C++ SDK Configuration and Usage
C++ SDK allows implementing licensing in two ways: - using the License and LicenseManager classes; - using the LicenseHandler class.
LicenseHandler encapsulates License and LicenseManager functionality. By default, it is exceptions-free, but you can enable exceptions. It's up to you whether to use LicenseManager and License directly or use this class. LicenseHandler is also useful for Unreal Engine clients because it is free of memory access violation problems due to runtime conflicts with UE.
This article has code samples for both approaches. In the other ones, we will demonstrate SDK usage only with LicenseManager and License. LicenseHandler class has methods corresponding to License/LicenseManager functionality.
See also our Error Handling tutorial.
To initialize the SDK you will need to fill in your application name and version, LicenseSpring API key, shared key and product code.
Both the API key and shared key can be found on your LicenseSpring account under Settings->Keys:
Your product code is located in your product list under Configure Products:
Please, keep in mind that the product code field is case-sensitive.
When you have the necessary values, create the configuration.
Now you can initialize LicenseManager or LicenseHandler using this configuration object.
The license keys are located in Licenses section:
To implement user-based licensing please refer to: User-Based Licensing.
To activate a license, create a LicenseID using the given key and call activation method.
The process of activating a license refers to binding a device to a license. On the LicenseSpring platform, activating the license increments the total activations counter within the license.
The local license is a copy of the license information that is saved on the end user's local computer. Users who have not activated the license on their end before will not have a local license. By default, the local license is stored: %USERPROFILE%\AppData\Local\LicenseSpring\”Product Code”\License.key.
See Local License File for more information.
If a device already has a license, and you try to activate another license on that device, for the same product, that newly activated license will override the existing license, deleting it from the device. This will be on the developer to make sure that they check if a license exists on the device before a new activation:
It is recommended to perform a local license check at application start to confirm that the local license file belongs to the current device and has not been transferred.
It is also useful to check whether the local license file has been tampered with and whether the local license is still valid.
The local check can produce the following errors:
License is in invalid state (disabled, epired or inactive)
License does not belong to configured product
License does not belong to current device
Detected cheating with system clock
Online license check refreshes the local license with the data from LicenseSpring backend:
The online check can produce the following errors:
License is disabled, was reset or expired
License does not belong to current device or the device was blacklisted
Connection-related errors: if there's no Internet or an internal server error occured.
This method also returns the most recent InstallationFile available for the license which can be useful for managing software updates.
For more information about managing software updates, see Handling Product Versions.
You can also check for active, valid, enabled, and expired licenses using isActive, isValid, isEnabled, and isExpired methods respectively.
Note that an active license does not necessarily mean a license is valid. A valid license means the license is active, enabled, and not expired. An active license means that the license is bound to a device, but may also be disabled or expired.
Below you can find a code sample that initializes the SDK, retrieves a local license or activates a new one, and performs the necessary checks.
Deactivating a license unbinds the device from the license, and decrements the number of total activations. Depending on the license transfer policy, this usually means that the license is freed up to be activated onto a new device. Deactivating is done using the following method:
The License::deactivate() method allows to specify whether you want to remove the local license file after the deactivation. Set the removeLocalData parameter to true if you want the local files to be removed.