File Coverage

blib/lib/Mojolicious/Plugin/QuickPg.pm

Criterion	Covered	Total	%
statement	4	6	66.6
branch			n/a
condition			n/a
subroutine	2	2	100.0
pod			n/a
total	6	8	75.0

package Mojolicious::Plugin::QuickPg;
use Mojo::Base 'Mojolicious::Plugin';

use Mojo::Pg;
use Carp;

our $VERSION = '1.5';
our $Debug = 0;
has pg => sub { +{} };

sub register {
    my ($plugin, $app, $conf) = @_;
    my $version = undef;
    croak qq{DSN is empty! See perldoc...\n} unless $conf->{dsn};

    $plugin->pg(Mojo::Pg->new($conf->{dsn}));
    $Debug = $conf->{debug};

    eval {
      $version =  $plugin->pg->db->query('select version()')->hash;
    };
    croak qq{Invalid dsn: $@ \n} if $@;
    $app->log->info($version->{version}) if ($conf->{debug});

    $app->helper( qselect => sub {$plugin->_quick_select(@_)});
    $app->helper( qinsert => sub {$plugin->_quick_insert(@_)});
    $app->helper( qupdate => sub {$plugin->_quick_update(@_)});
    $app->helper( qdelete => sub {$plugin->_quick_delete(@_)});
    $app->helper( qcount  => sub {$plugin->_quick_count(@_)});
    $app->helper( qcustom => sub {
        my ($self, $sql, @params) = @_;
        eval {
            local $SIG{__WARN__} = sub {};
            return $plugin->pg->db->query($sql,@params);
        };

        });
    $app->helper( qerror  => sub { return $@ });
}

sub _quick_insert {
    my ($plugin, $self, $table_name, $data) = @_;
    return $plugin->_quick_query('INSERT', $table_name, $data);
}

#
sub _quick_update {
    my ($plugin, $self, $table_name, $where, $data) = @_;
    return $plugin->_quick_query('UPDATE', $table_name, $data, $where);
}
#
#
sub _quick_delete {
    my ($plugin, $self, $table_name, $where) = @_;
    return $plugin->_quick_query('DELETE', $table_name, undef, $where);
}

sub _quick_select {
    my ($plugin, $self, $table_name, $where, $opts) = @_;
    $where = $where || {};
    return $plugin->_quick_query('SELECT', $table_name, $opts, $where);
}


sub _quick_count {
    my ($plugin, $self, $table_name, $where) = @_;
    $where = $where || {};
    my $opts = {}; #Options are irrelevant for a count.
    return $plugin->_quick_query('COUNT', $table_name, $opts, $where);
}

#############
sub _quick_query {
    my ($self, $type, $table_name, $data, $where) = @_;
    # Basic sanity checks first...
    if ($type !~ m{^ (SELECT|INSERT|UPDATE|DELETE|COUNT) $}x) {
        carp "Unrecognised query type $type!";
        return;
    }
    if (!$table_name || ref $table_name) {
        carp "Expected table name as a straight scalar";
        return;
    }
    if (($type eq 'INSERT' || $type eq 'UPDATE')
        && (!$data || ref $data ne 'HASH'))
    {
        carp "Expected a hashref of changes";
        return;
    }
    if (($type =~ m{^ (SELECT|UPDATE|DELETE|COUNT) $}x)
        && (!$where)) {
        carp "Expected where conditions";
        return;
    }

    my ($sql, @bind_params) = $self->_generate_sql(
        $type, $table_name, $data, $where
    );
    say $sql if $Debug;

