[jira] [Commented] (CASSANDRA-14737) Limit the dependencies used by UDFs/UDAs

["Olivier Michallat (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-14737?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16932719#comment-16932719 ] 

Olivier Michallat commented on CASSANDRA-14737:
-----------------------------------------------

(non-binding) +1 to remove the dependency to the driver.

One indirect consequence of the current situation is that driver types are leaked into UDF implementations. For example, given the following declaration:
{code}
CREATE FUNCTION test.first (t tuple<int,int>) RETURNS NULL ON NULL INPUT RETURNS int LANGUAGE java AS 'return t.getInt(0);';
{code}
The variable {{t}} in the method body is a {{TupleValue}}, a driver type. Same for UDTs.

This is fine as long as Cassandra remains on version 3.x of the driver, but if it upgrades to the latest (4.x), there are a few breaking changes to the API. For example, the getters for temporal types now return {{java.time}} types instead of {{java.util.Date}}. So upgrading the driver would break existing UDF implementations.

Copying the code gives Cassandra full control over the API.

> Limit the dependencies used by UDFs/UDAs
> ----------------------------------------
>
>                 Key: CASSANDRA-14737
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-14737
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Legacy/CQL
>            Reporter: Robert Stupp
>            Assignee: Robert Stupp
>            Priority: Low
>              Labels: UDF
>             Fix For: 4.0
>
>
> In an effort to clean up our hygiene and limit the dependencies used by UDFs/UDAs, I think we should refactor the UDF code parts and remove the dependency to the Java Driver in that area without breaking existing UDFs/UDAs.
>   
> The patch is in [this branch|https://github.com/snazy/cassandra/tree/feature/remove-udf-driver-dep-trunk]. The changes are rather trivial and provide 100% backwards compatibility for existing UDFs.
>   
>  The prototype copies the necessary parts from the Java Driver into the C* source tree to {{org.apache.cassandra.cql3.functions.types}} and adopts its usages - i.e. UDF/UDA code plus {{CQLSSTableWriter}} + {{StressCQLSSTableWriter}}. The latter two classes have a reference to UDF's {{UDHelper}} and had to be changed as well.
>   
>  Some functionality, like type parsing & handling, is duplicated in the code base with this prototype - once in the "current" source tree and once for UDFs. However, unifying the code paths is not trivial, since the UDF sandbox prohibits the use of internal classes (direct and likely indirect dependencies).
>   
>  /cc [~jbellis] 
>   



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org