New "Media Type detection" section in the advanced crawl start page
allow to choose between :
- not loading URLs with unknown or unsupported file extension without
checking the actual Media Type (relying Content-Type header for now).
This was the old default behavior, faster, but not really accurate.
- always cross check URL file extension against the actual Media Type.
This lets properly parse URLs ending with an apparently odd file
extension, but which have actually a supported Media Type such as
text/html.
Sample URLs with misleading file extensions added as documentation in
the crawl start page.
fixes issue #244
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.
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.
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.
- Above brought up that parser start url parameter, declared as AnchorURL uses only methodes of parent object DigestURL (changed parameter declaration accordingly).
Reads document level included title and description and skips the graphic content to save bandwidth.
svg metadata element is not interpreted
- remove rdfParser from init (current function identical with genericParser)
reason: experimental implementatin of RDFa parser not executed (limited to special urls) but may cause error on normal html parsing due to a inputstream.reset
to support the new time parser and search functions in YaCy a high
precision detection of date and time on the day is necessary. That
requires that the time zone of the document content and the time zone of
the user, doing a search, is detected. The time zone of the search
request is done automatically using the browsers time zone offset which
is delivered to the search request automatically and invisible to the
user. The time zone for the content of web pages cannot be detected
automatically and must be an attribute of crawl starts. The advanced
crawl start now provides an input field to set the time zone in minutes
as an offset number. All parsers must get a time zone offset passed, so
this required the change of the parser java api. A lot of other changes
had been made which corrects the wrong handling of dates in YaCy which
was to add a correction based on the time zone of the server. Now no
correction is added and all dates in YaCy are UTC/GMT time zone, a
normalized time zone for all peers.
given css class and extends a given vocabulary with a term consisting
with the text content of the html class tag. Additionally, the term is
included into the semantic facet of the document. This allows the
creation of faceted search to documents without the pre-creation of
vocabularies; instead, the vocabulary is created on-the-fly, possibly
for use in other crawls. If any of the term scraping for a specific
vocabulary is successful on a document, this vocabulary is excluded for
auto-annotation on the page.
To use this feature, do the following:
- create a vocabulary on /Vocabulary_p.html (if not existent)
- in /CrawlStartExpert.html you will now see the vocabularies as column
in a table. The second column provides text fields where you can name
the class of html entities where the literal of the corresponding
vocabulary shall be scraped out
- when doing a search, you will see the content of the scraped fields in
a navigation facet for the given vocabulary
This is a modified genericImageParser adding tif (and psd) support even if java ImageIO plugin for tif is not installed in JDK.
Adds just tif and psd to the available parsers.
Uses the same library to extract metadata, so could eventually be merged with genericImageParser.
All detected metadata are added to the parsed document (potentially some more as with genericImageParser)
the parser initialization. To make the apk parser usable, the handling
of application type links had to be modified. Now all documents which
have not a parser attached are placed to the noload-queue while all
other documents are parsed using the associated parser class. This may
have side-Effects on other parsers and the display of different file
classes (images, apps, videos).
generic parser but extracts links like the htmlParser. This should be
used for ASCII documents without known text format annotation like
source code files or json documents. Probably also good for xml files
without known schema.
This organizes all urls to be loaded in separate queues for each host.
Each host separates the crawl depth into it's own queue. The primary
rule for urls taken from any queue is, that the crawl depth is minimal.
This produces a crawl depth which is identical to the clickdepth.
Furthermorem the crawl is able to create a much better balancing over
all hosts which is fair to all hosts that are in the queue.
This process will create a very large number of files for wide crawls in
the QUEUES folder: for each host a directory, for each crawl depth a
file inside the directory. A crawl with maxdepth = 4 will be able to
create 10.000s of files. To be able to use that many file readers, it
was necessary to implement a new index data structure which opens the
file only if an access is wanted (OnDemandOpenFileIndex). The usage of
such on-demand file reader shall prevent that the number of file
pointers is over the system limit, which is usually about 10.000 open
files. Some parts of YaCy had to be adopted to handle the crawl depth
number correctly. The logging and the IndexCreateQueues servlet had to
be adopted to show the crawl queues differently, because the host name
is attached to the port on the host to differentiate between http,
https, and ftp services.
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
- use ordered list to use preferred parser for mime/extension first (relates to html, rdfa, argument parser)
- harmonize xhtml extension config for the 3 html base parsers
-- for some documents genericParser grabs document instead of specific available parser due to unordered pick of 1st to try parser
(like .ps .rdf files and other)
- remove redundant file extension registration
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
without the file extension. This part of the file path is removed from
the multi-field url_paths_sxt, which has now not the file name as last
part of the path list.
The same applies to the new fields source_file_name_s and
target_file_name_s in the webgraph schema.
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.
on the jaudiotagger library. The parser is disabled by default as it
needs to store temporary files for non file:// protocols, which might be
disliked. For your local MP3-collection it loads nicely Artist,
Title, Album etc. from the audio files meta data.
of the major CPU users during snippet verification. The class was not
efficient for two reasons:
- it used a too complex input stream; generated from sources and UTF8
byte-conversions. The BufferedReader applied a strong overhead.
- to feed data into the SentenceReader, multiple toString/getBytes had
been applied until a buffered Reader from an input stream was possible.
These superfluous conversions had been removed.
- the best source for the Sentence Reader is a String. Therefore the
production of Strings had been forced inside the Document class.
later
- added abstract add, delete, get methods in the triplestore
- added generation of triples after auto-annotation
- migrated all MultiProtocolURI objects to DigestURI in the parser since
the url hash is needed as subject value in the triples in the triple
store
luccioman