    if ($type eq 'SELECT') {
        return $self->pg->db->query($sql, @bind_params)->hash unless wantarray;
        return $self->pg->db->query($sql, @bind_params)->hashes->to_array;
    } elsif ($type eq 'COUNT') {
        my $row = $self->pg->db->query($sql, @bind_params)->hash;
        return $row->{count};
    } else {
        # INSERT (default field name = id)
        if ($type eq 'INSERT') {
        # get primary key from table
        my $PK = 'id'; # default PK column is 'id'
        my $pkey =  $self->pg->db->query(qq{SELECT a.attname FROM pg_index i JOIN pg_attribute a ON a.attrelid = i.indrelid
                                         AND a.attnum = ANY(i.indkey) WHERE  i.indrelid = '$table_name'::regclass AND i.indisprimary
                                         ORDER BY a.attnum DESC});
        # if id exists in PKeys get it, else - get last elem
        while (my $next = $pkey->hash) {
             if ( $next->{attname} eq 'id' ) {
                $PK = $next->{attname};
                # Note that "finish" needs to be called if you are not fetching all the possible rows
                $pkey->finish;
                last;
             }
             else {
                $PK = $next->{attname};
             }
        }

        $sql .= ' returning ' . $PK;

            eval {
            return $self->pg->db->query($sql, @bind_params)->hash->{$PK};
            };
        } else {
        # delete/update
            eval {
            return $self->pg->db->query($sql, @bind_params)->rows;
            };
        }

    }
}

sub _generate_sql {
    my ($self, $type, $table_name, $data, $where) = @_;

    my $which_cols = '*';
    my $opts = $type eq 'SELECT' && $data ? $data : {};
    if ($opts->{columns}) {
        my @cols = (ref $opts->{columns})
            ? @{ $opts->{columns} }
            :    $opts->{columns} ;
        $which_cols = join(',', map { $self->_quote_identifier($_) } @cols);
    }

    $table_name = $self->_quote_identifier($table_name);
    my @bind_params;

    my $sql = {
        SELECT => "SELECT $which_cols FROM $table_name",
        INSERT => "INSERT INTO $table_name ",
        UPDATE => "UPDATE $table_name SET ",
        DELETE => "DELETE FROM $table_name ",
        COUNT => "SELECT COUNT(*) FROM $table_name",
    }->{$type};

    if ($type eq 'INSERT') {
        my (@keys, @values);
        for my $key (sort keys %$data) {
            my $value = $data->{$key};
            push @keys, $self->_quote_identifier($key);
            if (ref $value eq 'SCALAR') {
                # If it's a scalarref it goes in the SQL as it is; this is a
                # potential SQL injection risk, but is documented as such - it
                # allows the user to include arbitrary SQL, at their own risk.
                push @values, $$value;
            } else {
                push @values, "?";
                push @bind_params, $value;
            }
        }

        $sql .= sprintf "(%s) VALUES (%s)",
            join(',', @keys), join(',', @values);
    }

    if ($type eq 'UPDATE') {
        my @sql;
        for (sort keys %$data) {
          push @sql, $self->_quote_identifier($_) . '=' .
            (ref $data->{$_} eq 'SCALAR' ? ${$data->{$_}} : "?");
          push @bind_params, $data->{$_} if (ref $data->{$_} ne 'SCALAR');
        }
        $sql .= join ',', @sql;
    }

    if ($type eq 'UPDATE' || $type eq 'DELETE' || $type eq 'SELECT' || $type eq 'COUNT')
    {
        if ($where && !ref $where) {
            $sql .= " WHERE " . $where;
        } elsif ( ref $where eq 'HASH' ) {
            my @stmts;
            foreach my $k ( sort keys %$where ) {
                my $v = $where->{$k};
                if ( ref $v eq 'HASH' ) {
                    my $not = delete $v->{'not'};
                    while (my($op,$value) = each %$v ) {
                        my ($cond, $add_bind_param)
                            = $self->_get_where_sql($op, $not, $value);
                        push @stmts, $self->_quote_identifier($k) . $cond;
                        push @bind_params, $v->{$op} if $add_bind_param;
                    }
                } else {
                    my $clause .= $self->_quote_identifier($k);
                    if ( ! defined $v ) {
                        $clause .= ' IS NULL';
                    }
                    elsif ( ! ref $v ) {
                        $clause .= '=?';
                        push @bind_params, $v;
                    }
                    elsif ( ref $v eq 'ARRAY' ) {
                        $clause .= ' IN (' . (join ',', map { '?' } @$v) . ')';
                        push @bind_params, @$v;
                    }
                    push @stmts, $clause;
                }
            }
            $sql .= " WHERE " . join " AND ", @stmts if keys %$where;
        } elsif (ref $where) {
            carp "Can't handle ref " . ref $where . " for where";
            return;
        }
    }

