hold a date for each URL to record when a url was first seen. This is
then used to overwrite the modification date for urls upon recrawl in
case that the first-seen date is before the latest document date. This
behaviour is necessary due to the common behaviour of content management
systems which attach always the current date to all documents. Using the
firstSeen database it is possible to approximate a real first document
creation date in case that the crawler starts frequently for the same
domain. As a result the search results ordered by date have a much
better quality and the usage of YaCy as search agent for latest news has
a better quality.
postprocessing the solr documents are now not completely retrieved.
instead, only fiels, needed for the postprocessing are extracted. When
Solr document are written, this is done using partial updates.
This increases postprocessing speed by about 50% for embedded Solr
configurations. For external Solr configurations the enhancement should
be much higher because the postprocessing with remote Solr is very slow.
When doing partial updates to a remote Solr, this method should perform
much better than before, it is expected that this is even much higher
than the increase with local Solr.
(this eventually can benefit image search by using mime only)
reduce redundant field assignment for Solrdocuments created from URIMetadataNode (URIMetadataNode = SolrDocument with partially assigned fields)
it is now possible to get the results in two steps:
- first retrieve all IDs as given for a query
- then retieve each document individually
This was necessary for very large result sets where a query may run for
hours and is possibly terminated by a solr-internal timeout. This occurs
regulary during postprocessing and therefore this commit may fix
unwanted postprocessing terminations.
during document parsing; instead use the same references that would also
be written into the webgraph. That should cause that the webgraph and
the citation index express the exact same semantic.
see http://mantis.tokeek.de/view.php?id=437
test result (concurrency=7)
2000 docs = eom always
1000 docs = eom always
100 docs = eom never
chosen -> 200 docs (eom not encountered during test with 1GB mem setting)
formulated as edismax query but this was not set as query attribut. The
defType=edismax property needs a qf-field, so this was added as well. Do
not remove that field again! This fixes also a problem with title-unique
computation.
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.
- Web servers may now deliver YaCy-specific http header field with a
title and keywords. The new http header fields are:
X-YaCy-Media-Title - to be used for media (image, audio, video) titles
X-YaCy-Media-Keywords - to be used for media (image, audio, video)
keywords
- both fields are written to document fields title and keywords and are
searched also during image search.
- to make the usage of arbitrary http header fields (including this new
fields) possible in the /api/push_p.json servlet, a new POST argument is
also introduced to push http header fields. The new POST attribute is
named "responseHeader-X" (where X is the counter). It is allowed to use
this attribute as multi-attribute several times, each can be filled with
a http header line.
- see /api/push_p.html for examples
Michael Peter Christen