RESOLVED - com.ibm.wsspi.webcontainer.util.RequestUtils parseQueryString SRVE0325E: Exceeding maximum parameters allowed per request 10,000 ,current 10,000 , cannot add more.(SOLR)

Sometimes , you may find that the SOLR Search and Browse cease to function and you may keep hitting "No Search Results". On further investigating the SOLR logs , you may find the below exceptions -

[5/26/15 11:27:08:586 BST] 00000027 SolrCore      I org.apache.solr.core.SolrCore execute [MC_10001_CatalogEntry_en_GB] webapp=/solr path=/select params={q=shortDescription:tv} hits=905 status=0 QTime=1

[5/26/15 11:27:36:127 BST] 00000027 util          E com.ibm.wsspi.webcontainer.util.RequestUtils parseQueryString SRVE0325E: Exceeding maximum parameters allowed per request 10,000 ,current 10,000 , cannot add more.

[5/26/15 11:27:36:131 BST] 00000027 SolrDispatchF E org.apache.solr.common.SolrException log java.lang.IllegalArgumentException

        at com.ibm.wsspi.webcontainer.util.RequestUtils.parseQueryString(RequestUtils.java:196)

        at com.ibm.ws.webcontainer.servlet.RequestUtils.parsePostData(RequestUtils.java:356)

        at com.ibm.ws.webcontainer.srt.SRTServletRequest.parseParameters(SRTServletRequest.java:2051)

        at com.ibm.ws.webcontainer.srt.SRTServletRequest.getParameterMap(SRTServletRequest.java:2568)

        at org.apache.solr.request.ServletSolrParams.<init>(ServletSolrParams.java:29)

        at org.apache.solr.servlet.StandardRequestParser.parseParamsAndFillStreams(SolrRequestParsers.java:394)

        at org.apache.solr.servlet.SolrRequestParsers.parse(SolrRequestParsers.java:115)

        at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:223)

        at com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:190)

        at com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:125)

        at com.ibm.ws.webcontainer.filter.WebAppFilterChain._doFilter(WebAppFilterChain.java:80)

        at com.ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter(WebAppFilterManager.java:908)

        at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:935)

        at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:503)

        at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest

This is caused when the SOLR query string has more than 10,000 query string parameters. SOLR cannot handle that and fails with an internal server error. To resolve this issue , please follow the below steps -

1. In the administrative console click 
Servers > Application Servers > server_name > Web Container settings > Web Container 

2. Under Additional Properties select Custom Properties. And add a new 

Property name: com.ibm.ws.webcontainer.maxParamPerRequest 

Value : some number 

The default value for this is 10000. You can set it a different number or you can set this property to -1 if you do not want to limit the number of parameters that can be included in a request
 

WC Search Customization Points

A simple Mind map which depicts the commonly customized files/components with their purpose while extending the WC Search.

SearchPreProcessor
A query preprocessor modifies the native SolrQuery object right before it is sent to the Solr server for processing.

The custom query preprocessor needs to be mapped in the wc-search.xml.

For more details , refer to the infocenter link

SearchPostProcessor
A query postprocessor modifies the physical DataObject, SolrEntityContainerImpl, immediately after the QueryResponse is returned from the Solr server.

The custom query postprocessor needs to be mapped in the wc-search.xml

For more details , refer the infocenter link 

SearchProfile
WebSphere Commerce search uses search profiles to control the storefront search experience at a page-level. Search profiles group sets of search runtime parameters such as search index name, search index fields, expression providers and result filters, paging and sorting, and search feature configurations such as text highlighting, facets, and spelling correction. Search profiles are defined in the WebSphere Commerce search configuration file (wc-search.xml). 

For more details , refer the infocenter link 

Business Object Mediator
The business object mediator maps physical search index fields to their corresponding logical fields in the CatalogEntryView noun. Custom physical index fields can be mapped by using the UserData fields.

For more details , refer the infocenter link 

Preprocessor and Data Import Handler (DIH)
The preprocessing tasks are controlled by the wc-dataimport-preprocess XML files. The files contain table definitions, database schema metadata, and references to the Java classes used in the preprocessing steps. Those files are invoked by the di-preprocess utility, which extracts and flattens WebSphere Commerce data and then outputs the data into a set of temporary tables inside the WebSphere Commerce database. The data in the temporary tables is then used by the index building utility to populate the data into Solr indexes using Solr's Data Import Handler (DIH). 

For more details , refer the infocenter link

Search Schema
Typically, WebSphere Commerce data is stored in a relational database. In WebSphere Commerce search, another repository also stores WebSphere Commerce data. That is, the product information is stored in a search index for searching purposes. Most of the data that are stored in the search index is extracted from the relational database. Similar to the database schema, the search index also contains a schema. The fields that are defined in this schema are used by WebSphere Commerce search.
By customizing the schema.xml , we define fields in the search schema that store the data to be searched. Once the new fields are defined, the mappings must be configured for the fields to the database schema.

For more details , refer the infocenter link

I hope you will find the mindmap really useful. As always , please feel free to add your comments and suggestions.

Commerce Composer in a Nutshell

A excellent video to learn about the amazing Commerce Composer tool - which enables business to create new pages without IT assistance. Available FEP7 and above.

Not only does it allow the business to control - how the page looks but also enables them to add SEO metadata contents for improved search capabilities and associate search terms which lead to the display of the page.

 http://www-01.ibm.com/support/knowledgecenter/SSZLC2_7.0.0/com.ibm.commerce.management-center.doc/demo/PageComp/PageComp.html