File Coverage

blib/lib/HashDataRole/Source/DBI.pm

Criterion	Covered	Total	%
statement	78	90	86.6
branch	30	46	65.2
condition	7	21	33.3
subroutine	12	14	85.7
pod	1	11	9.0
total	128	182	70.3

package HashDataRole::Source::DBI;

our $AUTHORITY = 'cpan:PERLANCAR'; # AUTHORITY
our $DATE = '2021-05-21'; # DATE
our $DIST = 'HashDataRoles-Standard'; # DIST
our $VERSION = '0.001'; # VERSION

use 5.010001;
use Role::Tiny;
use Role::Tiny::With;
with 'HashDataRole::Spec::Basic';

sub new {
    my ($class, %args) = @_;

    my $dsn      = delete $args{dsn};
    my $user     = delete $args{user};
    my $password = delete $args{password};
    my $dbh = delete $args{dbh};
    if (defined $dbh) {
    } elsif (defined $dsn) {
        require DBI;
        $dbh = DBI->connect($dsn, $user, $password, {RaiseError=>1});
    }

    my $table      = delete $args{table};  # XXX quote
    my $key_column = delete $args{key_column}; # XXX quote
    my $val_column = delete $args{val_column}; # XXX quote

    my $iterate_sth    = delete $args{iterate_sth};
    unless (defined $iterate_sth) {
        die "You don't specify 'iterate_sth', so you must specify ".
            "dbh/dsn+user+password & table & key_column & val_column, ".
            "so I can create a statement handle"
            unless $dbh && defined($table) && defined($key_column) && defined($val_column);
        my $query = "SELECT $key_column,$val_column FROM $table";
        $iterate_sth = $dbh->prepare($query);
    }

    my $get_by_key_sth = delete $args{get_by_key_sth};
    unless (defined $get_by_key_sth) {
        die "You don't specify 'iterate_sth', so you must specify ".
            "dbh/dsn+user+password & table & key_column & val_column, ".
            "so I can create a statement handle"
            unless $dbh && defined($table) && defined($key_column) && defined($val_column);
        my $query = "SELECT $val_column FROM $table WHERE $key_column=?";
        $get_by_key_sth = $dbh->prepare($query);
    }

    my $row_count_sth = delete $args{row_count_sth};
    unless (defined $row_count_sth) {
        die "You don't specify 'iterate_sth', so you must specify ".
            "dbh/dsn+user+password & table, ".
            "so I can create a statement handle"
            unless $dbh && defined($table);
        my $query = "SELECT COUNT(*) FROM $table";
        $row_count_sth = $dbh->prepare($query);
    }

    die "Unknown argument(s): ". join(", ", sort keys %args)
        if keys %args;

    bless {
        #dbh => $dbh,
        iterate_sth => $iterate_sth,
        get_by_key_sth => $get_by_key_sth,
        row_count_sth => $row_count_sth,
        pos => undef, # iterator pos
        #buf => '', # exists when there is a buffer
    }, $class;
}

sub get_next_item {
    my $self = shift;
    $self->reset_iterator unless defined $self->{pos};

    if (exists $self->{buf}) {
        $self->{pos}++;
        return delete $self->{buf};
    } else {
        my $row = $self->{iterate_sth}->fetchrow_arrayref;
        die "StopIteration" unless $row;
        $self->{pos}++;
        [$row->[0], $row->[1]];
    }
}

sub has_next_item {
    my $self = shift;
    $self->reset_iterator unless defined $self->{pos};

    if (exists $self->{buf}) {
        return 1;
    }
    my $row = $self->{iterate_sth}->fetchrow_arrayref;
    return 0 unless $row;
    $self->{buf} = [$row->[0], $row->[1]];
    1;
}

sub get_item_count {
    my $self = shift;
    $self->{row_count_sth}->execute;
    my ($row_count) = $self->{row_count_sth}->fetchrow_array;
    $row_count;
}

sub reset_iterator {
    my $self = shift;
    $self->{iterate_sth}->execute;
    $self->{pos} = 0;
}

sub get_iterator_pos {
    my $self = shift;
    $self->{pos};
}

sub get_item_at_pos {
    my ($self, $pos) = @_;
    $self->reset_iterator if $self->{pos} > $pos;
    while (1) {
        die "Out of range" unless $self->has_next_item;
        my $item = $self->get_next_item;
        return $item if $self->{pos} > $pos;
    }
}

sub has_item_at_pos {
    my ($self, $pos) = @_;
    return 1 if $self->{pos} > $pos;
    while (1) {
        return 0 unless $self->has_next_item;
        $self->get_next_item;
        return 1 if $self->{pos} > $pos;
    }
}

sub get_item_at_key {
    my ($self, $key) = @_;
    $self->{get_by_key_sth}->execute($key);
    my $row = $self->{get_by_key_sth}->fetchrow_arrayref;
    die "No such key '$key'" unless $row;
    $row->[0];
}

sub has_item_at_key {
    my ($self, $key) = @_;
    $self->{get_by_key_sth}->execute($key);
    my $row = $self->{get_by_key_sth}->fetchrow_arrayref;
    $row ? 1:0;
}

sub get_all_keys {
    my $self = shift;
    my @keys;
    $self->reset_iterator;
    while ($self->has_next_item) {
        my $item = $self->get_next_item;
        push @keys, $item->[0];
    }
    @keys;
}

1;
# ABSTRACT: Role to access elements from DBI

__END__