[jira] [Created] (SOLR-9918) An UpdateRequestProcessor to skip duplicate inserts and ignore updates to missing docs

["Tim Owen (JIRA)" <ji...@apache.org>]

Tim Owen created SOLR-9918:
------------------------------

             Summary: An UpdateRequestProcessor to skip duplicate inserts and ignore updates to missing docs
                 Key: SOLR-9918
                 URL: https://issues.apache.org/jira/browse/SOLR-9918
             Project: Solr
          Issue Type: Improvement
      Security Level: Public (Default Security Level. Issues are Public)
          Components: update
            Reporter: Tim Owen


This is an UpdateRequestProcessor and Factory that we have been using in production, to handle 2 common cases that were awkward to achieve using the existing update pipeline and current processor classes:

* When inserting document(s), if some already exist then quietly skip the new document inserts - do not churn the index by replacing the existing documents and do not throw a noisy exception that breaks the batch of inserts. By analogy with SQL, {{insert if not exists}}. In our use-case, multiple application instances can (rarely) process the same input so it's easier for us to de-dupe these at Solr insert time than to funnel them into a global ordered queue first.
* When applying AtomicUpdate documents, if a document being updated does not exist, quietly do nothing - do not create a new partially-populated document and do not throw a noisy exception about missing required fields. By analogy with SQL, {{update where id = ..}}. Our use-case relies on this because we apply updates optimistically and have best-effort knowledge about what documents will exist, so it's easiest to skip the updates (in the same way a Database would).

I would have kept this in our own package hierarchy but it relies on some package-scoped methods, and seems like it could be useful to others if they choose to configure it. Some bits of the code were borrowed from {{DocBasedVersionConstraintsProcessorFactory}}.

Attached patch has unit tests to confirm the behaviour.

This class can be used by configuring solrconfig.xml like so..

{noformat}
  <updateRequestProcessorChain name="skipexisting">
    <processor class="solr.LogUpdateProcessorFactory" />
    <processor class="org.apache.solr.update.processor.SkipExistingDocumentsProcessorFactory">
      <bool name="skipInsertIfExists">true</bool>
      <bool name="skipUpdateIfMissing">false</bool> <!-- We will override this per-request -->
    </processor>
    <processor class="solr.DistributedUpdateProcessorFactory" />
    <processor class="solr.RunUpdateProcessorFactory" />
  </updateRequestProcessorChain>
{noformat}

and initParams defaults of

{noformat}
      <str name="update.chain">skipexisting</str>
{noformat}




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

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