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
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
queue and not from virtual documents generated by the parser.
- The parser now generates nice description texts for NOLOAD entries
which shall make it possible to find media content using the search
index and not using the media prefetch algorithm during search (which
was costly)
- Removed the media-search prefetch process from image search
some file types are containers for several files. These containers had been parsed in such a way that the set of resulting parsed content was merged into one single document before parsing. Using this parser infrastructure it is not possible to parse document containers that contain individual files. An example is a rss file where the rss messages can be treated as individual documents with their own url reference. Another example is a surrogate file which was treated with a special operation outside of the parser infrastructure.
This commit introduces a redesigned parser interface and a new abstract parser implementation. The new parser interface has now only one entry point and returns always a set of parsed documents. In case of single documents the parser method returns a set of one documents.
To be compliant with the new interface, the zip and tar parser had been also completely redesigned. All parsers are now much more simple and cleaner in its structure. The switchboard operations had been extended to operate with sets of parsed files, not single parsed files.
additionally, parsing of jar manifest files had been added.
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@6955 6c8d7289-2bf4-0310-a012-ef5d649a1542
- it is now possible to crawl the local file system with an intranet peer
- redesign of URL handling
- refactoring: created LGPLed package cora: 'content retrieval api' which may be used externally by other applications without yacy core elements because it has no dependencies to other parts of yacy
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@6902 6c8d7289-2bf4-0310-a012-ef5d649a1542
