NAME

Test::Database::Driver - Base class for Test::Database drivers

SYNOPSIS

    package Test::Database::Driver::MyDatabase;
    use strict;
    use warnings;

    use Test::Database::Driver;
    our @ISA = qw( Test::Database::Driver );

    sub _version {
        my ($class) = @_;
        ...;
        return $version;
    }

    sub create_database {
        my ( $self ) = @_;
        ...;
        return $handle;
    }

    sub drop_database {
        my ( $self, $name ) = @_;
        ...;
    }

    sub databases {
        my ($self) = @_;
        ...;
        return @databases;
    }

DESCRIPTION

Test::Database::Driver is a base class for creating Test::Database drivers.

METHODS

The class provides the following methods:

new

    my $driver = Test::Database::Driver->new( driver => 'SQLite' );

    my $driver = Test::Database::Driver::SQLite->new();

Create a new Test::Database::Driver object.

If called as "Test::Database::Driver->new()", requires a "driver" parameter to define the actual object class.

make_handle

    my $handle = $driver->make_handle();

Create a new Test::Database::Handle object, attached to an existing database or to a newly created one.

The decision whether to create a new database or not is made by Test::Database::Driver based on the information in the mapper. See "TEMPORARY STORAGE ORGANIZATION" for details.

make_dsn

    my $dsn = $driver->make_dsn( %args )

Return a Data Source Name based on the driver's DSN, with the key/value pairs contained in %args as additional parameters.

This is typically used by "dsn()" to make a DSN for a specific database, based on the driver's DSN.

name

dbd

    my $name = $driver->dbd;

The driver's short name (everything after "Test::Database::Driver::").

base_dir

    my $dir = $driver->base_dir;

The directory where the driver should store all the files for its databases, if needed. Typically used by file-based database drivers.

version

    my $db_version = $driver->version;

"version" object representing the version of the underlying database enginge. This object is build with the return value of "_version()".

version_string

    my $db_version = $driver->version_string;

Version string representing the version of the underlying database enginge. This string is the actual return value of "_version()".

dbd_version

    my $dbd_version = $driver->dbd_version;

The version of the DBD used to connect to the database engine, as returned by "VERSION()".

driver_dsn

    my $dsn = $driver->driver_dsn;

Return a driver Data Source Name, sufficient to connect to the database engine without specifying an actual database.

username

    my $username = $driver->username;

Return the connection username. Defaults to "undef".

password

    my $password = $driver->password;

Return the connection password. Defaults to "undef".

connection_info()

    my @info = $driver->connection_info;

Return the connection information triplet ("driver_dsn", "username", "password").

version_matches

    if ( $driver->version_matches($request) ) {
        ...;
    }

Return a boolean indicating if the driver's version matches the version constraints in the given request (see Test::Database documentation's section about requests).

METHODS FOR DRIVER AUTHORS

The class also provides a few helpful commands that may be useful for driver authors:

available_dbname

    my $dbname = $self->available_dbname();

Return an unused database name that can be used to create a new database for the driver.

dsn

    my $dns = $self->dsn( $dbname )

Build a Data Source Name for the database with the given $dbname, based on the driver's DSN.

WRITING A DRIVER FOR YOUR DATABASE OF CHOICE

The SYNOPSIS contains a good template for writing a Test::Database::Driver class.

Creating a driver requires writing the following methods:

_version

    my $version = $driver->_version;

Return the version of the underlying database engine.

create_database

    $driver->create_database( $name );

Create the database for the corresponding DBD driver.

Return a Test::Database::Handle in case of success, and nothing in case of failure to create the database.

drop_database( $name )

    $driver->drop_database( $name );

Drop the database named $name.

OVERRIDABLE METHODS WHEN WRITING A DRIVER

Some methods have defaults implementations in Test::Database::Driver, but those can be overridden in the derived class:

is_filebased

Return a boolean value indicating if the database engine is file-based or not, i.e. if all the database information is stored in a file or a directory, and no external database server is needed.

databases

    my @db = $driver->databases();

Return the names of all existing databases for this driver as a list (the default implementation is only valid for file-based drivers).

TEMPORARY STORAGE ORGANIZATION

Subclasses of Test::Database::Driver store useful information in the system's temporary directory, under a directory named Test-Database-$user ($user being the current user's name).

That directory contains the following files:

database files: The database files and directories created by file-based drivers controlled by Test::Database are stored here, under names matching tdd_ DRIVER_N, where DRIVER is the lowercased name of the driver and N is a number.
the mapping.yml file: A YAML file containing a "cwd()" / database name mapping, to enable a given test suite to receive the same database handles in all the test scripts that call the "Test::Database->handles()" method.

AUTHOR

Philippe Bruhat (BooK), "<book@cpan.org>"

COPYRIGHT

LICENSE

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.