Matthew Toseland schrieb:
> [SimpleFiledSet and Fcp]
>> This is a nasty one: dotted names. It may be easy or not for some
>> languages to deal with
>> this data type. Actually it is easy in python, but doing additional
>> processing based on
>> message signature (like type conversions) is pretty painful and costy.
>> Flat messages
>> shopuld be way easier to handle. Already made a suggestion regarding this...
>>
>
> I really don't understand what the difference is. We provide a Count. If you
> are parsing into a tree structure, it's trivial. Even if you're not, you've
> got the Count, so you can allocate the array before you parse the sub-items.
> Given a multiplexable protocol, using separate messages would mean having an
> identifier in each one which would be just as messy. The only reason to do it
> the way you propose would be to avoid very large messages.
>
From the top of my head, happily breaking everything in the current
protocol
Request
ID=any
Key=any
NItems=N
ReturnCode=N
UserData=any
(...)
End
Item
ID=any
(...)
DataLength=N
ReturnCode=N
UserData=any
End
request = Request(ID='MyRequest')
item = Item(ID='MyRequest/Item1')
---------------------------------------------------------------------------
send request followed by N items, the node will send back request and
item with an error code set
[ID]
hirarchical name used to identify requests and sub-requests. Should
start at connection name
so it is guaranteed each request can be identified uniquely. If apps
feel the need to share
requests, they simply have to share their connection name (though not
recommended, collisions
can not can not be excluded here). Global queue would then be: enumerate
all known
connections / requests with FlagPrivate not set.
[UserData]
(ClientToken as I understood it). Gives clients a uniform way to
associate any data desired to a request.
Pros:
x. no identifier collisions
x. 'flat' mesages (easy to handle)
x. nestable / multiplexable if desired
x. easy to extend
...GetRequestStatus('ConnectionName/MyRequest/MyRequestItem')
x. save for clients. GetRequest('ConnectionName/Request'). Ups ...1M
items, we don't do that.
Cons:
x. still no guarantee that ConnectionName may not collide with another
apps ConnectionName. This will be a risk as long as the node administers
client data.
x. ???
J
