Licensing and evaluation Leave feedback

To explore the system effectively, you may want immediate access to the API. GroupDocs.Watermark simplifies this by offering various purchase plans, along with a Free Trial and a 30-day Temporary License for evaluation.

Note

To learn more about licensing options, purchasing, and evaluation policies, refer to the Purchase Policies and FAQ section.

After purchasing GroupDocs.Watermark for Python via .NET, you will receive a license file that unlocks the full functionality of the API. A few rules apply:

• Apply the license only once per process, in your start-up code.
• Apply it before constructing any Watermarker or other GroupDocs.Watermark object.
• A license can be applied from a file path, from a binary stream (handy when the license is an embedded resource), or as a Metered License that bills by usage.

Use the set_license method to license the component. Calling it more than once is harmless — it simply wastes a little processor time.

The example below applies a license from a file path. It reads the path from the GROUPDOCS_LIC_PATH environment variable and falls back to a local GroupDocs.Watermark.lic file:

import os
from groupdocs.watermark import License

def set_license_from_file():
    # Resolve the license path from the environment, with a local fallback
    license_path = os.environ.get("GROUPDOCS_LIC_PATH", "./GroupDocs.Watermark.lic")

    # Apply the license before using any watermarking features
    if os.path.exists(license_path):
        License().set_license(license_path)
        print("License set successfully.")
    else:
        print("License file not found. Running in evaluation mode.")

if __name__ == "__main__":
    set_license_from_file()

You can also apply a license from any readable binary stream — useful when the license ships as an embedded resource:

import os
from groupdocs.watermark import License

def set_license_from_stream():
    # Resolve the license path from the environment, with a local fallback
    license_path = os.environ.get("GROUPDOCS_LIC_PATH", "./GroupDocs.Watermark.lic")

    # Apply the license from an open binary stream
    if os.path.exists(license_path):
        with open(license_path, "rb") as stream:
            License().set_license(stream)
        print("License set successfully.")
    else:
        print("License file not found. Running in evaluation mode.")

if __name__ == "__main__":
    set_license_from_stream()

A Metered License lets you pay for what you use. Set the public and private keys with set_metered_key before using the API:

from groupdocs.watermark import Metered

def set_metered_license():
    # Replace these placeholders with your real metered public/private keys
    public_key = "*****"
    private_key = "*****"

    # Skip the call until real keys are supplied (placeholder keys are rejected)
    if "*" in public_key or "*" in private_key:
        print("Provide real metered keys to enable metered licensing.")
        return

    # Apply the metered keys before using any watermarking features
    Metered().set_metered_key(public_key, private_key)
    print("Metered license set successfully.")

if __name__ == "__main__":
    set_metered_license()

You are not required to keep the license file name as GroupDocs.Watermark.lic. You can rename it to any preferred name and use that name when applying the license in your application.

When you download the license from the GroupDocs website it is saved as GroupDocs.Watermark.lic. However, some web browsers may automatically append .xml, resulting in GroupDocs.Watermark.lic.xml.

If your Windows settings are configured to hide file extensions (the default), the file may still appear as GroupDocs.Watermark.lic in File Explorer even though the actual name is GroupDocs.Watermark.lic.xml. This discrepancy can cause set_license to throw an exception. To fix it, manually rename the file to remove the .xml extension, or disable “Hide extensions for known file types” in Windows.

You can evaluate GroupDocs.Watermark for Python via .NET without purchasing a license by using one of the following options.

The evaluation version is identical to the purchased one; it becomes fully licensed once you set a license. Without a license the Free Trial gives you access to the API’s features, but with some limitations:

• A maximum of 10 documents can be loaded per application run.
• Only one watermark can be added to a document per editing session.
• The output document carries an evaluation watermark stamp.

To experience the complete features of GroupDocs.Watermark without the limitations of the Free Trial, you can request a 30-day “Temporary License”.