DEV Community: Takunda Madechangu

Paynow Integration Part 5 - Checking for payments Introduction

Takunda Madechangu — Sun, 24 Sep 2023 05:58:33 +0000

Once you have requested for a transaction to take place the next steps includes

Checking transaction status
Giving a service or a product to the client

For checking transaction you can either use

Polling
Webhooks
Hybrid

Method 1: Polling

In the polling method we are checking the status of the transaction at regular intervals.

For example we could check the transaction status every 10 or 15 seconds. If the transaction was successful or unsuccessful we take the appropriate action.

Advantages

It provides precise control over when data is retrieved or actions are taken.
Easier to implement compared to event-driven approaches.
Helps ensure predictable system behavior as data is collected at fixed intervals.
Suitable for devices and systems that do not support interrupts or events for example phones, gadgets that cant serve webhook endpoints on the internet.

Disadvantages

Consumes system resources and can lead to inefficiency, especially with frequent polling.
May introduce latency or delays in response time, as data is collected only at specified intervals.
In cases where data rarely changes, continuous polling can waste resources. Imagine spamming Paynow every second with "Whats the status of my transaction?" .....thats annoying

Method 2: Webhooks

In the webhooks method, Paynow gives us real-time updates or notifications.

These updates or notification contains the status of our transaction.

Its like ordering junk food at your favorate restaurant, you are given an order number and told to wait for order. 5 minutes later you are told......"Order #202 is ready!"

Advantages

Provides instant updates when events occur, reducing latency.
Only triggers when events happen, minimizing unnecessary requests or data transfer. No more spamming "Whats the status of my transaction?"
Well-suited for handling a large volume of events or notifications.

Disadvantages

Implementation can be more complex than polling, requiring webhook endpoints and event handling logic.
Requires careful handling to prevent potential security risks, such as unauthorized access or abuse. Imagine a malicious user updating their transaction request to get free stuff
Dependent on the stability and availability of the webhook provider's infrastructure.
Handling and troubleshooting failed webhook deliveries can be challenging.

Method 3: Hybrid

In the hybrid approach we use both polling and webhooks inorder to achieve the best of both world. Of course the has its short-comings.

For example after submitting a transaction we can quickly check for its status using polling. If it succeeds quickly we move on. If it takes time to complete we leave it to the webhook to handle that

/**
 *
 * order.js
 *
 * **/

function update_transaction(trans_id, data) {
  // Update transaction
  // Send a message to the frontend using websockets
}

function checkout(user_id, order) {
  // create a payment order and send to paynow
  // Check the status using polling
  // If anything changes call update_transaction
  // After a minute or two exit the function
}

/**
 *
 * orders.routes.js
 *
 * **/

app.post('/payment-updates', (req, res) => {
  // Confirm if its paynow
  // Retrieve transaction id
  // Call update_transaction
})

Another way could be to using polling to add an extra layer of confirmation after recieving a successful transaction update from a webhook.

I am making this up. Use whatever works with you.

Thats it guys, in the next tutorials

How to debug Flutter apps over Wi-Fi(without root)

Takunda Madechangu — Sun, 17 Oct 2021 11:17:04 +0000

Let's just say you want to debug your Flutter app on android device, you use a USB cable right?

Yes but using a USB cable has its downsides

If your charging port is loose for some reason, then a slight move will disconnect your app ☹️
On MacOS is displays a certain annoying "Please install SmartSwitch or some app" message
Lack of flexibility
Among other annoyances

So lets try debugging over wifi

Debugging over wifi

Requirements

Your phone 📱
Your machine 👨🏽‍💻
A USB cable. 〜
Your machine and phone should be connected to the same wifi.

Steps

Step 1
Connect your device to your machine using USB

Step 2
Open terminal and type the following

$ adb kill-server
$ adb tcpip 5555

This will kill current adb server and create another server which listens on all interfaces.

