Allow servers to give clients a MOTD

[Andrew Bennetts]

Sometimes a server administrator would like to a way to display a message to users of a service. For example:

    This server will be down for planned maintenance in 2 hours time for approximately 15 minutes.

Or:

    Please update your branches to point to $NEW_URL, because we are switching to a new hosting provider.

Or:

    Please make sure you are using bzr+ssh:// URLs, as sftp:// access will be disabled from yyyy-mm-dd.

Currently there is no facility in Bazaar to do this. It would be nice if at least the smart server protocol supported fetching and displaying a MOTD like these.

To an extent this can be worked around by just sending emails to all users of a service, but a MOTD that is displayed when you are actually using the service is more likely to be noticed. (On the other hand, a server that always displayed a 40-line MOTD on every connect would be annoying! I'm not sure how to balance that concern.)

[John A Meinel (jameinel)]

I believe Darcs has explicit support for this as part of connecting to a branch. So it will tell you short details. One very helpful one is "This branch is no longer maintained, go over here". But that is more a per-branch thing, than a site-wide one.

Note that if you are using SSH as your connection (bzr+ssh:// or sftp://) you already have a MOTD ability. I don't know how they set it up, but one of my branches has a 40-line "Connecting to this server means you are accepting these terms. If you do not accept them, disconnect immediately, blah blah blah).

It is generally very annoying, but it makes it obvious when we connect multiple times :).

So mostly, I think this could be handled at a different layer, though it may be that:

a) Paramiko won't display these messages (I'm sure OpenSSH does)
b) We don't have a way to do it for HTTP
c) It might be easier to set it for a single branch/versus the whole site.