From: John Napiorkowski Date: Thu, 17 Apr 2008 13:41:17 +0000 (+0000) Subject: - added tests to replication to make sure dbd::multi fails over when a dtabase is... X-Git-Tag: v0.08240~487 X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=0f83441a23e70b5b9e68ae3002cc63b8cf4e8698;p=dbsrgits%2FDBIx-Class.git - added tests to replication to make sure dbd::multi fails over when a dtabase is forcible disconnected - updated DBIC::DBI::Replication so that in addition to a dsn string, you can pass a preexisting database handle. --- diff --git a/lib/DBIx/Class/Storage/DBI/Replication.pm b/lib/DBIx/Class/Storage/DBI/Replication.pm index 36e8b24..6ec74e9 100644 --- a/lib/DBIx/Class/Storage/DBI/Replication.pm +++ b/lib/DBIx/Class/Storage/DBI/Replication.pm @@ -21,6 +21,8 @@ DBIx::Class::Storage::DBI::Replication - EXPERIMENTAL Replicated database suppor [ "dbi:mysql:database=test;hostname=master", "username", "password", { AutoCommit => 1 } ], # master [ "dbi:mysql:database=test;hostname=slave1", "username", "password", { priority => 10 } ], # slave1 [ "dbi:mysql:database=test;hostname=slave2", "username", "password", { priority => 10 } ], # slave2 + [ $dbh, '','', {priority=>10}], # add in a preexisting database handle + [ sub { DBI->connect }, '', '', {priority=>10}], # DBD::Multi will call this coderef for connects <...>, { limit_dialect => 'LimitXY' } # If needed, see below ] ); @@ -83,15 +85,24 @@ sub connect_info { $global_options = ref $info->[-1] eq 'HASH' ? pop( @$info ) : {}; if( ref( $options = $info->[0]->[-1] ) eq 'HASH' ) { # Local options present in dsn, merge them with global options - map { $global_options->{$_} = $options->{$_} } keys %$options; - pop @{$info->[0]}; + map { $global_options->{$_} = $options->{$_} } keys %$options; + pop @{$info->[0]}; } # We need to copy-pass $global_options, since connect_info clears it while # processing options $self->write_source->connect_info( @{$info->[0]}, { %$global_options } ); - @dsns = map { ($_->[3]->{priority} || 10) => $_ } @{$info->[0]}[1..@{$info->[0]}-1]; + ## allow either a DSN string or an already connect $dbh. Just remember if + ## you use the $dbh option then DBD::Multi has no idea how to reconnect in + ## the event of a failure. + + @dsns = map { + ## if the first element in the arrayhash is a ref, make that the value + my $db = ref $_->[0] ? $_->[0] : $_; + ($_->[3]->{priority} || 10) => $db; + } @{$info->[0]}[1..@{$info->[0]}-1]; + $global_options->{dsns} = \@dsns; $self->read_source->connect_info( [ 'dbi:Multi:', undef, undef, { %$global_options } ] ); diff --git a/t/93storage_replication.t b/t/93storage_replication.t index 67b09c2..fd2241d 100644 --- a/t/93storage_replication.t +++ b/t/93storage_replication.t @@ -1,69 +1,266 @@ use strict; use warnings; use lib qw(t/lib); - -use File::Copy; - -use DBICTest; - use Test::More; +use Data::Dump qw/dump/; BEGIN { eval "use DBD::Multi"; plan $@ ? ( skip_all => 'needs DBD::Multi for testing' ) - : ( tests => 3 ); + : ( tests => 18 ); +} + +## ---------------------------------------------------------------------------- +## Build a class to hold all our required testing data and methods. +## ---------------------------------------------------------------------------- + +TESTSCHEMACLASS: { + + package DBIx::Class::DBI::Replication::TestReplication; + + use DBI; + use DBICTest; + use File::Copy; + + ## Create a constructor + + sub new { + my $class = shift @_; + my %params = @_; + + my $self = bless { + db_paths => $params{db_paths}, + dsns => $class->init_dsns(%params), + schema=>$class->init_schema, + }, $class; + + $self->connect; + return $self; + } + + ## get the DSNs. We build this up from the list of file paths + + sub init_dsns { + my $class = shift @_; + my %params = @_; + my $db_paths = $params{db_paths}; + + my @dsn = map { + "dbi:SQLite:${_}"; + } @$db_paths; + + return \@dsn; + } + + ## get the Schema and set the replication storage type + + sub init_schema { + my $class = shift @_; + my $schema = DBICTest->init_schema(); + $schema->storage_type( '::DBI::Replication' ); + + return $schema; + } + + ## connect the Schema + + sub connect { + my $self = shift @_; + my ($master, @slaves) = @{$self->{dsns}}; + my @connections = ([$master, '','', {AutoCommit=>1, PrintError=>0}]); + my @slavesob; + + foreach my $slave (@slaves) + { + my $dbh = shift @{$self->{slaves}} + || DBI->connect($slave,"","",{PrintError=>0, PrintWarn=>0}); + + push @connections, + [$dbh, '','',{priority=>10}]; + + push @slavesob, + $dbh; + } + + ## Keep track of the created slave databases + $self->{slaves} = \@slavesob; + + $self + ->{schema} + ->connect([ + @connections, + {limit_dialect => 'LimitXY'} + ]); + } + + ## replication + + sub replicate { + my $self = shift @_; + my ($master, @slaves) = @{$self->{db_paths}}; + + foreach my $slave (@slaves) { + copy($master, $slave); + } + } + + ## Cleanup afer ourselves. + + sub cleanup { + my $self = shift @_; + my ($master, @slaves) = @{$self->{db_paths}}; + + foreach my $slave (@slaves) { + unlink $slave; + } + } + + ## Force a reconnection + + sub reconnect { + my $self = shift @_; + my $schema = $self->connect; + $self->{schema} = $schema; + return $schema; + } } -my $schema = DBICTest->init_schema(); - -$schema->storage_type( '::DBI::Replication' ); - - -my $db_file1 = "t/var/DBIxClass.db"; -my $db_file2 = "t/var/DBIxClass_slave1.db"; -my $db_file3 = "t/var/DBIxClass_slave2.db"; -my $dsn1 = $ENV{"DBICTEST_DSN"} || "dbi:SQLite:${db_file1}"; -my $dsn2 = $ENV{"DBICTEST_DSN2"} || "dbi:SQLite:${db_file2}"; -my $dsn3 = $ENV{"DBICTEST_DSN3"} || "dbi:SQLite:${db_file3}"; - -$schema->connect( [ - [ $dsn1, '', '', { AutoCommit => 1 } ], - [ $dsn2, '', '', { priority => 10 } ], - [ $dsn3, '', '', { priority => 10 } ] - ] - ); - -$schema->populate('Artist', [ - [ qw/artistid name/ ], - [ 4, 'Ozric Tentacles'] - ]); - -my $new_artist1 = $schema->resultset('Artist')->find(4); - -isa_ok ($new_artist1, 'DBICTest::Artist'); - -# reconnect -my $schema2 = $schema->connect( [ - [ $dsn1, '', '', { AutoCommit => 1 } ], - [ $dsn2, '', '', { priority => 10 } ], - [ $dsn3, '', '', { priority => 10 } ] - ] - ); - -# try and read (should fail) -eval { my $new_artist2 = $schema2->resultset('Artist')->find(4); }; -ok($@, 'read after disconnect fails because it uses slave 1 which we have neglected to "replicate" yet'); - -# try and read (should succede after faked synchronisation) -copy($db_file1, $db_file2); -$schema2 = $schema->connect( [ - [ $dsn1, '', '', { AutoCommit => 1 } ], - [ $dsn2, '', '', { priority => 10 } ], - [ $dsn3, '', '', { priority => 10 } ] - ] - ); -my $new_artist3 = $schema2->resultset('Artist')->find(4); -isa_ok ($new_artist3, 'DBICTest::Artist'); - -unlink $db_file2; +## ---------------------------------------------------------------------------- +## Create an object and run some tests +## ---------------------------------------------------------------------------- + +my %params = ( + db_paths => [ + "t/var/DBIxClass.db", + "t/var/DBIxClass_slave1.db", + "t/var/DBIxClass_slave2.db", + ], +); + +ok my $replicate = DBIx::Class::DBI::Replication::TestReplication->new(%params) + => 'Created a replication object'; + +isa_ok $replicate->{schema} + => 'DBIx::Class::Schema'; + +## Add some info to the database + +$replicate + ->{schema} + ->populate('Artist', [ + [ qw/artistid name/ ], + [ 4, "Ozric Tentacles"], + ]); + +## Make sure all the slaves have the table definitions + +$replicate->replicate; + +## Make sure we can read the data. + +ok my $artist1 = $replicate->{schema}->resultset('Artist')->find(4) + => 'Created Result'; + +isa_ok $artist1 + => 'DBICTest::Artist'; + +is $artist1->name, 'Ozric Tentacles' + => 'Found expected name for first result'; + +## Add some new rows that only the master will have This is because +## we overload any type of write operation so that is must hit the master +## database. + +use Fcntl qw (:flock); + +my $master_path = $replicate->{db_paths}->[0]; +open LOCKFILE, ">>$master_path" + or die "Cannot open $master_path"; +flock(LOCKFILE, LOCK_EX); + +$replicate + ->{schema} + ->populate('Artist', [ + [ qw/artistid name/ ], + [ 5, "Doom's Children"], + [ 6, "Dead On Arrival"], + [ 7, "Watergate"], + ]); + +## Reconnect the database +$replicate->reconnect; + +## Alright, the database 'cluster' is not in a consistent state. When we do +## a read now we expect bad news + +is $replicate->{schema}->resultset('Artist')->find(5), undef + => 'read after disconnect fails because it uses slave 1 which we have neglected to "replicate" yet'; + +## Make sure all the slaves have the table definitions +$replicate->replicate; + +## Should find some data now + +ok my $artist2 = $replicate->{schema}->resultset('Artist')->find(5) + => 'Sync succeed'; + +isa_ok $artist2 + => 'DBICTest::Artist'; + +is $artist2->name, "Doom's Children" + => 'Found expected name for first result'; + +## What happens when we delete one of the slaves? + +ok my $slave1 = @{$replicate->{slaves}}[0] + => 'Got Slave1'; + +ok $slave1->disconnect + => 'disconnected slave1'; + +$replicate->reconnect; + +ok my $artist3 = $replicate->{schema}->resultset('Artist')->find(6) + => 'Still finding stuff.'; + +isa_ok $artist3 + => 'DBICTest::Artist'; + +is $artist3->name, "Dead On Arrival" + => 'Found expected name for first result'; + +## Let's delete all the slaves + +ok my $slave2 = @{$replicate->{slaves}}[1] + => 'Got Slave2'; + +ok $slave2->disconnect + => 'Disconnected slave2'; + +$replicate->reconnect; + +## We expect an error now, since all the slaves are dead + +eval { + $replicate->{schema}->resultset('Artist')->find(4)->name; +}; + +ok $@ => 'Got error when trying to find artistid 4'; + +## This should also be an error + +eval { + my $artist4 = $replicate->{schema}->resultset('Artist')->find(7); +}; + +ok $@ => 'Got read errors after everything failed'; + +## Delete the old database files +$replicate->cleanup; + + + + + +