If it says something like this

* daemon not running; starting now at tcp:5037
* daemon started successfully
restarting in TCP mode port: 5555

Remove phone from mobile device and go to the next step

Step 3
Get you device's wifi IP address. To do this:

Go to
Settings > Connections > Click Wifi Name > View properties(Which has the IP)

Settings > About Phone > Status > IP Address(Which has IP)

Your ip should be something like 192.168.100.X

Step 4
Inside your terminal type

adb connect YOUR_IP:5555

And if it says something like this:

connected to 192.168.100.X:5555

You are good to go

Safety Concerns

While this method offers convenience and flexibility, it might not be safe to do it on a public wifi or a wifi that you don't trust. After all someone might be listening in for open ports just to do something crazy, So be careful...

How to be great at anything by Mark Manson

Takunda Madechangu — Sat, 10 Jul 2021 19:58:42 +0000

This is pretty much the only way to becoming a screaming success.
Everyone wants to be good at something, but few people realize that becoming really good at something, or mastering any skill, is no walk in the park.

They’re simple, but they’re not easy. Here’s a summary:

Step 1: The 20/80 Principle

The 80/20 Principle states that 80% of the output or results will come from 20% of the input or action. For example, in time management, businesses often found that 20% of their time created 80% of their productivity, and that 20% of their employees created 80% of the value.

So the key here is founding where the 80/20 is that is what is the 20% thats going to create 80% of the results.

Step 2: Get Feedback

Nailing anything in life requires a lot of trial and error and getting feedback from people. Coaches. Tutors. Teachers. The guy across the fence. You won’t know if you’re any good at something unless someone besides yourself tells you.

You need feedback so you can improve or make adjustments.
You should recieve feedback and you should listen!, Beware of the ego! Listen to criticism

Step 3: Practice

When you look at the people who have mastered anything throughout history, the most glaringly obvious commonality is that they simply worked their asses off more than most people, and for longer than most people. Practice literally makes perfect.

Remember there are no shortcuts. PUT IN THE WORK, REITERATE/IMPROVE, FAIL AND MOVE....

Dont be fooled by overnight success stories.

Is your Paynow integration failing? Here is what to do...

Takunda Madechangu — Tue, 06 Jul 2021 17:22:57 +0000

You have just made your first Paynow integration but you are not receiving that Paynow Popup.

You start debugging using print_r, echo, dd and print statements only to discover this message:

"The integration ID specified is currently in test mode. The authemail used must belong to the company in control of the integration ID."

So how do we fix this

You have to do the following steps

Make a test transaction.
Request to be set live.
Wait for Paynow response.
Start accepting live payments.

1. Make a test transaction.

Paynow has test numbers which you can use to make fake transactions:

Success – 0771111111

Paynow will send a SUCCESS status update message 5 seconds after the transaction is initiated.

Delayed Success – 0772222222

Paynow will send a SUCCESS status update message 30 seconds after the transaction is initiated. This simulates the user taking a longer than normal amount of time to authorize the transaction from their handset

User Cancelled – 0773333333

Paynow will send a FAILED status update message 30 seconds after the transaction is initiated. This simulates the user cancelling the mobile money transaction.

Insufficient Balance – 0774444444

Paynow will immediately fail the transaction during initiation and return an “Insufficient balance” error message.

For number use one of the number mentioned above e.g 0771111111

For authemail use the email that you used to register for Paynow e.g joshua@example.com

Now make a test transaction

For PHP users:

$payment = $paynow->createPayment('Order #123', 'joshua@example.com');
...
...
...

$response = $paynow->sendMobile($payment, "0771111111", "ecocash");

For Python generals:

payment = paynow.create_payment('Order #123', 'joshua@example.com')
...
...
...
response = paynow.send_mobile(payment, '0771111111', 'ecocash')

You will get this message in your email:

Paynow Reference: XXXXXXXX
Status: Paid (TESTING: Faked Success)
Customer Email: joshua@example.com
Customer Name: Test Customer
Customer Phone: 263772222222
Amount: $200.00
Reference: Order #123

Once you have done this then you can request it to be set live

2. Request to be set live

Log in to Paynow (paynow.co.zw)
Go to Recieve Payments
Click Other Ways To Get Paid
Scroll down an click Create/Manage Shopping Carts
Scroll down again and click Advanced Integration(If you don't have an integration) or click a Pencil icon on your right.