    # Add an ORDER BY clause, if we want to:
    if (exists $opts->{order_by} and defined $opts->{order_by}) {
        $sql .= ' ' . $self->_build_order_by_clause($opts->{order_by});
    }


    # Add a LIMIT clause if we want to:
    if (exists $opts->{limit} and defined $opts->{limit}) {
        my $limit = $opts->{limit};
        $limit =~ s/\s+//g;
        # Check the limit clause is sane - just a number, or two numbers with a
        # comma between (if using offset,limit )
        if ($limit =~ m{ ^ \d+ (?: , \d+)? $ }x) {
            # Checked for sanity above so safe to interpolate
            $sql .= " LIMIT $limit";
        } else {
            die "Invalid LIMIT param $opts->{limit} !";
        }
    } elsif ($type eq 'SELECT' && !wantarray) {
        # We're only returning one row in scalar context, so don't ask for any
        # more than that
        $sql .= " LIMIT 1";
    }

    if (exists $opts->{offset} and defined $opts->{offset}) {
        my $offset = $opts->{offset};
        $offset =~ s/\s+//g;
        if ($offset =~ /^\d+$/) {
            $sql .= " OFFSET $offset";
        } else {
            die "Invalid OFFSET param $opts->{offset} !";
        }
    }
    return ($sql, @bind_params);
}

sub _get_where_sql {
    my ($self, $op, $not, $value) = @_;

    $op = lc $op;

    # "IS" needs special-casing, as it will be either "IS NULL" or "IS NOT NULL"
    # - there's no need to return a bind param for that.
    if ($op eq 'is') {
        return $not ? 'IS NOT NULL' : 'IS NULL';
    }

    my %st = (
        'like' => ' LIKE ?',
        'is' => ' IS ?',
        'ge' => ' >= ?',
        'gt' => ' > ?',
        'le' => ' <= ?',
        'lt' => ' < ?',
        'eq' => ' = ?',
        'ne' => ' != ?',
    );

    # Return the appropriate SQL, and indicate that the value should be added to
    # the bind params
    return (($not ? ' NOT' . $st{$op} : $st{$op}), 1);
}

# Given either a column name, or a hashref of e.g. { asc => 'colname' },
# or an arrayref of either, construct an ORDER BY clause (quoting col names)
# e.g.:
# 'foo'              => ORDER BY foo
# { asc => 'foo' }   => ORDER BY foo ASC
# ['foo', 'bar']     => ORDER BY foo, bar
# [ { asc => 'foo' }, { desc => 'bar' } ]
#      => 'ORDER BY foo ASC, bar DESC
sub _build_order_by_clause {
    my ($self, $in) = @_;

    # Input could be a straight scalar, or a hashref, or an arrayref of either
    # straight scalars or hashrefs.  Turn a straight scalar into an arrayref to
    # avoid repeating ourselves.
    $in = [ $in ] unless ref $in eq 'ARRAY';

    # Now, for each of the fields given, add them to the clause
    my @sort_fields;
    for my $field (@$in) {
        if (!ref $field) {
            push @sort_fields, $self->_quote_identifier($field);
        } elsif (ref $field eq 'HASH') {
            my ($order, $name) = %$field;
            $order = uc $order;
            if ($order ne 'ASC' && $order ne 'DESC') {
                die "Invalid sort order $order used in order_by option!";
            }
            # $order has been checked to be 'ASC' or 'DESC' above, so safe to
            # interpolate
            push @sort_fields, $self->_quote_identifier($name) . " $order";
        }
    }

    return "ORDER BY " . join ', ', @sort_fields;
}

# A wrapper around DBI's quote_identifier which first splits on ".", so that
# e.g. database.table gets quoted as `database`.`table`, not `database.table`
sub _quote_identifier {
    my ($self, $identifier) = @_;
    return join '.', map {
        $self->pg->db->dbh->quote_identifier($_)
    } split /\./, $identifier;
}

1;
__END__