Sendu Bala
and 1 contributors

NAME

Bio::DB::NCBIHelper - A collection of routines useful for queries to NCBI databases.

SYNOPSIS

 # Do not use this module directly.

 # get a Bio::DB::NCBIHelper object somehow
 my $seqio = $db->get_Stream_by_acc(['MUSIGHBA1']);
 foreach my $seq ( $seqio->next_seq ) {
     # process seq
 }

DESCRIPTION

Provides a single place to setup some common methods for querying NCBI web databases. This module just centralizes the methods for constructing a URL for querying NCBI GenBank and NCBI GenPept and the common HTML stripping done in postprocess_data().

The base NCBI query URL used is: http://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi

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 one of the Bioperl mailing lists. Your participation is much appreciated.

  bioperl-l@bioperl.org                  - General discussion
  http://bioperl.org/wiki/Mailing_lists  - About the mailing lists

Reporting Bugs

Report bugs to the Bioperl bug tracking system to help us keep track the bugs and their resolution. Bug reports can be submitted via the web.

  http://bugzilla.open-bio.org/

AUTHOR - Jason Stajich

Email jason@bioperl.org

APPENDIX

The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _

get_params

 Title   : get_params
 Usage   : my %params = $self->get_params($mode)
 Function: Returns key,value pairs to be passed to NCBI database
           for either 'batch' or 'single' sequence retrieval method
 Returns : a key,value pair hash
 Args    : 'single' or 'batch' mode for retrieval

default_format

 Title   : default_format
 Usage   : my $format = $self->default_format
 Function: Returns default sequence format for this module
 Returns : string
 Args    : none

get_request

 Title   : get_request
 Usage   : my $url = $self->get_request
 Function: HTTP::Request
 Returns : 
 Args    : %qualifiers = a hash of qualifiers (ids, format, etc)

get_Stream_by_batch

  Title   : get_Stream_by_batch
  Usage   : $seq = $db->get_Stream_by_batch($ref);
  Function: Retrieves Seq objects from Entrez 'en masse', rather than one
            at a time.  For large numbers of sequences, this is far superior
            than get_Stream_by_[id/acc]().
  Example :
  Returns : a Bio::SeqIO stream object
  Args    : $ref : either an array reference, a filename, or a filehandle
            from which to get the list of unique ids/accession numbers.

NOTE: deprecated API. Use get_Stream_by_id() instead.

get_Stream_by_query

  Title   : get_Stream_by_query
  Usage   : $seq = $db->get_Stream_by_query($query);
  Function: Retrieves Seq objects from Entrez 'en masse', rather than one
            at a time.  For large numbers of sequences, this is far superior
            than get_Stream_by_[id/acc]().
  Example :
  Returns : a Bio::SeqIO stream object
  Args    : $query :   An Entrez query string or a
            Bio::DB::Query::GenBank object.  It is suggested that you
            create a Bio::DB::Query::GenBank object and get the entry
            count before you fetch a potentially large stream.

postprocess_data

 Title   : postprocess_data
 Usage   : $self->postprocess_data ( 'type' => 'string',
                                                         'location' => \$datastr);
 Function: process downloaded data before loading into a Bio::SeqIO
 Returns : void
 Args    : hash with two keys - 'type' can be 'string' or 'file'
                              - 'location' either file location or string 
                                           reference containing data

request_format

 Title   : request_format
 Usage   : my ($req_format, $ioformat) = $self->request_format;
           $self->request_format("genbank");
           $self->request_format("fasta");
 Function: Get/Set sequence format retrieval. The get-form will normally not
           be used outside of this and derived modules.
 Returns : Array of two strings, the first representing the format for
           retrieval, and the second specifying the corresponding SeqIO format.
 Args    : $format = sequence format

Bio::DB::WebDBSeqI methods

Overriding WebDBSeqI method to help newbies to retrieve sequences

get_Stream_by_acc

  Title   : get_Stream_by_acc
  Usage   : $seq = $db->get_Stream_by_acc([$acc1, $acc2]);
  Function: Gets a series of Seq objects by accession numbers
  Returns : a Bio::SeqIO stream object
  Args    : $ref : a reference to an array of accession numbers for
                   the desired sequence entries
  Note    : For GenBank, this just calls the same code for get_Stream_by_id()

_check_id

  Title   : _check_id
  Usage   : 
  Function: 
  Returns : A Bio::DB::RefSeq reference or throws
  Args    : $id(s), $string

delay_policy

  Title   : delay_policy
  Usage   : $secs = $self->delay_policy
  Function: return number of seconds to delay between calls to remote db
  Returns : number of seconds to delay
  Args    : none

  NOTE: NCBI requests a delay of 3 seconds between requests.  This method
        implements that policy.
 Title   : cookie
 Usage   : ($cookie,$querynum) = $db->cookie
 Function: return the NCBI query cookie
 Returns : list of (cookie,querynum)
 Args    : none

NOTE: this information is used by Bio::DB::GenBank in conjunction with efetch.

_parse_response

 Title   : _parse_response
 Usage   : $db->_parse_response($content)
 Function: parse out response for cookie
 Returns : empty
 Args    : none
 Throws  : 'unparseable output exception'