Now scroll down and click Request to be Set Live

3. Wait for Paynow response.

Now you wait

The time it takes to get your response is not personal 😂😂😂 and it should not take more than 3 days.

If it comes you will get "You integration has been set to live" message or something within these lines or some error message,. Basically error message come because you have skipped something.

4. Start accepting live payments.

Once live I love to test it again with small amounts just to make sure, You can test it on different platforms so you can get the feel of it.

Ok until we meet next time...

Image Credits:
SecurionPay

Preventing Burnouts, The Condensed Version

Takunda Madechangu — Mon, 28 Jun 2021 09:54:48 +0000

Ladies and Gentlemen this is how you defeat burnouts

Don't overspend your energy(mental, emotional, physical). Energy coming in should be more than energy going out.
Accept your limits.
Manage your tasks and time faithfully.
Find balance, don't overdo things.

Paynow Integration Part 5: Checking for payments

Takunda Madechangu — Mon, 22 Feb 2021 16:27:58 +0000

Once you have requested for a transaction to take place the next steps includes

Checking transaction status
Taking the correct action(giving or denying access)

In this tutorial we check if Paynow transaction has succeeded they can the correct action.

Checking if transaction is taking place

In the last part we send a transaction to Paynow and Paynow did send a dialog to our customer.

So to check if that succeeded we use this code:

if($response->success()) {
    // Check if payment is successful
}

If its true then it mean the transaction is taking place!

Checking if transaction is successful

Now lets check if the user paid

if($response->success()) {
    $pollUrl = $response->pollUrl();

    // Check the status of the transaction
    $status = $paynow->pollTransaction($pollUrl);

    if($status->paid()) {
        // Yay! Transaction was paid for
    } else {
        // No! It wasn't paid for
    }
}

So the first thing is getting a poll URL

$pollUrl = $response->pollUrl();

Then use that URL to get the status of the payment

$status = $paynow->pollTransaction($pollUrl);

Then you check the status

if($status->paid()) {
    // Some success code here
}else{
    // Some fail code here
}

This is theoretically correct but practically wrong because a real world mobile transaction can take from 8 seconds to 30 seconds.

The user has to put pin, verify if its correct then press accept, by then the code above who have announced it as a failed transaction.

So we must give some kind of grace period to the transaction checking process. To do that we use a loop plus sleep function.

$timeout = 9;
$count = 0;

while(true){
   sleep(3);

   //Check if paid
   if($status->paid()){
         // Yay! Transaction was paid for
   }

   $count++;

   if ($count > $timeout){
       // Timeout reached
    }

}

Complete Code

So the whole code from part 1 to this part will look like this:

<?php


$phone = $_POST["phone_number"]; // Sanitize data
$platform = "";

$user_email = filter_var($_POST['user_email'], FILTER_SANITIZE_EMAIL);
$invoice_name = "Invoice " . time();

$cart_id = $_POST['cart_id'];   // Sanitize id
$products = $this->get_cart_products($cart_id);


// Initialize Paynow
$paynow = new Paynow\Payments\Paynow(
    'INTEGRATION_ID',
    'INTEGRATION_KEY',
    'http://example.com/gateways/paynow/update',
    'http://example.com/return?gateway=paynow'
);

// Create Payments
$invoice_name = "Invoice " . time();
$payment = $paynow->createPayment($invoice_name, $user_email);

// Add some products
foreach($products as $product){
     $payment->add($product->name, $product->price);
}

// Detect platform and send payment
if(str_starts_with($phone, '071')){
     $platform= "onemoney";
}else if(str_starts_with($phone, '073')){
    $platform = "telecash";
}else{
    $platform = "ecocash";
}

$response = $paynow->sendMobile($payment, $phone, $platform);

// Check transaction success
if($response->success()) {
    // Get transaction poll URL
    $pollUrl = $response->pollUrl();



     $timeout = 9;
     $count = 0;

     while(true){
         sleep(3);
         // Get the status of the transaction
         $status = $paynow->pollTransaction($pollUrl);



         //Check if paid
         if($status->paid()){
           // Yay! Transaction was paid for
           // Save transactions to database and grant access
          }

          $count++;

          if ($count > $timeout){
             // Timeout reached
           }
      }
}

// Transaction failed

So that's it guys, go ahead and get paid, enjoy the rest of the week.

