With the appropriate vocabulary settings in Vocabulary_p.html page, this
can produce Vocabulary search facets displaying item types referenced in
html documents by microdata annotation.
Tested notably, but not limited to, vocabulary classes/types defined by
Schema.org and Dublin Core.
This adds the possibility for the HTML parser to gather typed items URLs
annotated in HTML tags with itemscope and itemtype attributes (see
microdata specification https://www.w3.org/TR/microdata/ ), notably
Types from the schema.org vocabulary, but also Types/Classes from any
other vocabulary, such as the common ones listed in the RDFa core
context ( https://www.w3.org/2011/rdfa-context/rdfa-1.1.html ).
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.
Required to properly run on systems with default locale set to Turkish
language, as with this locale the 'i' character has different upper and
lower case flavors than with other locales.
As reported edycop in mantis 765 (
http://mantis.tokeek.de/view.php?id=765 ), parsing of xlsx files was
quite incomplete.
Now properly support "Shared String Table" entry in Office Open XML
spreadsheets, an also detect embedded URLs.
Integrating the Apache poi-ooxml library could be an option for finer
OOXML formats support, but their SAX style parsing example (
http://poi.apache.org/spreadsheet/how-to.html#xssf_sax_api ) tends to
show that a custom SAX handler is still efficient for lightweight and
low memory footprint processing.
Some web servers provide both 'Content-Encoding : "gzip"' and
'Content-Type : "application/x-gzip"' HTTP headers on their ".gz" files.
This was annoying to fail on such resources which are not so uncommon,
while non conforming (see RFC 7231 section 3.1.2.2 for
"Content-Encoding" header specification
https://tools.ietf.org/html/rfc7231#section-3.1.2.2)
Thus enable getpageinfo_p API to return something in a reasonable amount
of time on resources over MegaBytes size range.
Support added first with the generic XML parser, for other formats
regular crawler limits apply as usual.
Recursive processing was removed in commit
67beef657f, but one remained for anchors
content(likely omitted from refactoring). It is no more necessary :
other links such as images embedded in anchors are currently correctly
detected by the parser.
More annoying : that remaining recursive processing could lead to almost
endless processing when encountering some (invalid) HTML structures
involving nested anchors, as detected and reported by lucipher on YaCy
forum ( http://forum.yacy-websuche.de/viewtopic.php?f=23&t=6005 ).
For faster processing (measured about 2 times faster on many real-world
examples) and more advanced detection (previous algorithm detected only
URLs separated from the rest of the text by a space character).
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'.
This parser adds support for any XML based format other than already
supported XML vocabularies such XHTML, RSS/Atom feeds... It will
eventually be used as a fallback if one of these specific parsers fail,
before falling back to the existing genericParser which extracts not
that much useful information except URL tokens.
Also add when possible a warning level log message on input stream
closing error instead of failing silently. This could help understanding
some IO exceptions such as "too many files open".
luccioman