Subscription Configuration

Silva has a finely grained subscription feature. Subscriptions allow visitors to subscribe and receive email notifications of updates to a page, a folder, or a publication on the site. The Silva Manager must activate the subscription feature for the site. Editors can then choose to enable subscription functionality for some or all of their content.

Adding a Subscription Service
In the ZMI go to the Services tab and add a Silva Subscription Service from the drop-down (Fig. 1).

Adding a Silva Subscription Service
Fig. 1. Adding a Silva Subscriptions Service.

Activating a service subscription
The Manager can enable or disable the subscriptions feature for the whole Silva site in the ZMI, under the services tab in service_subscriptions (Subscription Service).
Click the Activate button to enable the subscriptions service (Fig. 2.).

Activating the subscriptions service
Fig. 2. Activating the subscriptions service.

The email templates that are used for creating the email notifications used by the subscription service are found in the service_subscriptions content tab. You can configure variable in the form (Fig. 3).

Configuring the subscriptions service
Fig. 3. Subscriptions service configuration form

The site administrator can also choose to create an instance of the MaildropHost object for more efficient email handling.

Using the MaildropHost Product
If the MaildropHost Product is not installed, the subscription extension will use the MailHost Product that is distributed with Zope.

The MailHost will send email ‘synchronously’, meaning, the calling code will have to wait for the email delivery to complete. This can potentially cause huge slowdowns.

To overcome this issue it is highly recommended to use the MaildropHost replacement product, which uses a spool based mechanism for sending the email. Whenever an email needs to be sent, it’s written to a temporary file in a spool directory on the filesystem. A separate delivery process (independent from the Zope processes) will poll the spool directory and deliver the emails using the settings as configured in the ‘’ file for this Product. See the MaildropHost Product’s README.txt for details.

The MaildropHost Product can be found here:

The Silva Subscriptions feature needs MaildropHost version 1.9 or higher.

See also Subscription management:
Subscriptions Services Editor Tasks