PayNow Integration Part 4: Mobile Payments

Takunda Madechangu — Thu, 18 Feb 2021 06:20:01 +0000

So we finished the boring parts and today we are going to do the following

Initialize Paynow
Adding Payment
Adding some products
Then sending payment to Paynow

1. Initialize Paynow

Before you can do anything you have to include PayNow and initialize it first

// include paynow here
<?php
$paynow = new Paynow\Payments\Paynow(
    'INTEGRATION_ID',
    'INTEGRATION_KEY',
    'http://example.com/gateways/paynow/update',
    'http://example.com/return?gateway=paynow'
);

This creates a PayNow instance, your keys should be correct or it will raise Integration Exception on checkout. Errors can be annoying.

2. Creating a payment

The next stage involves adding a payment to the PayNow instance you have created:

$invoice_name = "Invoice " . time();
$user_email = filter_var($_POST['user_email'], FILTER_SANITIZE_EMAIL);
$payment = $paynow->createPayment($invoice_name, $user_email);

This adds a payment to your instance you create in step 1. Once payment succeeds PayNow will send an email to the customer for transparence and reference purposes.

3. Add some products

If you have one product you can add it like this:

$payment->add('Sadza and Beans', 1.25);

If you have more than one products then you can add them like this

$products = [Object1, Object2, Object3, ...., Object10 ];

foreach($products as $product){
     $payment->add($product->name, $product->price);
}

If those products have quantities or amounts then it will be something like this

$products = [Object1, Object2, Object3, ...., Object10 ];
$total = 0;
$tax = 0.01;

foreach($products as $product){
     $total = $product->price * $product->qty;
     $tax_amount = $total * $tax;
     $total = $tax_amount + $total;
     $payment->add($product->name, $product->price);
}

You could add things like coupons, discounts, promotions and what what but well I will leave that you.

Sending payment to PayNow

After adding payment the next stage is sending the payment to payment to PayNow

$response = $paynow->sendMobile($payment, '077777777', 'ecocash');

Here were requesting for a mobile transaction to occur between our Paynow account and 0777777777 's Ecocash.

The number you get from user through forms or from database. The platform('ecocash') can be retrieved from user through forms or by auto detection

$phone = "07777777";
$platform = ""
if(str_starts_with($phone, '071')){
     $platform= "onemoney";
}else if(str_starts_with($phone, '073')){
    $platform = "telecash";
}else{
    $platform = "ecocash";
}

// Then 
$response = $paynow->sendMobile($payment, $phone, $platform);

Your users will love this 😎😎😎

So this part alone should send a message to your customer mobile asking for payment:

Of course there will be some small differences.

Ok that's it for this one in the next tutorial we will talk about checking payments.

Paynow Integration Part 3: Installation

Takunda Madechangu — Tue, 16 Feb 2021 13:39:18 +0000

In the last tutorial we got keys from PayNow, in this one we will go through installation of Paynow SDK in PHP based projects.
I will touch on these scenarios:

Composer
Manual Installation

Also make sure curl extension is enabled in your PHP

1. Composer

Type the following command to install paynow php sdk

$ composer require paynow/php-sdk

Then include it in you project like this

<?php
require_once 'path/to/vendor/autoload.php';
// your code here

If you are using Laravel include it like this

<?php
use \Paynow\Payments\Paynow;
// your code here

Thats it!

2. Manual Installation

If you don't have composer installed then Download Paynow Here

Extract it into your project directory then type this into your code

<?php
require_once 'path/to/library/autoloader.php';
// Do stuff

Example: Manual Installation

If your your folder structure is like this

- Paynow
- checkout.php
- success.php
- cart.php

Then you include Paynow like this(inside checkout.php)

<?php
require_once './Paynow/autoloader.php';

And BAM you have access to PayNow!!!

Congratulations we have finished the boring stages now we move to the interesting stuff

PayNow Integration Part 2: Getting Keys

Takunda Madechangu — Sun, 14 Feb 2021 09:23:54 +0000

Gateways or APIs needs a way of identifying their users so they can know:

who requested what
what belongs to who
who does what

To do that gateways use what are known as API keys/Integration keys. So in order to use an API or a payment gateway you must get those integration/API keys.

