Raw content of Bio::DB::GFF::Adaptor::biofetch
<![CDATA[package Bio::DB::GFF::Adaptor::biofetch;
=head1 NAME
Bio::DB::GFF::Adaptor::biofetch -- Cache BioFetch objects in a Bio::DB::GFF database
=head1 SYNOPSIS
Proof of principle. Not for production use.
=head1 DESCRIPTION
This adaptor is a proof-of-principle. It is used to fetch BioFetch
sequences into a Bio::DB::GFF database (currently uses a hard-coded
EMBL database) as needed. This allows the Generic Genome Browser to
be used as a Genbank/EMBL browser.
=head1 AUTHOR
Lincoln Stein E<lt>lstein@cshl.orgE<gt>.
Copyright 2002 Cold Spring Harbor Laboratory.
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=cut
use strict;
use Bio::DB::GFF::Util::Rearrange; # for rearrange()
use Bio::DB::GFF::Adaptor::dbi::mysql;
use Bio::DB::BioFetch;
use Bio::SeqIO;
use vars qw(@ISA %preferred_tags);
@ISA = qw(Bio::DB::GFF::Adaptor::dbi::mysql);
# priority for choosing names of CDS tags, higher is higher priority
%preferred_tags = (
strain => 10,
organism => 20,
protein_id => 40,
locus_tag => 50,
locus => 60,
gene => 70,
standard_name => 80,
);
=head2 new
Title : new
Usage : $db = Bio::DB::GFF->new(-adaptor=>'biofetch',@args)
Function: create a new adaptor
Returns : a Bio::DB::GFF object
Args : see below
Status : Public
This is the constructor for the adaptor. It is called automatically
by Bio::DB::GFF-E<gt>new. In addition to arguments that are common among
all adaptors, the following class-specific arguments are recgonized:
Argument Description
-------- -----------
-dsn the DBI data source, e.g. 'dbi:mysql:ens0040'
-user username for authentication
-pass the password for authentication
-proxy [['http','ftp'],'http://proxy:8080']
-dsn,-user and -pass indicate the local database to cache results in,
and as are per Bio::DB::GFF::Adaptor::dbi. The -proxy argument allows
you to set the biofetch web proxy, and uses the same syntax described
for the proxy() method of L<Bio::DB::WebDBSeqI>, except that the
argument must be passed as an array reference.
=cut
sub new {
my $class = shift;
my $self = $class->SUPER::new(@_);
my ($proxy) = rearrange(['PROXY'],@_);
if ($proxy) {
my @args = ref($proxy) ? @$proxy : eval $proxy;
$self->{_proxy} = \@args if @args;
}
$self;
}
sub segment {
my $self = shift;
my @segments = $self->SUPER::segment(@_);
if (!@segments) {
my $refclass = $self->refclass;
my %args = $self->setup_segment_args(@_);
if ($args{-class} && $args{-class} =~ /$refclass/oi) {
return unless $self->load_from_embl('embl'=>$args{-name});
@segments = $self->SUPER::segment(@_);
} elsif ($args{-class} && $args{-class} =~ /refseq|swall|embl/i) { #hack to get refseq names
return unless $self->load_from_embl(lc($args{-class})=>$args{-name});
$args{-class} = $self->refclass;
@segments = $self->SUPER::segment(%args);
}
}
$self->_multiple_return_args(@segments);
}
# default is to return 'Sequence' as the class of all references
sub refclass {
my $self = shift;
my $refname = shift;
'Accession';
}
sub load_from_embl {
my $self = shift;
my $db = shift;
my $acc = shift or $self->throw('Must provide an accession ID');
my $biofetch;
if ($self->{_biofetch}{$db}) {
$biofetch = $self->{_biofetch}{$db};
} else {
$biofetch = $self->{_biofetch}{$db} = Bio::DB::BioFetch->new(-db=>$db);
$biofetch->retrieval_type('tempfile');
$biofetch->proxy(@{$self->{_proxy}}) if $self->{_proxy};
}
my $seq = eval {$biofetch->get_Seq_by_id($acc)} or return;
$self->_load_embl($acc,$seq);
1;
}
sub load_from_file {
my $self = shift;
my $file = shift;
my $format = $file =~ /\.(gb|genbank|gbk)$/i ? 'genbank' : 'embl';
my $seqio = Bio::SeqIO->new( '-format' => $format, -file => $file);
my $seq = $seqio->next_seq;
$self->_load_embl($seq->accession,$seq);
1;
}
sub _load_embl {
my $self = shift;
my $acc = shift;
my $seq = shift;
my $refclass = $self->refclass;
my $locus = $seq->id;
# begin loading
$self->setup_load();
# first synthesize the entry for the top-level feature
my @aliases;
foreach ($seq->accession,$seq->get_secondary_accessions) {
next if lc($_) eq lc($acc);
push @aliases,[Alias => $_];
}
$self->load_gff_line(
{
ref => $acc,
class => $refclass,
source => 'EMBL',
method => 'origin',
start => 1,
stop => $seq->length,
score => undef,
strand => '.',
phase => '.',
gclass => $self->refclass,
gname => $acc,
tstart => undef,
tstop => undef,
attributes => [[Note => $seq->desc],@aliases],
}
);
# now load each feature in turn
for my $feat ($seq->all_SeqFeatures) {
my $attributes = $self->get_attributes($feat);
my $name = $self->guess_name($attributes);
my $location = $feat->location;
my @segments = map {[$_->start,$_->end,$_->seq_id]}
$location->can('sub_Location') ? $location->sub_Location : $location;
my $type = $feat->primary_tag eq 'CDS' ? 'mRNA' : $feat->primary_tag;
my $parttype = $feat->primary_tag eq 'gene' ? 'exon' : $feat->primary_tag;
if ($feat->primary_tag =~ /^(gene|CDS)$/) {
$self->load_gff_line( {
ref => $acc,
class => $refclass,
source => 'EMBL',
method => $type,
start => $location->start,
stop => $location->end,
score => $feat->score || undef,
strand => $feat->strand > 0 ? '+' : ($feat->strand < 0 ? '-' : '.'),
phase => $feat->frame || '.',
gclass => $name->[0],
gname => $name->[1],
tstart => undef,
tstop => undef,
attributes => $attributes,
}
);
@$attributes = ();
}
for my $segment (@segments) {
$self->load_gff_line( {
ref => $segment->[2] eq $locus ? $acc : $segment->[2],
class => $refclass,
source => 'EMBL',
method => $parttype,
start => $segment->[0],
stop => $segment->[1],
score => $feat->score || undef,
strand => $feat->strand > 0 ? '+' : ($feat->strand < 0 ? '-' : '.'),
phase => $feat->frame || '.',
gclass => $name->[0],
gname => $name->[1],
tstart => undef,
tstop => undef,
attributes => $attributes,
}
);
}
}
# finish loading
$self->finish_load();
# now load the DNA
$self->load_sequence_string($acc,$seq->seq);
1;
}
sub get_attributes {
my $self = shift;
my $seq = shift;
my @tags = $seq->all_tags or return;
my @result;
foreach my $tag (@tags) {
foreach my $value ($seq->each_tag_value($tag)) {
push @result,[$tag=>$value];
}
}
\@result;
}
sub guess_name {
my $self = shift;
my $attributes = shift;
my @ordered_attributes = sort {($preferred_tags{$a->[0]} || 0) <=> ($preferred_tags{$b->[0]} || 0)} @$attributes;
my $best = pop @ordered_attributes;
@$attributes = @ordered_attributes;
return $best;
}
1;
]]>