File Coverage

blib/lib/DBI/Schema/Migration.pm

Criterion	Covered	Total	%
statement	123	140	87.8
branch	24	40	60.0
condition	2	21	9.5
subroutine	22	23	95.6
pod	2	3	66.6
total	173	227	76.2

package DBI::Schema::Migration;

use 5.24.0;

use strict;
use warnings;

use feature 'say';
use English;
use Exporter 'import';

use Moo;
use Term::ANSIColor 'colored';
use File::Slurper 'read_text';
use File::Basename;
use Scalar::Util 'blessed';

use constant {
    UP   => 'up',
    DOWN => 'down',
};

our $VERSION = '1.00';

has dbh => (
    is       => 'ro',
    requires => 1,
    isa      => sub {
        if ( not blessed $_[0]
            and not $_[0]->isa('DBI::db') )
        {
            say colored( "$_[0] is not DBI::db", 'red' );
            exit;
        }
    },
);

has dir => (
    is       => 'ro',
    required => 1,
);

sub init {
    my ($self) = @_;

    my @sql = ;
    my $sql = join '', @sql;

    if ( $self->_is_applied_migrations_table_exists() ) {
        say colored( 'Table applied_migrations already exists', 'yellow' );
        return 1;
    }

    else {
        $self->dbh->do($sql)
            or say colored( $self->dbh->errstr, 'red' )
            and exit;

        say colored(
            'Table applied_migrations successfully created',
            'green'
        );

        return 1;
    }
}

sub up {
    my ( $self, $num ) = @_;

    if ( not $self->_is_applied_migrations_table_exists() ) {
        say $self->_applied_migrations_not_exist_phrase();
        exit;
    }

    $self->dbh->{AutoCommit} = 0;

    my $dir  = $self->_detect_dir;
    my @dirs = sort $self->_dir_listing($dir);

    $num = $num || @dirs;
    my $completed = 0;

    for (@dirs) {
        if ( not $num ) {
            last;
        }

        elsif ( not $self->_is_migration_applied($_) ) {
            $self->_run_migration( $dir, $_, UP );
            $completed++;
            $num--;
        }
    }

    my $rows = $self->dbh->commit;

    if ( $rows < 0 ) {
        say colored( 'Could not run migrations', 'red' ) and exit;
    }

    $self->dbh->{AutoCommit} = 1;

    say colored( "Migration up:$completed", 'green' );

    return 1;
}

sub down {
    my ( $self, $num ) = @_;

    if ( not $self->_is_applied_migrations_table_exists() ) {
        say $self->_applied_migrations_not_exist_phrase();
        exit;
    }

    $self->dbh->{AutoCommit} = 0;

    my $dir  = $self->_detect_dir;
    my @dirs = sort { $b cmp $a } $self->_dir_listing($dir);

    $num = $num || @dirs;
    my $completed = 0;

    for (@dirs) {
        if ( not $num ) {
            last;
        }

        elsif ( $self->_is_migration_applied($_) ) {
            $self->_run_migration( $dir, $_, DOWN );
            $completed++;
            $num--;
        }
    }

    my $rows = $self->dbh->commit;
    if ( $rows < 0 ) {
        say colored( 'Could not rollback migrations', 'red' );
        exit;
    }

    $self->dbh->{AutoCommit} = 1;

    say colored( "Migration down:$completed", 'green' );

    return 1;
}

sub _is_applied_migrations_table_exists {
    my ($self) = @_;

    my $sth =
        $self->dbh->table_info( '%', '%', 'applied_migrations', 'TABLE' );
    my @row = $sth->fetchrow_array;

    $sth->finish;

    return @row ? 1 : 0;
}

sub _applied_migrations_not_exist_phrase {
    return colored(
        'Table applied_migrations does not exists. You should run init first',
        'red'
    );
}

sub _detect_dir {
    my ($self) = @_;

    my @dirs = (
        $self->dir,
        $ENV{PWD} . $self->dir,
        $ENV{PWD} . '/' . $self->dir,
        $ENV{PWD} . '/' . dirname($PROGRAM_NAME) . '/' . $self->dir,
    );

    for (@dirs) {
        if ( -d $_ ) {
            return $_;
        }
    }

    say colored(
        "Dir $self->{dir} does not exists, try to specify full path",
        'red'
    );
    exit;
}

sub _dir_listing {
    my ( $self, $dir ) = @_;

    opendir my $dh, $dir
        or say colored( "Couldn't open dir '$dir': $ERRNO", 'red' )
        and exit;
    my @dirs = readdir $dh;
    closedir $dh;

    return grep { !/^\.|\.{2}$/m } @dirs;
}

sub _is_migration_applied {
    my ( $self, $migration ) = @_;

    my $sql = 'SELECT migration FROM applied_migrations WHERE migration = ?';
    my $sth = $self->dbh->prepare($sql)
        or say colored( $self->dbh->errstr, 'red' )
        and exit;
    my $rv  = $sth->execute($migration);
    my @row = $sth->fetchrow_array;

    $sth->finish;

    if ( $rv < 0 ) {
        say colored( $sth->errstr );
        exit;
    }

    return @row;
}

sub _run_migration {
    my ( $self, $dir, $migration, $type ) = @_;

    my $filename = "${migration}_$type.sql";
    my $sql      = read_text "$dir/$migration/$filename";
    my $rows     = $self->dbh->do($sql);

    if ( $rows < 0 ) {
        say colored( $self->db->errstr, 'red' );
        exit;
    }

    if ( $type eq UP ) {
        $self->_save_migration($migration);
    }
    else {
        $self->_delete_migration($migration);
    }

    return 1;
}

sub _save_migration {
    my ( $self, $migration ) = @_;

    my $sql = 'INSERT INTO applied_migrations VALUES(?)';
    my $sth = $self->dbh->prepare($sql)
        or say colored( $self->dbh->errstr, 'red' )
        and exit;
    my $rv = $sth->execute($migration);

    $sth->finish;

    return $rv ne '0E0';
}

sub _delete_migration {
    my ( $self, $migration ) = @_;

    my $sql = 'DELETE FROM applied_migrations WHERE migration = ?';
    my $sth = $self->dbh->prepare($sql)
        or say colored( $self->dbh->errstr, 'red' )
        and exit;
    my $rv = $sth->execute($migration);

    $sth->finish;

    return $rv ne '0E0';
}

1;

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