Search term suggestions not available during/after import

[twagoo]

While running an import the suggestion index is not available. A full import usually implies a fairly long time of indexing for the suggester at the end of the import (a few hours even, see #110), during which this problem seems to persist.

Typing search terms leads to an empty suggestion box and the following stack trace in the VLO web app log:

2018-02-09 13:43:11,391 ERROR [org.apache.wicket.DefaultExceptionMapper#mapUnexpectedExceptions:170] - Unexpected error occurred
java.lang.RuntimeException: org.apache.solr.client.solrj.impl.HttpSolrClient$RemoteSolrException: Error from server at http://localhost:8983/solr/vlo-index: Lookup not supported at this time
        at eu.clarin.cmdi.vlo.service.solr.impl.SolrDaoImpl.fireQuery(SolrDaoImpl.java:86)
        at eu.clarin.cmdi.vlo.service.solr.impl.AutoCompleteServiceImpl.getChoices(AutoCompleteServiceImpl.java:43)
...
Caused by: org.apache.solr.client.solrj.impl.HttpSolrClient$RemoteSolrException: Error from server at http://localhost:8983/solr/vlo-index: Lookup not supported at this time
        at org.apache.solr.client.solrj.impl.HttpSolrClient.executeMethod(HttpSolrClient.java:626)
        at org.apache.solr.client.solrj.impl.HttpSolrClient.request(HttpSolrClient.java:253)
        at org.apache.solr.client.solrj.impl.HttpSolrClient.request(HttpSolrClient.java:242)
        at org.apache.solr.client.solrj.SolrRequest.process(SolrRequest.java:178)
        at org.apache.solr.client.solrj.SolrClient.query(SolrClient.java:942)
        at org.apache.solr.client.solrj.SolrClient.query(SolrClient.java:957)
        at eu.clarin.cmdi.vlo.service.solr.impl.SolrDaoImpl.fireQuery(SolrDaoImpl.java:81)
        ... 35 more

Perhaps this can be avoided by adapting the suggestion index creation strategy.

[teckart]

The suggestion index is supposed to be available during rebuild of the index (see for example its reset in the FreeTextSuggester after a completed rebuild). "Lookup not supported at this time" was only reproducable under two circumstances:

• querying the suggester during the first import (i.e. with an uninitialized suggester dictionary), where this is the expected outcome.
• in combination with "external problems" (like full disk during import), where the suggester wasn't available anymore after a forced restart. It remains unclear though why a restart has this consequences.

Closing this ticket as the described error shouldn't occur in a stable environment.