package DBIx::DBH::Legacy; use strict; use warnings; use DBI; use Params::Validate qw( :all ); our $VERSION = '0.2'; our @attr = qw ( dbi_connect_method Warn _Active _Executed _Kids _ActiveKids _CachedKids _CompatMode InactiveDestroy PrintWarn PrintError RaiseError HandleError HandleSetErr _ErrCount ShowErrorStatement TraceLevel FetchHashKeyName ChopBlanks LongReadLen LongTruncOk TaintIn TaintOut Taint Profile _should-add-support-for-private_your_module_name_* AutoCommit _Driver _Name _Statement RowCacheSize _Username ); # Preloaded methods go here. Params::Validate::validation_options(allow_extra => 1); sub connect { my @connect_data = connect_data(@_); my $dbh; eval { $dbh = DBI->connect( @connect_data ); }; die $@ if $@; die 'Unable to connect to database' unless $dbh; return $dbh; } sub dbi_attr { my ($h, %p) = @_; $h = {} unless defined $h; for my $attr (@attr) { if (exists $p{$attr}) { # warn "$attr = $p{$attr};"; $h->{$attr} = $p{$attr}; } } $h; } sub connect_data { my $class = shift; my %p = @_; my $subclass = "DBIx::DBH::$p{driver}"; eval "require $subclass"; die "unable to require $subclass to support the $p{driver} driver.\n" if $@; my ($dsn, $user, $pass, $attr) = $subclass->connect_data(@_); $attr = dbi_attr($attr, %p); ($dsn, $user, $pass, $attr) } sub form_dsn { (connect_data(@_))[0]; } 1; __END__ # Below is stub documentation for your module. You'd better edit it! =head1 NAME DBIx::DBH::Legacy - legacy helper for DBI connection data (form dsn, etc) =head1 SYNOPSIS use DBIx::DBH::Legacy; my %opt = (tty => 1) ; my %dat = ( driver => 'Pg', dbname => 'db_terry', user => 'terry', password => 'markso' ); my $dbh = DBIx::DBH::Legacy->connect(%dat, %opt) ; # yes, two hashes, not hrefs! =head1 ABSTRACT L is designed to facilitate and validate the process of creating L database connections. It's chief and unique contribution to this set of modules on CPAN is that it forms the DSN string for you, regardless of database driver. Another thing about this module is that it takes a flat Perl hash as input, making it ideal for converting HTTP form data and or config file information into DBI database handles. It also can form DSN strings for both major free databases and is subclassed to support extension for other databases. DBIx::DBH::Legacy provides rigorous validation on the input parameters via L. It does not allow parameters which are not defined by the DBI or the database driver driver into the hash. It provides support for MySQL, Postgres and Sybase (thanks to Rachel Richard for the Sybase support). =head1 Motivation This module does not appear to be very useful at first. But it has it's place. Let's see why. =head2 Simple, robust DSN formation =head3 Simple Let's take a look at a L connection string: DBI->connect("dbi:mysql:database=sakila;host=localhost;post=3306", $username, $password); Now, notice: how the C contains a lot of subelements: =over 4 =item 1. dbi =item 2. mysql =item 3. database =item 4. host =item 5. port =cut With this module, you simply specify those sub-elements in a hash: my %dat = ( driver => 'mysql', dbname => 'sakila', user => 'username', password => 'pass' ); This is much more high-level. So, the first win is that you get to be DWIM instead of DWIS. =head3 Robust This module is robust. It uses L to make sure that what you supply is valid. =head2 Easier interaction with APIs =head3 Rose::DB::register_db() expects sub-components of a DSN If you take a look at a call to C: L you will notice that it requires the sub-components of the DSN. So, ideally you would be able to keep your connection data as a set of sub-components and supply it to L but when you want to connect directly to L, you could do that also. This module is the solution for this dilemma as well. =head3 Alzabo and DBIx::AnyDBD have alternative connection syntaxes Alternative connection syntaxes such as L or L can make use of the C API call =head1 API =head2 $dbh = connect(%params) C<%params> requires the following as keys: =over 4 =item * driver : the value matches /\a(mysql|Pg)\Z/ (case-sensitive). =item * dbname : the value is the name of the database to connect to =back C<%params> can have the following optional parameters =over 4 =item * user =item * password =item * host =item * port =back C<%params> can also have parameters specific to a particular database driver. See L, L and L for additional parameters acceptable based on database driver. =head2 ($dsn, $user, $pass, $attr) = connect_data(%params) C takes the same arguments as C but returns a list of the 4 arguments required by the L C function. This is useful for working with modules that have an alternative connection syntax such as L or L. =head2 $dsn = form_dsn(%params) C takes the same arguments as C but returns only the properly formatted DSN string. This is also useful for working with modules that have an alternative connection syntax such as L or L. =head1 ADDING A DRIVER Simply add a new driver with a name of C, where C<$Driver> is a valid DBI driver name. =back =head1 SEE ALSO =over =item * L =item * L =item * L =item * L =back =head2 Links =head3 "Avoiding compound data in software and system design" L =head1 TODO =over =item * use a singleton object The current API for DBIx::DBH::Legacy requires passing in the connection data hash to each API function. The data hash should be bound to a singleton object and all methods should resource it. A good set of L roles inspired by L or L might be in order. =item * use DBIx::Connector L is an excellent module for reusing DBI database connections. This module should optionally connect to DBI via that instead of directly. =item * expose parm validation info: > > It would be nice if the parameter validation info was exposed in some > way, so that an interactive piece of software can ask a user which > driver they want, then query your module for a list of supported > parameters, then ask the user to fill them in. (Perhaps move the hash > of validation parameters to a new method named valid_params, and then > have connect_data call that method and pass the return value to > validate?) =cut =head1 AUTHOR Terrence Brannon, Ebauhaus@metaperl.comE Sybase support contributed by Rachel Richard. Mark Stosberg did all of the following: =over =item * contributed Sqlite support =item * fixed a documentation bug =item * made DBIx::DBH::Legacy more scaleable Says Mark: "Just as DBI needs no modifications for a new driver to work, neither should this module. I've attached a patch which refactors the code to address this. Rather than relying on a hardcoded list, it tries to 'require' the driver, or dies with a related error message. This could lower your own maintenance effort, as others can publish additional drivers directly without requiring a new release of DBIx::DBH::Legacy for it to work." L =back Substantial suggestions by M. Simon Ryan Cavaletto. =head1 SOURCECODE L =head1 COPYRIGHT AND LICENSE Copyright (C) by Terrence Brannon This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.4 or, at your option, any later version of Perl 5 you may have available. =cut