lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Per Steffensen (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (SOLR-3382) Finegrained error propagation (focus on multi-document updates)
Date Wed, 10 Apr 2013 08:28:16 GMT

    [ https://issues.apache.org/jira/browse/SOLR-3382?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13627601#comment-13627601
] 

Per Steffensen commented on SOLR-3382:
--------------------------------------

We use this Apache issue/ticket to keep track of what we did on our own internal version of
Solr, and what would be provided in a patch for this issue if the Apache community was interested.
Therefore this additional comment, for now just a "note to self":

The solution for "error propagation" now not only supports sending error-code, error-msg and
error-type (corresponding to package+classname in java) so that exceptions can be reconstructed
and thrown on client-side (automatic in SolrJ). Now it also supports additional properties
(name/value pairs) on an exception and have those propagated over the line to the client where
it can be (will be in SolrJ) attached as properties on the reconstructed exception. Explicit
properties on exception are nice, because only alternative is to "encode" it in the error-msg,
and then you have to parse the error-msg on the receiving side and that is part of what we
want to avoid (it is too hacky and error prone).
Properties also supported on "nested" exceptions about parts of the request-handling that
failed - e.g. in a 5-doc update-request, where 3 updates succeed and 2 fail, 2 "nested/part"-exceptions
will be returned to the client. Both of those "nested/part"-exceptions can independently contain
their own set of properties.

As a proof-of-concept and to show that the implementation works and to have the feature "protected"
by tests, the VersionConflict exception introduced in the solution for SOLR-3178 has been
enhanced to carry a property "currentVersion" containing the current version of the document
on server-side. So now, if the client want to know about the actual current version on server-side,
it does not have to parse the error-msg to get hold of it - just read the provided property.
All existing tests using VersionConflict has been updated to test that the returned currentVersion
is correct. There are test that have VersionConflict as the top-level exception (version-conflict
in a single-doc update-request) and other tests that have several VersionConflicts as "nested/part"-exceptions
so both aspects are tested. 
                
> Finegrained error propagation (focus on multi-document updates)
> ---------------------------------------------------------------
>
>                 Key: SOLR-3382
>                 URL: https://issues.apache.org/jira/browse/SOLR-3382
>             Project: Solr
>          Issue Type: New Feature
>          Components: clients - java, Response Writers, update
>    Affects Versions: 3.5
>            Reporter: Per Steffensen
>            Assignee: Per Steffensen
>              Labels: client, documents, error, multiple, propagation, update
>             Fix For: 4.3
>
>
> Today when an error occurs on server side during the handling of a request, the handling
of the request will stop at the point when the error occured, and only a error-message (reason
part of HTTP status line) and error-code (HTTP response code) is pushed back to the sender
of the request.
> This can be improved in several ways
> - Reacting as a client on errors, solely based on a textual message and a HTTP response
code is hard. The error ought have some kind of type telling the client which kind of error
happened.
> - When handling multi-document updates the error might happen during the handling of
one of the documents - potentially not the first document and potentially not the last document.
> -- The client ought to get information about which documents where successfully updated
(the ones comming before the document creating the error).
> -- If the error updating a document is not due to a general problem, it could very well
be that some of the documents not yet handled at the time of the error (the documents comming
after the document creating the error), could be successfully updated - so why not try that.
> -- If continuing the updating of documents, even after one document-update resulted in
an error (as suggested above), the updating of some of those documents might also result in
an error. This leads to another improvement, namely being able to send information about more
than one error back to the client.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org


Mime
View raw message