Re: [PATCH] Describing depth/recurse concepts in the RA layer

Karl Fogel wrote:
> "C. Michael Pilato" <cmpilato@collab.net> writes:
>> PRE-1.5 CLIENTS
>>
>> Pre-1.5 clients will never transmit reported depths and never
>> transmit a requested depth. But they will (perhaps optionally,
>> depending on the RA layer) transmit a requested recurse (either
>> 'yes' or 'no', with 'yes' being the default).
>>
>> When speaking to a pre-1.5 server, what happens happens. It's the past,
>> man -- you don't get to define it now.
>>
>> When speaking to a 1.5 server, the not-reported depths are treated
>> like reported depths of 'infinity', and the recurse 'yes' and 'no'
>> map to depths of 'infinity' and 'files', respectively.
>
> Amen to all that.
>
>> 1.5 CLIENTS
>>
>> 1.5 clients will transmit reported depths (with 'infinity' as the
>> default) and will transmit a requested depth (with 'unknown' as the
>> default). They will also -- for the sake of older, non-depth-aware
>> servers -- transmit a requested recurse, mapped from requested
>> depths ('empty' or 'files' = no; 'unknown', 'immediates', and
>> 'infinity' = yes).
>
> When a 1.5 client has no requested depth, does it still transmit
> recurse=yes in those RA layers that today transmit recurse=yes by
> default?

I dunno -- I was trying to imply by noting the presence of default values
that the info was *effectively* transmitted (insomuch as "not transmitting
recurse=no" is effectively the same as transmitting recurse=yes) more so
than that the protocol contained literal embeddings of these values. Maybe
I should make that more clear.

>> When speaking to a pre-1.5 server, the requested recurse is the only thing
>> the server notes, but is obviously more "grainy" than the depth concept.
>> The client, therefore, must filter out unwanted data that the server
>> transmits.
>>
>> When speaking to a 1.5 server, the requested recurse is ignored. A
>> requested depth of "unknown" means "only send information about the
>> stuff in my report, depth-aware-ily". Other depths are honored by
>> the server properly, and the client must handle the transformation of
>> any working copy depths from their pre-update to their post-update
>> depths and content.
>
> Say "Other requested depths are honored by the server properly..."
> ^^^^^^^^^
> ...just to be clear :-).

Heheh. Yes! +1 on clarity (since that is, after all, the point of the
exercise).

> This whole last paragraph looks correct to me, but the meaning of the
> first sentence might be clearer if expanded to this:
>
> "When a 1.5 server receives both requested depth and recurse, the
> recurse is ignored in favor of the depth, even when the depth is
> svn_depth_unknown. But when a 1.5 server receives recurse with no
> requested depth, it honors the recurse, on the theory that it's
> talking to a pre-1.5 client."
>
> (You've sort of organized your text around the client version, but we
> really need to talk about server behavior in detail for the reader to
> fully grok what's going on, IMHO.)

Okay. I think this ties into the fact that I was talking more about the
implicit data transfer than the literal. But I agree that there is value in
recording how the literal gets translated into the effective.

I'll adjust and commit, and review/adjustment can be made on the committed
stuffs.

-- 
C. Michael Pilato <cmpilato@collab.net>
CollabNet   <>   www.collab.net   <>   Distributed Development On Demand