This uses an enhanced version of the Nutch/Solr TextProfileSignatue.
As a result, a signature of the document is written to the solr search
index. Additionally for each time when a signature is written, it is
checked if the singature exists already in the index. If the signature
does not exist, the document is marked as unique. The unique attribute
can now be used to sort document lists and bring duplicates to the end
of a result list.
To enable this, a large portion of the search api to Solr had to be
changed. This affected mainly caching of 'exists' searches to enhance
the check for existing signatures and do this without actually doing a
solr query.
Because here the first time a long number is used as value in the Solr
store, also the value naming in the YaCySchema had to be adopted and
normalized. This caused that many files had to be changed.
need regular expressions as search attributes. They had now been removed
from the advanced search page while they are still created internally.
The filter is then expressed against solr as regular expression filter
query. If the expression points out a selection of an specific protocol,
host or filetype this is then translated into a facetted query.
added solr highlighting / YaCy snippets to YaCy search results
- facets are now much more complete
- facets are computed and searched much faster
- snippet computation is done by solr if solr knows the snippet
URIMetadataNode which creates the opportunity to access Solr objects
directly and use their information richness
- lazy initialization of the URIMetadataNode object - should cause less
computation and memory usage during search.
- removed dead code
MultiProtocolURI during normalform computation because that should
always be done and also be done during initialization of the
MultiProtocolURI Object. The new normalform method takes only one
argument which should be 'true' unless you know exactly what you are
doing.
- reduced danger that a non-existing RWI database causes NPEs
- added Solr queries to did-you-mean: this makes it possible that our
did-you-mean algorithm works together with only Solr and without RWIs
the segments had been there to create a tenant-infrastructure but were
never be used since that was all much too complex. There will be a
replacement using a solr navigation using a segment field in the search
index.
- vocabulary annotation is not done any more into the metadata of urldb
- vocabularies are written into the jena triplestore using a rdf
vocabulary
- vocabularies for rdf tripel must be updated; refactoring done
- with the new navigation tags in the triplestore a faster
pre-urldb-lookup is possible: navigation is processed now within the RWI
during pre-ranking retrieval
- added also a Owl vocabulary stub to add the plain-text url to the
triplestore using the owl:sameas predicate
this causes that the table is not initialized when there is no search is
done. the effect is most strong if YaCy is started headless which causes
no browser pop-up which otherwise would load the search page and
therefore trigger the initialization of the table.
Michael Peter Christen