93storage_replication.t

use strict;
use warnings;
use lib qw(t/lib);
use Test::More;
use Test::Exception;
use DBICTest;
use List::Util 'first';
use Scalar::Util 'reftype';
use IO::Handle;

BEGIN {
    eval "use DBIx::Class::Storage::DBI::Replicated; use Test::Moose";
    plan $@
        ? ( skip_all => "Deps not installed: $@" )
        : ( tests => 90 );
}

use_ok 'DBIx::Class::Storage::DBI::Replicated::Pool';
use_ok 'DBIx::Class::Storage::DBI::Replicated::Balancer';
use_ok 'DBIx::Class::Storage::DBI::Replicated::Replicant';
use_ok 'DBIx::Class::Storage::DBI::Replicated';

=head1 HOW TO USE

    This is a test of the replicated storage system.  This will work in one of
    two ways, either it was try to fake replication with a couple of SQLite DBs
    and creative use of copy, or if you define a couple of %ENV vars correctly
    will try to test those.  If you do that, it will assume the setup is properly
    replicating.  Your results may vary, but I have demonstrated this to work with
    mysql native replication.
    
=cut


## ----------------------------------------------------------------------------
## Build a class to hold all our required testing data and methods.
## ----------------------------------------------------------------------------

TESTSCHEMACLASSES: {

    ## --------------------------------------------------------------------- ##
    ## Create an object to contain your replicated stuff.
    ## --------------------------------------------------------------------- ##
    
    package DBIx::Class::DBI::Replicated::TestReplication;
   
    use DBICTest;
    use base qw/Class::Accessor::Fast/;
    
    __PACKAGE__->mk_accessors( qw/schema/ );

    ## Initialize the object
    
	sub new {
	    my ($class, $schema_method) = (shift, shift);
	    my $self = $class->SUPER::new(@_);
	
	    $self->schema( $self->init_schema($schema_method) );
	    return $self;
	}
    
    ## Get the Schema and set the replication storage type
    
    sub init_schema {
        # current SQLT SQLite producer does not handle DROP TABLE IF EXISTS, trap warnings here
        local $SIG{__WARN__} = sub { warn @_ unless $_[0] =~ /no such table.+DROP TABLE/ };

        my ($class, $schema_method) = @_;

        my $method = "get_schema_$schema_method";
        my $schema = $class->$method;

        return $schema;
    }

    sub get_schema_by_storage_type {
      DBICTest->init_schema(
        sqlite_use_file => 1,
        storage_type=>{
          '::DBI::Replicated' => {
            balancer_type=>'::Random',
            balancer_args=>{
              auto_validate_every=>100,
	      master_read_weight => 1
            },
          }
        },
        deploy_args=>{
          add_drop_table => 1,
        },
      );
    }

    sub get_schema_by_connect_info {
      DBICTest->init_schema(
        sqlite_use_file => 1,
        storage_type=> '::DBI::Replicated',
        balancer_type=>'::Random',
        balancer_args=> {
          auto_validate_every=>100,
	  master_read_weight => 1
        },
        deploy_args=>{
          add_drop_table => 1,
        },
      );
    }

    sub generate_replicant_connect_info {}
    sub replicate {}
    sub cleanup {}

    ## --------------------------------------------------------------------- ##
    ## Add a connect_info option to test option merging.
    ## --------------------------------------------------------------------- ##
    {
    package DBIx::Class::Storage::DBI::Replicated;

    use Moose;

    __PACKAGE__->meta->make_mutable;

    around connect_info => sub {
      my ($next, $self, $info) = @_;
      $info->[3]{master_option} = 1;
      $self->$next($info);
    };

    __PACKAGE__->meta->make_immutable;

    no Moose;
    }
  
    ## --------------------------------------------------------------------- ##
    ## Subclass for when you are using SQLite for testing, this provides a fake
    ## replication support.
    ## --------------------------------------------------------------------- ##
        
    package DBIx::Class::DBI::Replicated::TestReplication::SQLite;

    use DBICTest;
    use File::Copy;    
    use base 'DBIx::Class::DBI::Replicated::TestReplication';
    
    __PACKAGE__->mk_accessors( qw/master_path slave_paths/ );
    
    ## Set the mastep path from DBICTest
    
	sub new {
	    my $class = shift @_;
	    my $self = $class->SUPER::new(@_);
	
	    $self->master_path( DBICTest->_sqlite_dbfilename );
	    $self->slave_paths([
            "t/var/DBIxClass_slave1.db",
            "t/var/DBIxClass_slave2.db",    
        ]);
        
	    return $self;
	}    
	
    ## Return an Array of ArrayRefs where each ArrayRef is suitable to use for
    ## $storage->connect_info to be used for connecting replicants.
    