So lets get Integration keys for PayNow

Step 1: Creating an account

Go to PayNow and click Signup, you be presented with a big long form. Enter your details silently 🤣🤣🤣

Once you complete registration, you will be sent a link to finish off registration

So check your email and open the message

Follow the link and log in

Step 2: Setup payment bank account

This stage is intuitive you simply select options and enter details where they are needed

i. Payment Methods

Select the payment methods you want to accept

ii. Bank Accounts

Here you should enter your bank details. Please crosscheck you details before continuing.

iii. Charges

Here you select who absorbs the charges

Once done click Finish and you will be presented by this screen

Getting Keys

Now click Receive Payments on the navigation then click Other ways to get paid.

Scroll down to 3rd Party Shopping Carts & Business Systems Integration and click Create or Manage Shopping Carts.

Scroll down again to Advanced Integration and click Create Advanced Integration.

You will be presented with a form like that:

Enter details and click Save

Behold!.....The Keys!!!. 🙌🙌🙌

So you can view your Integration ID and Integration Key, you can also request account to be live mode and you can create another set of keys.

So ladies and gentlemen this is how you get PayNow keys

PayNow Integration Part 1: Intro

Takunda Madechangu — Sat, 13 Feb 2021 05:21:12 +0000

Wassup everybody, how are you doing , in this coming series of tutorials I am going to teach you how to integrate PayNow into your web app or website.

Present Day

In Zimbabwe its difficult to get access to a fully blown PayPal account likely due to sanctions (though PayPal denies the allegations) so you can only spend but you cannot receive. Which is a total rip off to entrepreneurs.....

So what's PayNow

PayNow is an online payment processing platform for Zimbabwe which allows you to make different kinds of payments from tax, fees, bills, subscriptions, donations, payouts etc.

Its like the PayPal of Zimbabwe(laughs violently). It mainly driven on Zimbabwean currency(ZWL) and United States Dollar.

Here are some of its features:

Accepts most popular electronic payment methods under a single contract.
Fast Payments
Its Secured
Its Merchants are verified
No Setup charges
It has consumer protection

PayNow Payment Gateway

PayNow also provides a payment gateway which you can use if you want to accept payments/get paid. The gateway accept the following payments:

Cards
Mobile Payments

You are about to say goodbye to no traffic ecommerce sites(laughs violently).

In the coming tutorials I am going to show you how can set it up and start accepting payments in your app asap

Enjoy your day

PayNow Integration Part 2: Getting Integration Keys

What is that made you divorce your first wife(React Native) for another wife(Flutter)?

Takunda Madechangu — Thu, 24 Dec 2020 14:27:16 +0000

What is it that turned off about about React Native?
What is it that makes you choose poligamy(both Flutter and React Native)?
What is it that makes you choose your first wife over the latter(Flutter)?

Devs lets discuss.....

Creating Laravel Desktop Apps Part 1: Setup

Takunda Madechangu — Mon, 19 Oct 2020 17:08:59 +0000

Hello there? How are you? Ever wondered if it was possible to turn that lovely Laravel project of yours into a desktop app. Well this tutorial if for you.

I will show you guys how to turn a Laravel app into a desktop app. Lets dive in...

Step 1: Download Laravel Electron

If you want to turn Laravel into a Mac Desktop App, then type the following:

git clone https://github.com/blackgeneration/Laravel-Electron-For-MAC-OS.git

If you want to turn laravel into a Windows Desktop App, the type the following:

git clone https://github.com/laravelarticle/laravel-electron.git

Theses repos are almost the same except for a few differences(platform specific tweaks)

Step 2: Install Dependencies

Navigate into the project (cd folder_name) and install dependencies:

npm install OR yarn install

This will install all required dependencies...

Step 3: Run the project

To run the project simple type:

npm start OR yarn start

For MAC OS users preface these commands with sudo like this:

sudo npm start OR sudo yarn start

This should start your project successfully....

You should see something like

Laravel Version So and So
PHP Version So and So

By the way the Laravel version used is 6 and PHP version is 7.2

Have fun!