[Box Backup] Release Candidate 3

Ben Summers boxbackup@fluffy.co.uk
Sun, 19 Feb 2006 17:55:39 +0000

On 19 Feb 2006, at 17:47, Martin Ebourne wrote:

> On Sun, 2006-02-19 at 17:40 +0000, Chris Wilson wrote:
>> Hi Ben,
>> On Sun, 19 Feb 2006, Ben Summers wrote:
>>> I "broke" backwards compatibility by bumping the protocol number
>>> because...
>>> * A 0.10 server will appear talk to a 0.09 server just fine.
>> Sorry, what I meant was, is there no way that the server can be  
>> made to
>> accept clients with a protocol version older than the highest one it
>> supports, if there are no backwards-incompatible changes in the  
>> protocol,
>> as is the case here?
>> Forcing the server and client protocol versions to match exactly,  
>> while
>> conservative, is a real pain for server operators and users, IMHO.
> I agree that we should try and address this. Really it must be  
> possible
> to upgrade one end without the other. Possibly not either way  
> round, it
> would be ok for instance if the server always had to be >= the client.
> Not sure how the protocol works, but if the client sends its  
> version to
> the server, maybe the server could respond with the same version if  
> and
> only if it can offer compatibility. Otherwise it responds with its own
> version.

There's a Version() command exactly for this. It'll do what we want.

> This doesn't sound like something we can address this time round  
> though.

Writing an automated test for it will be a nightmare! And this will  
really need an automated test because the implications of getting it  
wrong are so bad.