Provided by: libbio-biblio-perl_1.70-2_all 
NAME
Bio::DB::BiblioI - an interface to a Bibliographic Query Service
VERSION
version 1.70
SYNOPSIS
This is an interface module - you do not instantiate it. Use Bio::Biblio module:
use Bio::Biblio;
my $biblio = Bio::Biblio->new(@args);
DESCRIPTION
This interface describes the methods for accessing a bibliographic repository, for
querying it and for retrieving citations from it. The retrieved citations are in XML
format and can be converted to perl objects using Bio::Biblio::IO.
The interface complies (with some simplifications) with the specification described in the
OpenBQS project. Its home page is at http://www.ebi.ac.uk/~senger/openbqs/.
ATTRIBUTES
has_next
Usage : my $is = $biblio->has_next;
Returns : 1 or undef
Args : none
It returns 1 if there is a next citation available in the underlying query collection.
Otherwise it returns undef.
It throws an exception if this object does not represent any query result - see
explanation in method reset_retrieval elsewhere in this document.
exists
Usage : my $exists = $biblio->exists;
Returns : 1 or undef
Args : none
It returns 1 if the underlying query collection represented by the $biblio object still
exists (on the server side).
If you have a collection ID (e.g. stored or printed in a previous session) but you do not
have anymore a "Bio::Biblio" object representing it this is how you can check the
collection existence:
use Bio::Biblio;
print
Bio::Biblio->new(-collection_id => '1014324148861')->exists;
It throws an exception if this object does not represent any query result - see
explanation in method reset_retrieval elsewhere in this document.
contains
Usage : my $yes = $biblio->contains ($vocabulary_name, $value);
Returns : 1 or undef
Args : $vocabulary_name defines a vocabulary where to look,
and a $value defines what to look for
It returns 1 if the given controlled vocabulary contains the given value.
For example, when you know, that a vocabulary "MEDLINE/JournalArticle/properties" contains
value "COUNTRY" you can use it in the find method:
$biblio->find ('United States', 'COUNTRY');
METHODS
get_collection_id
Usage : my $collection_id = $biblio->get_collection_id;
Returns : string identifying a query collection
represented by the $biblio object
Args : none
Every query collection is uniquely identify-able by its collection ID. The returned value
can be used to populate another $biblio object and then to access that collection.
get_count
Usage : my $count = $biblio->get_count;
Returns : integer
Args : none, or a string identifying a query collection
It returns a number of citations in the query collection represented by the calling
$biblio object, or in the collection whose ID is given as an argument.
find
Usage : my $new_biblio = $biblio->find ($keywords, $attrs);
my $new_biblio = $biblio->find ('perl', 'abstract');
my $new_biblio = $biblio->find ( [ 'perl', 'Java' ] );
Returns : new Bio::Biblio object representing a new query
collection
Args : $keywords - what to look for (mandatory)
- a comma-delimited list of keywords, or
- an array reference with keywords as elements
$attrs - where to look in (optional)
- a comma-delimited list of attribute names, or
- an array reference with attribute names as elements
This is the main query method. It looks for the $keywords in a default set of attributes,
or - if $attrs given - only in the given attributes.
Because it returns a new Bio::Biblio object which can be again queried it is possible to
chain together several invocations:
$biblio->find ('Brazma')->find ('Robinson')->get_collection_id;
reset_retrieval
Usage : $biblio->reset_retrieval;
Returns : nothing
Args : none
It sets an iterator stored in the $biblio object back to its beginning. After this, the
retrieval methods has_next, get_next and get_more start to iterate the underlying query
collection again from its start.
It throws an exception if this object does not represent any query result (e.i. it does
not contain a collection ID). Note that a collection ID is created automatically when this
object was returned by a find method, or it can be assigned in a constructor using
argument -collection_id.
get_next
Usage : my $citation = $biblio->get_next;
Returns : a citation in an XML format
Args : none
It returns the next available citation from the underlying query collection. It throws an
exception if there are no more citations. In order to avoid this, use it together with the
has_next method:
my $result = $biblio->find ('brazma', 'authors');
while ( $result->has_next ) {
print $result->get_next;
}
It also throws an exception if this object does not represent any query result - see
explanation in the reset_retrieval elsewhere in this document.
get_more
Usage : my $r_citations = $biblio->get_more (5);
Returns : an array reference - each element has a citation
in an XML format
Args : an integer 'how_many' citations to return;
default is 1 - but it is assigned with warning
It returns the next how_many available citations from the underlying query collection. It
does not throw any exception if 'how_many' is more than currently available - it simply
returns less. However, it throws an exception if used again without calling first
reset_retrieval.
