Algorithm-Dependency-Source-DBI
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Algorithm::Dependency
SYNOPSIS
use DBI;
use Algorithm::Dependency;
use Algorithm::Dependency::Source::DBI;
# Load the data from a database
my $data_source = Algorithm::Dependency::Source::DBI->new(
dbh => DBI->connect('dbi:SQLite:sqlite.db'),
select_ids => 'select name from stuff',
select_depends => 'select from, to from m2m_deps',
);
# Create the dependency object, and indicate the items that are already
# selected/installed/etc in the database
my $dep = Algorithm::Dependency->new(
source => $data_source,
selected => [ 'This', 'That' ]
) or die 'Failed to set up dependency algorithm';
# For the item 'Foo', find out the other things we also have to select.
# This WON'T include the item we selected, 'Foo'.
my $also = $dep->depends( 'Foo' );
print $also
? "By selecting 'Foo', you are also selecting the following items: "
. join( ', ', @$also )
: "Nothing else to select for 'Foo'";
# Find out the order we need to act on the items in.
# This WILL include the item we selected, 'Foo'.
my $schedule = $dep->schedule( 'Foo' );
DESCRIPTION
The Algorithm::Dependency module has shown itself to be quite reliable
over a long period of time, as well as relatively easy to setup and use.
However, recently there has been an increasing use of things like
DBD::SQLite to store and distribute structured data.
Algorithm::Dependency::Source::DBI extends Algorithm::Dependency by
providing a simple way to create dependency objects that pull their data
from a database directly.
METHODS
new
my $simple = Algorithm::Dependency::Source::DBI->new(
dbh => $dbi_db_handle,
select_ids => 'select name from stuff',
select_depends => 'select from, to from m2m_deps',
);
my $complex = Algorithm::Dependency::Source::DBI->new(
dbh => $dbi_db_handle,
select_ids => [ 'select name from stuff where foo = ?', 'bar' ],
select_depends => [ 'select from, to from m2m_deps where from = ?', 'bar' ],
);
The "new" constructor takes three named named params.
The "dbh" param should be a standard DBI database connection.
The "select_ids" param is either a complete SQL string, or a reference
to an "ARRAY" containing a SQL string with placeholders and matching
variables.
When executed on the database, it should return a single column
containing the complete set of all item identifiers.
The "select_depends" param is either a complete SQL string, or a
reference to an "ARRAY" containing a SQL string with placeholders and
matching variables.
When executed on the database, it should return two columns containing
the complete set of all dependencies, where identifiers in the
first-column depends on identifiers in the second-column.
Returns a new Algorithm::Dependency::Source::DBI object, or dies on
error.
dbh
The "dbh" accessor returns the database handle provided to the
constructor.
select_ids
The "select_ids" accessor returns the SQL statement provided to the
constructor. If a raw string was provided, it will be returned as a
reference to an "ARRAY" containing the SQL string and no params.
select_depends
The "select_depends" accessor returns the SQL statement provided to the
constructor. If a raw string was provided, it will be returned as a
reference to an "ARRAY" containing the SQL string and no params.
SUPPORT
To file a bug against this module, use the CPAN bug tracking system
<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Algorithm-Dependency-Sou
rce-DBI>
For other comments, contact the author.
lib/Algorithm/Dependency/Source/DBI.pm view on Meta::CPAN
=head1 SYNOPSIS
use DBI;
use Algorithm::Dependency;
use Algorithm::Dependency::Source::DBI;
# Load the data from a database
my $data_source = Algorithm::Dependency::Source::DBI->new(
dbh => DBI->connect('dbi:SQLite:sqlite.db'),
select_ids => 'select name from stuff',
select_depends => 'select from, to from m2m_deps',
);
# Create the dependency object, and indicate the items that are already
# selected/installed/etc in the database
my $dep = Algorithm::Dependency->new(
source => $data_source,
selected => [ 'This', 'That' ]
) or die 'Failed to set up dependency algorithm';
# For the item 'Foo', find out the other things we also have to select.
# This WON'T include the item we selected, 'Foo'.
my $also = $dep->depends( 'Foo' );
print $also
? "By selecting 'Foo', you are also selecting the following items: "
. join( ', ', @$also )
: "Nothing else to select for 'Foo'";
# Find out the order we need to act on the items in.
# This WILL include the item we selected, 'Foo'.
my $schedule = $dep->schedule( 'Foo' );
=head1 DESCRIPTION
The L<Algorithm::Dependency> module has shown itself to be quite reliable
over a long period of time, as well as relatively easy to setup and use.
