To support transitions from one search engine to a different one, or
to a different installation of the same kind, this feature allows for
queries to use a different search engine from indexing. So you can
reindex (and do all other search operation) on one server, while
user queries are unaffected on a different server.
This feature supports changing between search engine types, and also
between two Solr installations.
Adding documents in batches instead of one at a time can make
indexing using Solr significantly faster.
This adds new API functions for search engines, including
add_document_batch() to add a batch of documents,
supports_add_document_batch(), get_batch_max_documents() and
get_batch_max_content().
Adds new API support within search engines for optional methods to
delete data for courses and contexts, and implements this for the
two core search plugins (simpledb and solr).
The new API is automatically called when courses or contexts are
deleted. When a whole course is deleted, it only sends the course
delete rather than sending 1,000 separate context deletions as
each activity/block is deleted.
Implements a mechanism by which search engines can provide different
result orderings, and implements a 'by location' ordering within the
Solr search engine (available whenever the user starts their search
from within a course or activity).
Ensures that Solr will return available results, even if there are many
misses when using check_access(), by asking Solr for more results if the
counter says there should be more.
Improves performance by ending processing as soon as the requested page
of results is processed. Remaining number of pages is an "estimate"
based on the total result count from Solr and how many items we have
rejected up to this point.
Expand the Solr engine to use the built in (to Solr) Tika
file indexing engine. Files are shipped off for indexing with
curl. Each file must have it's own document. So grouping is
used to keep files and Moodle docs associated.