It also throws an exception if this object does not represent any query result - see
explanation in method reset_retrieval elsewhere in this document.
get_all_ids
Usage : my $r_ids = $biblio->get_all_ids;
Returns : an array reference - each element has
a citation identifier
Args : none
The identifiers of all citations in the underlying query collection are returned. A usual
pattern is to use them then in the get_by_id method:
my $biblio = $repository->find ('brazma')->find ('robinson');
foreach my $id ( @{ $biblio->get_all_ids } ) {
print $biblio->get_by_id ($id);
}
It throws an exception if this object does not represent any query result - see
explanation in method reset_retrieval elsewhere in this document.
get_by_id
Usage : my $citation = $biblio->get_by_id ('12368254');
Returns : a citation in an XML format
Args : a citation identifier (PMID for Medline)
It returns a citation - disregarding if the citation is or is not in the underlying query
collection (of course, it must be in the repository).
get_all
Usage : my $all = $biblio->get_all;
Returns : a (big) string with all citations in an XML format
Args : none
It returns an XML valid string (which means that individual citations are also surrounded
by a "set" XML tag) representing all citations from the underlying query collection.
Note that some servers may limit the number of citations which can be returned by this
method. In such case you need either to refine further your query collection (using find
method) or to retrieve results by iteration (methods has_next, get_next, get_more).
It throws an exception if this object does not represent any query result - see
explanation in method reset_retrieval elsewhere in this document.
destroy
Usage : $biblio->destroy;
Returns : nothing
Args : none
It sends a message to the remote server to forget (or free, or destroy - whatever server
choose to do) the query collection represented by this object.
It throws an exception if this object does not represent any query collection.
get_vocabulary_names
Usage : print join ("\n", @{ $biblio->get_vocabulary_names });
Returns : an array reference - each element has a name
of a controlled vocabulary
Args : none
The controlled vocabularies allow to introspect bibliographic repositories and to find
what citation resource types (such as journal and book articles, patents or technical
reports) are provided by the repository, what attributes they have, eventually what
attribute values are allowed.
This method returns names of all available controlled vocabularies. The names can than be
used in other methods dealing with vocabularies: contains, get_entry_description,
get_all_values, and get_all_entries.
get_entry_description
Usage : $biblio->get_entry_description ($voc_name, $value);
Returns : a string with a desciption
Args : $voc_name defines a vocabulary where to look,
and a $value defines whose description to return
Each vocabulary entry has its value (mandatory attribute), and can have a description
(optional attribute). The description may be just a human readable explanation of an
attribute, or it can have more exact meaning. For example, the server implementation of
the bibliographic query service provided by the EBI puts into attribute descriptions words
queryable and/or retrievable to distinguish the role of the attributes.
It throws an exception if either vocabulary or value do not exist.
get_all_values
Usage : $biblio->get_all_values ($vocabulary_name);
Returns : an array reference - each element has a value (scalar)
from the given controlled vocabulary
Args : $vocabulary_name defines a vocabulary whose values
are being returned
It returns all values of the given vocabulary. It throws an exception if the vocabulary
does not exist.
get_all_entries
Usage : $biblio->get_all_entries ($vocabulary_name);
Returns : a hash reference - keys are vocabulary values
and values are their descriptions
Args : $vocabulary_name defines a vocabulary whose entries
are being returned
It returns pairs of values and their descriptions of the whole vocabulary. It throws an
exception if the vocabulary does not exist.
This is one way how to get it and print it:
my $name = 'MEDLINE2005/JournalArticle/properties';
use Data::Dumper;
print Data::Dumper->Dump ( [$biblio->get_all_entries ($name)],
['All entries']);
FEEDBACK
Mailing lists
User feedback is an integral part of the evolution of this and other Bioperl modules. Send
your comments and suggestions preferably to the Bioperl mailing list. Your participation
is much appreciated.
bioperl-l@bioperl.org - General discussion
http://bioperl.org/wiki/Mailing_lists - About the mailing lists
Support
Please direct usage questions or support issues to the mailing list: bioperl-l@bioperl.org
rather than to the module maintainer directly. Many experienced and reponsive experts will
be able look at the problem and quickly address it. Please include a thorough description
of the problem with code and data examples if at all possible.
Reporting bugs
Report bugs to the Bioperl bug tracking system to help us keep track of the bugs and their
resolution. Bug reports can be submitted via the web:
https://redmine.open-bio.org/projects/bioperl/
LEGAL
Authors
Martin Senger <martin.senger@gmail.com>
Copyright and License
This software is Copyright (c) by 2002 European Bioinformatics Institute and released
under the license of the same terms as the perl 5 programming language system itself