[ 
https://issues.apache.org/jira/browse/HBASE-9681?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13788309#comment-13788309
 ] 

stack commented on HBASE-9681:
------------------------------

Is this over-engineering? What if we have it that server never drops support 
for any one codec (at least, within major versions).  Then there is no need of 
negotiation?  Client just says what they want?  Server fails connection if 
can't give client want it wants.  I'm guessing client doesn't want 'fallback'.  
If it does, it can do it itself by catching the UnsupportedCodecException and 
then go again w/ a different codec. See 'J.4.3.1. CellBlock Codecs' in 
http://hbase.apache.org/book.html#d0e14417  

> Basic codec negotiation
> -----------------------
>
>                 Key: HBASE-9681
>                 URL: https://issues.apache.org/jira/browse/HBASE-9681
>             Project: HBase
>          Issue Type: Sub-task
>    Affects Versions: 0.98.0
>            Reporter: Andrew Purtell
>
> Basic codec negotiation:
> There should be a default codec used for cell encoding over the RPC 
> connection. This should be configurable in the site file. 
> The client can optionally send a message, a manufactured "call" that would 
> otherwise be invalid in some way, to the server asking for a list of 
> supported cell codecs. An older server should simply send back an error 
> because the request is invalid except to servers supporting this feature. A 
> server supporting this feature should send back the requested information or 
> an error indication if something went wrong.
> The client can optionally send a message, a manufactured "call" that would 
> otherwise be invalid in some way, to the server asking for it to use a given 
> codec for all further communication. Otherwise the server will continue to 
> use the default codec. The server will send back a call response 
> acknowledging the change or an error indication if the request cannot be 
> honored.
> Server configuration should support mappings from one codec type to another. 
> We need to handle the case where the server has a codec available that 
> extends the requested type but overrides some behavior in the base class, and 
> this is what should be used in lieu of the base type. It must also be 
> possible to choose an alternate default codec which stands in for the default 
> codec, is compatible with client expectations, but changes the server side 
> behavior as needed in the absence of negotiation. 



--
This message was sent by Atlassian JIRA
(v6.1#6144)

Reply via email to