package VCP::DB_File; =head1 NAME VCP::DB_File - Persistant storage for id -> (name, rev_id) maps =head1 SYNOPSIS use base qw( VCP::DB_File ); =head1 DESCRIPTION By default, most VCP::Dest::* drivers keep track of the relationship between the id field assigned by the (original) VCP::Source::* driver and the final name and rev_id (or whatever fields are important to it) in the destination repository so that the previous_id fields, which refer to the original id, may be resolved when backfilling or branching. The VCP::*::revml drivers do not do this; they do not need to resolve id fields. The intent for this file is to serve as a base class so that individual sites may write their own ", ref $self, " plugins to, for instance, store this state in a RDBMS table. This is not quite offered at this time; we need to add an option to the appropriate VCP::Dest::* modules to allow the appropriate ", ref $self, " file to be loaded. To write your own ", ref $self, " file, see VCP::DB_File::sdbm. =for test_script t/01db_file.t =cut $VERSION = 1 ; use strict ; use Carp; use VCP::Debug qw( :debug ); use VCP::Utils qw( start_dir ); use fields ( 'StoreLoc', ## Where the data should be kept. 'TableName', ## database table name ); =head2 Methods =over =cut =item new VCP::DB_File::foo->new( StoreLoc => $dir, ## path to a dir to keep the state store in ); The C field indicates where the ", ref $self, " should be stored, for instance a DBI specification string or a directory to place a "revmap.db" file in. There is no control over the filename, as different storage modes may need different conventions. =cut sub new { my $class = shift ; $class = ref $class || $class ; my %options = @_; my $type = delete $options{Type} || "sdbm"; my $self = do { no strict 'refs' ; bless [ \%{"${class}::FIELDS"} ], $class; }; while ( my ( $key, $value ) = each %options ) { $self->{$key} = $value; } Carp::confess "undefined TableName" unless defined $self->{TableName}; $self->{StoreLoc} = "vcp_state" unless defined $self->{StoreLoc}; $self->{StoreLoc} = File::Spec->rel2abs( File::Spec->catdir( $self->{StoreLoc}, $self->{TableName} ), start_dir ); debug "storing ", ref $self, " in ", $self->store_loc if debugging; return $self ; } =item store_loc Gets (does not set) the StoreLoc field as an absolute path. =cut sub store_loc { my VCP::DB_File $self = shift; return $self->{StoreLoc}; } =item delete_db $db->delete_db; Deletes the persitent store. This should remove all files, lock files, etc. for filesystem stores and drop any tables for RDBMS stores. Default action is to call close_db; subclasses should (subclasses should call C<$self->SUPER::delete_db before doing anything else in their delete_db() overrides). =cut sub delete_db { my VCP::DB_File $self = shift; $self->close_db; debug "deleting ", ref $self, " in ", $self->store_loc if debugging; } =item open_db $db->open_db; Creates a new or opens an existing db. (subclasses should call C<$self->SUPER::open_db before doing anything else in their open_db() overrides). =cut sub open_db { my VCP::DB_File $self = shift; debug "opening ", ref $self, " in ", $self->store_loc if debugging; } =item close_db $db->close_db; (subclasses should call C<$self->SUPER::close_db before doing anything else in their close_db() overrides). =cut sub close_db { my VCP::DB_File $self = shift; debug "closing ", ref $self, " in ", $self->store_loc if debugging; } =item set $db->set( $key, @values ); Sets the values for $key. =cut =item get my @values = $db->get( $key ); Gets the values for $key. =item keys my @keys = $db->keys; Returns a list of ARRAY references. Each ARRAY ref is a key. =cut =back =head1 HELPER METHODS These are provided to make subclassing a tad easier =over =cut =item mkdir_store_loc $self->mkdir_store_loc; A helper method for subclasses' open_db()s to create the directory referred to by store_loc and any missing parent dirs. =cut sub mkdir_store_loc { my VCP::DB_File $self = shift; return if -e $self->store_loc; debug "making dir ", $self->store_loc if debugging; require File::Path; File::Path::mkpath( [ $self->store_loc ] ); } =item rmdir_store_loc $self->rmdir_store_loc; A helper method for subclasses' delete_db()s to remove the directory referred to by store_loc. =cut sub rmdir_store_loc { my VCP::DB_File $self = shift; return unless -e $self->store_loc; require File::Path; File::Path::rmtree( [ $self->store_loc ] ); } =item pack_values my $v = $self->pack_values( @values ); Combines the parameters in to a single string. =cut sub pack_values { shift; confess "no values to pack" unless @_; confess "can't pack undef" if grep !defined, @_; join ";", map { my $v = $_; $v =~ s/%/%%/g; $v =~ s/;/%,/; $v } @_; } =item upack_values my @v = $self->unpack_values( $v ); =cut sub unpack_values { shift; confess unless @_ == 1; my @v = split /;/, "$_[0];", -1; pop @v; @v = map { s/%%/%/g; s/%,/;/g; $_ } @v; return @v; } =back =head1 AUTHOR Barrie Slaymaker =head1 COPYRIGHT Copyright (c) 2000, 2001, 2002 Perforce Software, Inc. All rights reserved. See L (C) for the terms of use. =cut 1