attribute in the <a> tag for each crawl. This introduces a lot of
changes because it extends the usage of the AnchorURL Object type which
now also has a different toString method that the underlying
DigestURL.toString. It is therefore not advised to use .toString at all
for urls, just just toNormalform(false) instead.
instead of TreeMaps)
- enhanced memory footprint of database indexes (by introduction of
optimize calls)
- optimize calls shrink the amount of used memory for index sets if they
are not changed afterwards any more
- replaced load failure logging by information which is stored in Solr
- fixed a bug with crawling of feeds: added must-match pattern
application to feed urls to filter out such urls which shall not be in a
wanted domain
- delegatedURLs, which also used ZURLs are now temporary objects in
memory
for anchor attributes.
- this caused that large portions of the parser code had to be adopted
as well
- added a counter target_order_i for anchor links in webgraph
computation
all unique links! This made it necessary, that a large portion of the
parser and link processing classes must be adopted to carry a different
type of link collection which carry a property attribute which are
attached to web anchors.
- introduction of a new URL class, AnchorURL
- the other url classes, DigestURI and MultiProtocolURI had been renamed
and refactored to fit into a new document package schema, document.id
- cleanup of net.yacy.cora.document package and refactoring
in intranets and the internet can now choose to appear as Googlebot.
This is an essential necessity to be able to compete in the field of
commercial search appliances, since most web pages are these days
optimized only for Google and no other search platform any more. All
commercial search engine providers have a built-in fake-Google User
Agent to be able to get the same search index as Google can do. Without
the resistance against obeying to robots.txt in this case, no
competition is possible any more. YaCy will always obey the robots.txt
when it is used for crawling the web in a peer-to-peer network, but to
establish a Search Appliance (like a Google Search Appliance, GSA) it is
necessary to be able to behave exactly like a Google crawler.
With this change, you will be able to switch the user agent when portal
or intranet mode is selected on per-crawl-start basis. Every crawl start
can have a different user agent.
jdk-based logger tend to block
at java.util.logging.Logger.log(Logger.java:476) in concurrent
environments. This makes logging a main performance issue. To overcome
this problem, this is a add-on to jdk logging to put log entries on a
concurrent message queue and log the messages one by one using a
separate process.
- FTPClient uses the concurrent logging instead of the log4j logger
adjusted to smaller and 1-core devices.
- the workflow processor now starts no process at all. these are started
as soon as parser/condenser/indexing queues are filled.
- better abstraction
- an existing ranking servlet for solr was extended. It is now possible
to set boost values for fields, boost functions and boost queries.
- The ranking can have different instances, but currently only the first
one is used
- added an abstraction layer for fields which can be used for search and
those fields can be edited in the solr ranking configruation
- the ranking value from solr within the field score is used to combine
remote search requests, which all are created using the same locally
defined boost values
- reduced the number of fields which are used for search (makes it
faster)
- replaced some text fields by string fields (makes indexing faster)
- removed classes which had no use
- made a large number of experiments for a better ranking and created a
temporary setting which prefers hits inside titles
- adjusted also the RWI-based ranking computation to 'prefer title'
- made special cases like for portal search where no post-processing and
post-ranking is wanted: this keeps the original ranking order as done by
Solr
- fixed many bugs with old settings for ranking
The default schema uses only some of them and the resting search index
has now the following properties:
- webgraph size will have about 40 times as much entries as default
index
- the complete index size will increase and may be about the double size
of current amount
As testing showed, not much indexing performance is lost. The default
index will be smaller (moved fields out of it); thus searching
can be faster.
The new index will cause that some old parts in YaCy can be removed,
i.e. specialized webgraph data and the noload crawler. The new index
will make it possible to:
- search within link texts of linked but not indexed documents (about 20
times of document index in size!!)
- get a very detailed link graph
- enhance ranking using a complete link graph
To get the full access to the new index, the API to solr has now two
access points: one with attribute core=collection1 for the default
search index and core=webgraph to the new webgraph search index. This is
also avaiable for p2p operation but client access is not yet
implemented.
- urlcitationindex != null check added to ResultEntry.referencesCount
- plus other places where conflicting procedure was used (and urlcitationindex not already checked != null)
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.
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
superfluous. The target is to make a solr document as the core of YaCy
documents which would cause that many conversions can be removed. On the
way to this target the Equivalence of URIMetadataRow and URIMetadataNode
had to be removed to expose the usage of the old URIMetadataRow data
structure.
This refactoring already removes unneccessary conversions and should
make memory usage during indexing lower.
which had been then mixed with remote RWIs. Now these Solr documents are
feeded into the result set as they appear during local and remote
search. That makes the search much faster.
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.
metadata representation from the solr index. This shall replace metadata
from the built-in database in the future.
- added the Solr-driven metadata into the search index of YaCy which
makes it now possible to run YaCy without the old metadata index. This
is a major stept forward to a full migration to Solr.
Michael Peter Christen