Selling Pay-Per-Download Products

As there is already an in-depth article on installing a payment gateway (specifically, for eZ Authorize), this article will skip most of the theory and focus on the practical steps.

In our example, we are requiring buyers to pay via PayPal before they can access the downloadable products. The eZ PayPal account is a workflow event that will be triggered at the correct step in the checkout process. It will handle the payment process on the PayPal site and return to the example site upon successful payment.

PayPal Sandbox account

When setting up any sort of PayPal integration with a website, it is useful to sign up for a free PayPal Sandbox account. With such an account, you can create a test buyer and test seller account and buy all the example products you want! Make sure you have a PayPal Sandbox account before continuing, as you will need to use some test PayPal accounts shortly.

Note that in order to properly test the PayPal integration, you must also do your testing on a website that has a publicly available address (that is, it cannot just be "localhost") in order for the PayPal website to be able to communicate back.

Installing and configuring the eZ PayPal extension

The eZ PayPal extension can be downloaded at http://svn.ez.no/svn/extensions/ezpaypal/trunk/.

Place the contents of that "trunk" folder into the folder extension/ezpaypal in your eZ Publish installation. Then, activate the extension globally in settings/override/site.ini.append.php, adding it to the "ActiveExtensions" list:

[ExtensionSettings]
ActiveExtensions[]
ActiveExtensions[]=ezpaypal

The eZ PayPal extension also has some of its own settings in extension/ezpaypal/settings/paypal.ini. The only ones that we need to worry about for now are the PayPal server name (which we will set to the PayPal Sandbox server) and the test PayPal seller account:

[ServerSettings]
#ServerName=https://www.paypal.com
ServerName=https://www.sandbox.paypal.com
RequestURI=/cgi-bin/webscr

# field: "business"
# e-mail of receiver
Business=yoursandboxaccount@blah.com

A final requirement of the eZ PayPal extension is that you force buyers on your site to have eZ Publish user accounts. To do so, make sure that the webshop account handler is set to "ezdefault" in settings/override/shopaccount.ini.append.php:

[AccountSettings]
Handler=ezdefaultan

To ensure that all of these configurations take effect, clear all caches, either from the right side of the Administration Interface, or on the command line from the root of your install:

php bin/php/ezcache.php –clear-all

As is the usual process with eZ Publish 4.0 and higher, you must now re-generate the autoloads file, either on the Setup > Extensions page in the Administration Interface, or on the command line from the root of your install:

php bin/php/ezpgenerateautoloads.php -e -p

 ("-e" to generate the extension autoloads and "-p" -- available in eZ Publish 4.1 and higher -- to show a nice progress bar)

Setting up the eZ PayPal workflow

Although the eZ PayPal extension is now activated and ready to use, you must also instruct eZ Publish on when to actually run it. This is where we will plug it into the workflow system. This involves creating a workflow group, creating the workflow, and assigning it to run at the appropriate trigger; all of this is done in the Administration Interface.

First, on the "Setup > Workflows" page, click the "New workflow group" button. Name the workflow group "Payment gateways". Workflow groups serve only to organize workflows.

When viewing the new workflow group, click the "New workflow" button. Name the workflow "Payment and Fulfillment", select "Event / Payment Gateway" from the dropdown list, and click the "Add event" button.

 Payment and Fulfillment Workflow

Select the "Paypal" type, add a useful description, then click the "OK" button.

Your new workflow can now be assigned to the appropriate trigger. Click the "Triggers" link in the left menu, then select "Payment and Fulfillment" as the workflow to run before the "checkout" function of the "shop" module.

 Shop Checkout Before Trigger

More testing

To make sure that your PayPal workflow is running properly, you can buy your PDF product using your Test User account. However, first log in to your PayPal Sandbox account.

After you add the PDF product to the shopping cart, proceed to check out, and click the "Confirm" button, you should be redirected to the PayPal Sandbox site, prompting you to log in and pay for the product (using your test PayPal account).