Live update

Comentario supports the so-called Live update — a mechanism that delivers new or updated comments on the page that is already open, without the need to reload the page.

WebSocket connections

The Live update mechanism is built upon the WebSocket technology supported by all modern browsers. It allows for two-way communication between the server and the browser.

Comentario utilizes WebSocket connections for delivering comment updates directly into the browser, almost instantaneously.

It supports almost all applicable comment changes:

• New comment is added;
• Comment text is updated;
• Comment is deleted;
• Comment is approved or rejected by a moderator;
• Comment is (un)stickied.

Page- and domain-wide changes (such as domain operations) are not (yet) supported by Live update.

Settings

The Live update mechanism is controlled by two settings:

• Globally via a static config item. It’s on, unless --no-live-update is passed on the command line.
• On every page via the live-update attribute of the comments tag. Again, it’s on by default.

Additionally, Comentario administrator can limit the number of simultaneous WebSocket connections to prevent server memory exhaustion by specifying the --ws-max-clients command-line option. Its default value is 10000.

Clients trying to connect in excess of the imposed limit won’t be able to use Live update, but will otherwise operate exactly the same way.