Azure Function snippet for sending text messages with Twilio

SendSms.cs

[FunctionName("SendSms")]
public static async Task<IActionResult> Run(
  // This is an HTTP trigger accepting POST requests. That's why we are able to invoke it using Postman.
  [HttpTrigger(AuthorizationLevel.Function, "post", Route = "tygerbytes/sygnal")] HttpRequest req,
  ILogger log,
  ExecutionContext context)
{
  // The FuncConfig class encapsulates environment-specific settings like those
  //  TWILIO... environment variables.
  var funcConfig = new FuncConfig(context);

  // Grab the request body, the thing we added as "raw" JSON content in Postman.
  string requestBody = await new StreamReader(req.Body).ReadToEndAsync();

  // "Deserialize" the JSON string into an SendSmsRequest object.
  var request = JsonConvert.DeserializeObject<SendSmsRequest>(requestBody);
  if (!request.IsValid())
  {
    // If this request is malformed, return a 400 Bad Request HTTP code.
    //  See the SendSmsRequest class for more info.
    return new BadRequestObjectResult(request.InvalidRequestReason());
  }

  // Convert the request object back to JSON (serialize) and log it.
  //  Wasteful? Perhaps. But very useful when debugging. :)
  log.LogInformation(Utils.ToJson(request));

  // Initialize the Twilio engine. Vroooom!
  await funcConfig.TwilioInitAsync();
  try
  {
    // Convert the semi-colon delimited list of phone numbers to an array
    //  of PhoneNumber objects, then send an SMS to each one.
    foreach (var number in Utils.SplitTo<PhoneNumber>(request.ToPhoneNumbers))
    {
      // Creating the MessageResource sends the SMS.
      var messageResource = MessageResource.Create(
        // Note that we append the SMS signature to the end of the message.
        body: $"{request.Message}\n{funcConfig.SmsSignature}",
        from: funcConfig.TwilioPhoneNumber,
        to: number
      );
      // Log it along with the status message returned.
      log.LogInformation($"SMS to {number} has been {messageResource.Status}.");
    }
  }
  catch (Exception ex)
  {
    // Uh-oh. Something went wrong. Send a HTTP 500 Internal Server error code,
    //  including the exception message.
    return new ObjectResult(ex.Message)
    {
      StatusCode = 500
    };
    throw;
  }

  // Yay! Everything worked. Return an HTTP 200 OK.
  return new OkObjectResult($"Message sent.");
}