This is a major step because solr removed support for embedded solr
instances in 9.0 and we want to keep it because we want to ship
YaCy with an embedded solr. It was necessary to add parts of solr
code into YaCy to make this migration possible. Further on with
Solr 9.1 they removed even more parts which are required for embedded
operation, therefore we cannot migrate yet further without big
changes.
If you are running a YaCy instance with Solr 8.x, the migration should
be done automatically. If not you require to first migrate to a YaCy
version 1.93 with Solr 8.x to migrate to Solr 8 data.
The export file can now be many files, called chunks.
By default still only one chunk is exported.
This function is required in case that the exported files shall be
imported to an elasticsearch/opensearch index. The bulk import function
of elasticsearch/opensearch is limited to 100MB. To make it possible to
import YaCy files, those must be splitted into chunks. Right now we
cannot estimate the chunk size as bytes, only as number of documents.
The user must do experiments to find out the optimum chunk max size,
like 50000 docs per chunk. Try this as first attempt.
instead of loading the solr document, an index only for the last loading
time was created. This prevents that solr has to fetch from its index
while the index is created. Excessive re-loading of documents while
indexing has shown to produce deadlocks, so this should now be
prevented.
- replace new guava 30 with older 25 because that is the correct
dependency for solr 8.8.1. The newer one did actually not work!
- index will be crated in a DATA/INDEX/freeworld/SEGMENTS/solr_8_8_1
subfolder. The older solr_6_6 index is not touched but also not
migrated. The index starts with fresh (empty) content.
- Older indexes must be migrated by hand (export/import) so far until a
better solution is found.
- Large schema adoptions for lucene 8.8.1
SimpleDateFormat must not be used by concurrent threads without
synchronization for parsing or formating dates as it is not thread-safe
(internally holds a calendar instance that is not synchronized).
Prefer now DateTimeFormatter when possible as it is thread-safe without
concurrent access performance bottleneck (does not internally use
synchronization locks).
This makes possbile to set up much more advanced document crawl filters,
by filtering on one or more document indexed fields before inserting in
the index.
Otherwise once this operation is applied, the remote Solr(s) instances
are deconnected and the embedded Solr is connected even if disabled by
setting "core.service.fulltext".
Also use constants for related default setting values.
When a crawl is started, a new field to exclude content from scraping is
available. The field can be identified with the class name of div tags.
All text contained in such a div tag where the configured class name(s)
match are not indexed, while the remaining page is indexed.
Especially for Turkish speaking users using "tr" as their system default
locale : strings for technical stuff (URLs, tag names, constants...)
must not be lower cased with the default locale, as 'I' doesn't becomes
'i' like in other locales such as "en", but becomes 'ı'.
When Webgraph Solr core is enabled, crawling and removing from index an
URL whose hash starts with the '-' character (example URL :
https://cs.wikipedia.org/ whose hash is "-2-HuTEndn4x") produced a full
ParseException stack trace in YaCy logs. This was not blocking because
the Solr query parser is able to escape itself the query and run it
successfully, but filled uselessly YaCy logs.
When using a public HTTP URL in /IndexImportMediawiki_p.html, the remote
file now is directly streamed and processed, allowing import of several
GB dumps even with a low memory remote peer, and without need to
manually download the dump file first.
low number of found documents - by adding additional end condition to
remove processed query with number of found docs <= process-chunck-size.
Noticed on query h4_txt:[* TO *], found 21, process 21, call of commit happend
but on next cycle same query again 21 docs found (while h4_txt was removed
from schema and committed inputdocuments).
As reported by Palulukas in YaCy forum
(http://forum.yacy-websuche.de/viewtopic.php?f=18&t=5944&sid=dcef5b899ab4aa9b40e3a3d158c13aed#p33454)
the Index Export operation can fails, notably when the Solr index
contains one or more documents with empty (despite required)
"load_date_dt" field.
This fixes the export failure when the situation finally occurs, but
more should be done to harden verifications on minimum required fields.
As discussed in PR #93 with @JeremyRand and @reger24 this new advanced
settings page includes:
- a new setting to control remote Solr responses encoding
- some existing debug settings which could not be set through the admin
user interface
refactor to using long in URIMetadataNode too (and related call parameters)
As remote rwi score's are not used (since v1.83) skip reading float-score ,
but keep in toString() for communication with older versions.
Even after network switch, ErroCache was still holding a reference to
the previous Solr cores, thus becoming useless until next YaCy restart.
Initial error cache filling with recent errors from the index was also
missing after the swtich.
The embedded core holds a lock on the index and must be closed. Earlier commit
comment states that core should be closed with solr instance instead on close
of connector.
Adjusted the InstanceMirror.close() to take care of closing the embedded
instance to release the lock.
In 2 routines of fulltext this was already explicite implemented (disconnectLocalSolr).
Now this disconnect is part of the InstanceMirror.close().
Michael Peter Christen