However, recently there has been an increasing use of things like
L<DBD::SQLite> to store and distribute structured data.
lib/Algorithm/Dependency/Source/DBI.pm view on Meta::CPAN
#####################################################################
# Constructor and Accessors
=pod
=head2 new
my $simple = Algorithm::Dependency::Source::DBI->new(
dbh => $dbi_db_handle,
select_ids => 'select name from stuff',
select_depends => 'select from, to from m2m_deps',
);
my $complex = Algorithm::Dependency::Source::DBI->new(
dbh => $dbi_db_handle,
select_ids => [ 'select name from stuff where foo = ?', 'bar' ],
select_depends => [ 'select from, to from m2m_deps where from = ?', 'bar' ],
);
The C<new> constructor takes three named named params.
The C<dbh> param should be a standard L<DBI> database connection.
The C<select_ids> param is either a complete SQL string, or a reference to
an C<ARRAY> containing a SQL string with placeholders and matching
variables.
When executed on the database, it should return a single column containing
the complete set of all item identifiers.
The C<select_depends> param is either a complete SQL string, or a reference
to an C<ARRAY> containing a SQL string with placeholders and matching
variables.
When executed on the database, it should return two columns containing
the complete set of all dependencies, where identifiers in the first-column
depends on identifiers in the second-column.
Returns a new L<Algorithm::Dependency::Source::DBI> object, or dies on
error.
=cut
sub new {
my $class = shift;
# Create the object
my $self = bless { @_ }, $class;
# Apply defaults
if ( _STRING($self->{select_ids}) ) {
$self->{select_ids} = [ $self->{select_ids} ];
}
if ( _STRING($self->{select_depends}) ) {
$self->{select_depends} = [ $self->{select_depends} ];
}
# Check params
unless ( _INSTANCE($self->dbh, 'DBI::db') ) {
Carp::croak("The dbh param is not a DBI database handle");
}
unless ( _ARRAY($self->select_ids) and _STRING($self->select_ids->[0]) ) {
Carp::croak("Missing or invalid select_ids param");
}
unless ( _ARRAY($self->select_depends) and _STRING($self->select_depends->[0]) ) {
Carp::croak("Did not provide the select_depends query");
}
return $self;
}
=pod
=head2 dbh
The C<dbh> accessor returns the database handle provided to the constructor.
=cut
sub dbh {
$_[0]->{dbh};
}
=pod
=head2 select_ids
The C<select_ids> accessor returns the SQL statement provided to the
constructor. If a raw string was provided, it will be returned as a
reference to an C<ARRAY> containing the SQL string and no params.
=cut
sub select_ids {
$_[0]->{select_ids};
}
=pod
=head2 select_depends
The C<select_depends> accessor returns the SQL statement provided to
the constructor. If a raw string was provided, it will be returned as
a reference to an C<ARRAY> containing the SQL string and no params.
=cut
sub select_depends {
$_[0]->{select_depends};
}
#####################################################################
# Main Functionality
sub _load_item_list {
my $self = shift;
# Get the list of ids
my $ids = $self->dbh->selectcol_arrayref(
$self->select_ids->[0],
{}, # No options
@{$self->select_ids}[1..-1],
);
my %hash = map { $_ => [ ] } @$ids;
# Get the list of links
my $depends = $self->dbh->selectall_arrayref(
$self->select_depends->[0],
{}, # No options
@{$self->select_depends}[1..-1],
);
foreach my $depend ( @$depends ) {
next unless $hash{$depend->[0]};
next unless $hash{$depend->[1]};
push @{$hash{$depend->[0]}}, $depend->[1];
}
# Now convert to items
my @items = map {
Algorithm::Dependency::Item->new( $_, @{$hash{$_}} )
t/02_selftest.t view on Meta::CPAN
SCOPE: {
my $db = empty_db();
isa_ok( $db, 'DBI::db' );
}
SCOPE: {
my $db = create_db( $sql_file, $csv_file );
isa_ok( $db, 'DBI::db' );
my $data = $db->selectall_arrayref( 'select * from one order by foo' );
is_deeply( $data, [
[ 1, 'Hello, World!' ],
[ 2, 'secondrow' ],
], 'Data in table one matches expected' );
my $rv = $db->selectrow_arrayref( 'select count(*) from two' );
is_deeply( $rv, [ 0 ], 'Nothing in table two' );
}
t/03_simple.t view on Meta::CPAN
#####################################################################
# Main Tests
my $dbh = create_db(@create);
isa_ok( $dbh, 'DBI::db' );
my $select_ids = "select id from one order by id";
my $select_depends = "select foo, bar from links";
# Create the source
my $source = Algorithm::Dependency::Source::DBI->new(
dbh => $dbh,
select_ids => $select_ids,
select_depends => $select_depends,
);
isa_ok( $source, 'Algorithm::Dependency::Source' );
isa_ok( $source, 'Algorithm::Dependency::Source::DBI' );
isa_ok( $source->dbh, 'DBI::db' );
is_deeply( $source->select_ids, [ $select_ids ], '->select_ids ok' );
is_deeply( $source->select_depends, [ $select_depends ], '->select_depends ok' );
ok( $source->load, '->load ok' );
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