[ 
https://issues.apache.org/jira/browse/CASSANDRA-9193?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14503098#comment-14503098
 ] 

Matt Stump commented on CASSANDRA-9193:
---------------------------------------

The above example demonstrates the serialized partition key dilemma pretty 
well. A {{ReadCommand}} has ByteBuffer for key, which can be a serialized 
composite. I suppose I could provide a function that given a CFMetaData and a 
key byte buffer return an array of java objects to JS, one object per key 
component.

> Facility to write dynamic code to selectively trigger trace or log for queries
> ------------------------------------------------------------------------------
>
>                 Key: CASSANDRA-9193
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-9193
>             Project: Cassandra
>          Issue Type: New Feature
>            Reporter: Matt Stump
>
> I want the equivalent of dtrace for Cassandra. I want the ability to 
> intercept a query with a dynamic script (assume JS) and based on logic in 
> that script trigger the statement for trace or logging. 
> Examples 
> - Trace only INSERT statements to a particular CF. 
> - Trace statements for a particular partition or consistency level.
> - Log statements that fail to reach the desired consistency for read or write.
> - Log If the request size for read or write exceeds some threshold
> At some point in the future it would be helpful to also do things such as log 
> partitions greater than X bytes or Z cells when performing compaction. 
> Essentially be able to inject custom code dynamically without a reboot to the 
> different stages of C*. 
> The code should be executed synchronously as part of the monitored task, but 
> we should provide the ability to log or execute CQL asynchronously from the 
> provided API.
> Further down the line we could use this functionality to modify/rewrite 
> requests or tasks dynamically.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to