Licenses are a way to let your software know about what functionality (if any) it should expose as it runs.

A License Holder is an individual or company that is identified by a unique combination of Name and Email Address and who may have one or more licenses for one or more of your Products.

As described on the Learn About Products page, Zarqon supports several approaches to licensing your Product, and by the time you get to the point of issuing licenses, you'll have chosen one of them. The License Maintenance Panel will allow you to issue Licenses for the Products you've defined, and it's interface will vary depending upon how you've defined your product, as you'll see later in this article.

Once a License Holder has been issued a License, your application will be able to validate the License and operate based it's contents.

Maintaining Licenses and License Holders

From the Overview Panel, there are two ways to access the License Maintenance Panel.

If you have any License Holders the and you want to edit, revoke or add a licenses to an existing License Holder, you can select one from the combo-box and click the big, handy 'Manage License Holder' button on the Overview Panel.

If you haven't issued any Licenses yet, or you just want to issue one to a new License Holder, then click the 'Licenses' link on the Main Menu at the bottom right of the screen.

Adding a License Holder

Before you can issue a license, you first need to define a License Holder. You do this all in one step, creating the License Holder, adding Licenses and then saving the License Holder, which also automatically rewrites all their Licenses to keep them in sync with the master License Holder record.

When you navigate to the License Maintenance Panel it will show a list of your existing License Holders and their email addresses. For this exercise we'll begin with a License Holder already added so that you can see that when you select one, you can click 'Manage License Holder' to edit. This is essentially the same as selecting the License Holder from the Overview Panel and clicking 'Manage License Holder' there. In our case we'll click 'Add License Holder' to add a new one.

The License Holder Form

The License Holder Form simply collects the name and email address of the License Holder and allows you to add or modify the associated Licenses. Fill out the License Holder Click the 'New License' icon above the Licenses list.

The Issue a License Dialog

The first step of issuing a license is to choose the Product that the License will govern. A License can only contain one Product. However a License Holder can have multiple Licenses for the same Product.

In the Issue a License dialog, you can choose the Product and optionally set an expiry period for the entire License. Feature Sets and Features do not inherit the expiry of the License, which allows them to vary. The License may have no expiry, or a different expiry from its Features and Feature Sets. Usually this is not what you want, but it is possible because it enables a variety of Licensing possibilities.

Editing a License

Once you've chosen the Product and click 'Proceed' you are presented with the Edit License Details dialog. How this This dialog appears will differ based on how you defined the Product.

It will always show the information pertinent to the License (Product, Key, Issue Date, Site (for browser-based apps) Expiry Date, and Enabled Flag.

Editing an 'Ala Carte' License

If you have defined Features and/or Feature Sets for your Product, then the right side of the Edit License Details dialog will show either the list of Features, or Feature Sets. You can't mix and match Features and Feature Sets in the same License, so choose one way or the other (or none) when you define your Product.

When you define only Features and no Feature Sets, the Edit License Details dialog shows the Feature list on the right side. All Features are initially disabled and you select and enable those that you wish the License to contain.

When you enable a Feature you may also associate a maximum value with it and optionally set an expiry date for it. Features can only be set to expire at least one day after the issue date and before the License's expiry. For instance, you could have a yearly subscription governed by the License's expiry, and within that,  a six-month trial of a new Feature.

Editing a License with Feature Sets

If you have defined Feature Sets for your Product, you see the Feature Sets list on the right. All the available Feature Sets for this Product and and they are initially disabled; there is a red cross icon beside each one in the list.

Selecting a Feature Set, we see an 'Enabled' check box below the list. Clicking it will enable the selected Feature Set for this License. You may also choose an expiry for the Feature Set which, if set will also apply to all Features inside the Feature Set.

Licensed Feature Sets Must be Mutually Exclusive

A License may contain several Feature Sets but they must be mutually exclusive; that is, they must not contain the overlapping Features.

Zarqon detects this situation and will not allow you to save a license until you correct it. It will disable the 'Done' button and highlight the Feature Set list in red. Hovering over the list will inform you of the conflict as you can see in the screenshot below.

Saving the License Holder

Once you have created all the Licenses for a new License Holder (or modified an existing one), then you can click the 'Save License Holder' button to store the License Holder in your Amazon S3 account.

As with Products, the License Holder will be stored in a protected bucket that only you can access. Additionally, each of the License Holder's Licenses will be encrypted and stored in the publicly readable License bucket, associated with the License Key. When your application validates a license, it reads this public bucket and uses the same License Holder information (name, email address and license key) as entered by the user, to decrypt the license.

Other Manage License Holder Options

Once a License Holder has been saved (or just retrieved and not yet modified) you have the option to Delete the License Holder (and all their Licenses) or to send them email.

Sending Email to the License Holder

Once you've issued a License, the next step you want to take is sending the user an Email. In fact, any time you make a change to a License Holder, you should send them an email from the Zarqon Control Center, so that they have the most relevant details of all their licenses in one place.

Clicking the 'Send Email' button will pop up the Send Email to License Holder dialog. The body of the email will contain a brief salutation with instructions for using the License, followed by a textual representation of the License including all the relevant information.

Sending via the Operating System's Configured Email Client

If you haven't configured an SMTP server, then when you click the 'Send' button, the Zarqon Desktop Control Center sends email to the License Holder using your operating system's configured email client, such as Outlook.

One thing to be aware of with this particular facility is that you should keep your intro as brief as possible, since the email sent using the "MailTo" facility as it is called must be less than 512 characters in length.

Sending via Your SMTP Server

If your SMTP server speaks SMTP or ESMTP but doesn't require SSL / TLS, then the Zarqon Desktop Control Center can log in and send email the same way your operating system's email client does. You can configure this and more about the email that is generated from the Email Configuration Panel, which you can read about in Configuring the Zarqon Control Center.

If you've configured an SMTP Server, then clicking the 'Send' button on the Send Email to License Holder dialog will automatically send the email and keep you updated on its progress as it goes.