Renewing the Vaadin License Checker

Artur Signell
Artur Signell
On Sep 20, 2022 3:42:22 PM

For those using one of our commercial products, you may have encountered the license validation window at some point:

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When you click on it or log in to to verify your identity, the system is notified that everything is okay, and it goes away, allowing you to continue building your app.

Sometimes, the notification does not go away even though everything is fine. Why does this happen? 

It is primarily based on third-party cookies, which browsers are increasingly selective about. Additionally, if you use ad blockers or similar software, the license check may be misinterpreted as an advertisement.

Making it more robust

As a way of resolving issues with ad blockers and third-party cookies, we have updated the license checker so that it doesn't have to rely on cookies. Instead, it stores a file with the licensing data on your device and deploys it during validation processes. Hence, there will be no interruption to successful checking from your browser.

Production builds

Previously, the checker was only engaged purely during development on the local machine, but you should be aware that it is now also activated during a production build. 

This is how it used to be in Vaadin 8 but it differs from platform versions 10+. You now have to ensure that your CI server has access to a server license key. You can download a server license key (an `offlineKey` file) from that you can then place in the home directory of your CI server.

The same installed license file will be automatically used for local production builds.

Read documentation

Offline usage

In situations where your development environment is not able to build a connection to our license server, you'll be required to install an offline license on your machine. An offline license key can be downloaded from by entering the ID of your development machine. There is additional information on the page where this machine ID is displayed.

Once downloaded, transfer the license file to the development machine, and the offline development will start functioning. However, note that the license is tied to one machine, so you need to create multiple offline licenses if you are working on multiple machines.

Read documentation

Available in Vaadin 23.2 by default

The new license checker is available in 23.2 by default. However, we all know software can contain bugs, and a license checker is no different. So if you encounter any problem, please report it, and we will fix it.

Artur Signell
Artur Signell
Artur Signell works as CTO at Vaadin. He earlier lead the Vaadin products team and was responsible for all Vaadin products. Currently he is focusing on technology and research.
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