text']}");
        }
    }
    
    import json
    
    #Using the response object from the request
    
    if response.code == 200 :
        data = response.read()
        #Decode JSON response from UTF-8
        decoded_response = json.loads(data.decode('utf-8'))
        # Check if your messages are succesful
        messages = decoded_response["messages"]
        for message in messages:
            if message["status"] == "0":
                print "success"
    else :
        #Check the errors
        print "unexpected http {code} response from nexmo api". response.code
    
    require 'json'
    
    # Decode the json object from the response object you retrieved from the request.
    if response.kind_of? Net::HTTPOK
      decoded_response = JSON.parse(response.body )
    
      messagecount = decoded_response["message-count"]
    
      decoded_response["messages"].each do |message|
        if message["status"] == "0"
            p "message " + message["message-id"] + " sent successfully.\n"
          else
            p "message has error " + message["status"]  + " " + message["error-text"]
        end
      end
    else
      puts response.code + " error sending message"
    end
    
  3. Nexmo delivers your PIN to your user's handset. Your user enters this PIN into your APP.

  4. Receive the delivery receipt at your webhook endpoint so you can see:

    1. If the status was successful.
    2. When and how the call was made.
    3. How much the call cost.
    var app = require('express')();
    app.set('port', (process.env.PORT || 5000));
    app.use(require('body-parser').urlencoded({
        extended: false
    }));
    // Handle GET webhook
    app.get('/delivery-receipt-webhook', function(req, res) {
        handleWebhook(req.query, res);
    });
    // Handle POST webhook
    app.post('/delivery-receipt-webhook', function(req, res) {
        handleWebhook(req.body, res);
    });
    
    function handleWebhook(params, res) {
        if (!params['status'] || !params['messageId']) {
            console.log('This is not a delivery receipt');
        } else {
            //This is a DLR, check that your message has been delivered correctly
            if (params['status'] !== 'delivered') {
                console.log("Fail:", params['status'], ": ", params['err-code']);
            } else {
                console.log("Success");
              /*
                * The following parameters in the delivery receipt should match the ones
                * in your request:
                * Request - from, dlr - to\n
                * Response - message-id, dlr - messageId
                * Request - to, Responese - to, dlr - msisdn
                * Request - client-ref, dlr - client-ref
               */
            }
        }
        res.sendStatus(200);
    }
    app.listen(app.get('port'), function() {
        console.log('Example app listening on port', app.get('port'));
    });
    
    <?php
    // work with get or post
    $request = array_merge($_GET, $_POST);
    
    // Check that this is a delivery receipt.
    if (!isset($request['messageId']) OR !isset($request['status'])) {
        error_log('This is not a delivery receipt');
        return;
    }
    
    //Check if your message has been delivered correctly.
    if ($request['status'] == 'delivered') {
        error_log("Your message to {$request['msisdn']} (message id {$request['messageId']}) was delivered.");
        error_log("The cost was {$request['price']}.");
    } elseif ($request['status'] != 'accepted') {
        error_log("Your message to {$request['msisdn']} (message id {$request['messageId']}) was accepted by the carrier.");
        error_log("The cost was {$request['price']}.");
    } else {
        error_log("Your message to {$request['msisdn']} has a status of: {$request['status']}.");
        error_log("Check err-code {$request['err-code']} against the documentation.");
    }
    
    #To run this code, replace the MyHandler in
    #https://wiki.python.org/moin/BaseHttpServer With the following code,
    from urlparse import urlparse, parse_qs
    class MyHandler(BaseHTTPServer.BaseHTTPRequestHandler):
        def do_GET(s):
            """Tell Nexmo that you have recieved the GET request."""
            s.send_response(200)
            s.send_header("Content-type", "text/html")
            s.end_headers()
            """Parse parameters in the GET request"""
            parsed_path = urlparse(s.path)
            try:
                    delivery_receipt = dict(
                    [p.split('=') for p in parsed_path[4].split('&')])
            except:
                    delivery_receipt = {}
    
                """Check the is a delivery receipt"""
            if 'text' in delivery_receipt:
                print ("This is not a delivery receipt")
            elif delivery_receipt['status'] != "delivered":
                print "Fail:" + delivery_receipt['status']
                + ": " + delivery_receipt['err-code'] +  ".\n"
            else:
                print "success"
                    """Handle the DLR for a message sent succesfully
                        The following parameters in the delivery receipt should
                        match the ones in your request:
                         * Request - from, dlr - to
                         * Response - message-id, dlr - messageId
                         * Request - to, Responese - to, dlr - msisdn
                         * Request - client-ref, dlr - client-ref
                        Use the documentation to check the values."""
    
    require 'socket'
    require 'uri'
    
    def handle_delivery_receipt(request_line)
    #Parse the parameters and check if the message was delivered
      params = URI::decode_www_form(request_line).to_h
      if params["status"].nil? or params["messageId"].nil?
        p ('This is not a delivery receipt')
      elsif params["status"] != 'delivered'
        p ("Your request " + params["status"] +
        "because of " + params["err-code"] );
      else
        p ("Success for request " + params['messageId'] )
      end
    end
    
    # Initialize a TCPServer
    server = TCPServer.new('', 9999)
    
    # Wait for connections
    loop do
      # Wait until a client connects
      socket = server.accept
    
      method, path = socket.gets.split
      handle_delivery_receipt(path)
    
      # Return the 200 so Nexmo does not send the DLR to you repeatedly
      socket.print "HTTP/1.1 200 OK"
      # Close the socket, terminating the connection
      socket.close
    end
    

Note: remember to return a status code when you receive the delivery receipt.