ietf-nntp MODE STREAM response

[Jim Calvin]

>Jim Calvin wrote:
>> The current draft (draft-ietf-nntpext-imp-03.txt) lists the following
>> responses for MODE STREAM:
>>
>> 1.2.1.	Responses
>>
>>    203 Streaming is OK
>>    500 Command not understood
>>
>> I propose a third response be added to the list:
>>
>>    400 not accepting articles

<snip>

To which Jeff Garzik, responded:

>This seems redundant, because MODE STREAM is issued immediately
>following the server's initial response code (200 feeding ok, 502 access
>denied, etc.)
>
>If a server can return 400 at the MODE STREAM stage, it is extremely
>likely that it can return 400 at the connection stage as well.

Well, 40x/50x could be an inappropriate response to a general peer/client 
at the connection stage. For example, if the peer/client only intended to 
read articles, that's probably ok; even with the full disk.

However, you might then argue that 201 would be the proper connection 
response to signal this situation. But does that reasonably distinguish 
between, "you can't post in general" as opposed to "you can't post right 
now for some transient reason?"

MODE STREAM signals a new intent on the part of the peer. That seems like 
reasonable point for a server make such a decision and issue a 400 response.
Jim