    sub generate_replicant_connect_info {
        my $self = shift @_;
        my @dsn = map {
            "dbi:SQLite:${_}";
        } @{$self->slave_paths};
        
        my @connect_infos = map { [$_,'','',{AutoCommit=>1}] } @dsn;

    # try a hashref too
        my $c = $connect_infos[0];
        $connect_infos[0] = {
          dsn => $c->[0],
          user => $c->[1],
          password => $c->[2],
          %{ $c->[3] }
        };

        @connect_infos
    }

    ## Do a 'good enough' replication by copying the master dbfile over each of
    ## the slave dbfiles.  If the master is SQLite we do this, otherwise we
    ## just do a one second pause to let the slaves catch up.
    
    sub replicate {
        my $self = shift @_;
        foreach my $slave (@{$self->slave_paths}) {
            copy($self->master_path, $slave);
        }
    }
    
    ## Cleanup after ourselves.  Unlink all gthe slave paths.
    
    sub cleanup {
        my $self = shift @_;
        foreach my $slave (@{$self->slave_paths}) {
            unlink $slave;
        }     
    }
    
    ## --------------------------------------------------------------------- ##
    ## Subclass for when you are setting the databases via custom export vars
    ## This is for when you have a replicating database setup that you are
    ## going to test against.  You'll need to define the correct $ENV and have
    ## two slave databases to test against, as well as a replication system
    ## that will replicate in less than 1 second.
    ## --------------------------------------------------------------------- ##
        
    package DBIx::Class::DBI::Replicated::TestReplication::Custom; 
    use base 'DBIx::Class::DBI::Replicated::TestReplication';
    
    ## Return an Array of ArrayRefs where each ArrayRef is suitable to use for
    ## $storage->connect_info to be used for connecting replicants.
    
    sub generate_replicant_connect_info { 
        return (
            [$ENV{"DBICTEST_SLAVE0_DSN"}, $ENV{"DBICTEST_SLAVE0_DBUSER"}, $ENV{"DBICTEST_SLAVE0_DBPASS"}, {AutoCommit => 1}],
            [$ENV{"DBICTEST_SLAVE1_DSN"}, $ENV{"DBICTEST_SLAVE1_DBUSER"}, $ENV{"DBICTEST_SLAVE1_DBPASS"}, {AutoCommit => 1}],           
        );
    }
    
    ## pause a bit to let the replication catch up 
    
    sub replicate {
    	sleep 1;
    } 
}

## ----------------------------------------------------------------------------
## Create an object and run some tests
## ----------------------------------------------------------------------------

## Thi first bunch of tests are basic, just make sure all the bits are behaving

my $replicated_class = DBICTest->has_custom_dsn ?
    'DBIx::Class::DBI::Replicated::TestReplication::Custom' :
    'DBIx::Class::DBI::Replicated::TestReplication::SQLite';

my $replicated;

for my $method (qw/by_connect_info by_storage_type/) {
  ok $replicated = $replicated_class->new($method)
      => "Created a replication object $method";
      
  isa_ok $replicated->schema
      => 'DBIx::Class::Schema';
      
  isa_ok $replicated->schema->storage
      => 'DBIx::Class::Storage::DBI::Replicated';

  isa_ok $replicated->schema->storage->balancer
      => 'DBIx::Class::Storage::DBI::Replicated::Balancer::Random'
      => 'configured balancer_type';
}

ok $replicated->schema->storage->meta
    => 'has a meta object';
    
isa_ok $replicated->schema->storage->master
    => 'DBIx::Class::Storage::DBI';
    
isa_ok $replicated->schema->storage->pool
    => 'DBIx::Class::Storage::DBI::Replicated::Pool';
    
does_ok $replicated->schema->storage->balancer
    => 'DBIx::Class::Storage::DBI::Replicated::Balancer'; 

ok my @replicant_connects = $replicated->generate_replicant_connect_info
    => 'got replication connect information';

ok my @replicated_storages = $replicated->schema->storage->connect_replicants(@replicant_connects)
    => 'Created some storages suitable for replicants';

ok my @all_storages = $replicated->schema->storage->all_storages
    => '->all_storages';

is scalar @all_storages,
    3
    => 'correct number of ->all_storages';

is ((grep $_->isa('DBIx::Class::Storage::DBI'), @all_storages),
    3
    => '->all_storages are correct type');

my @all_storage_opts =
  grep { (reftype($_)||'') eq 'HASH' }
    map @{ $_->_connect_info }, @all_storages;

is ((grep $_->{master_option}, @all_storage_opts),
    3
    => 'connect_info was merged from master to replicants');
 
my @replicant_names = keys %{ $replicated->schema->storage->replicants };

## Silence warning about not supporting the is_replicating method if using the
## sqlite dbs.
$replicated->schema->storage->debugobj->silence(1)
  if first { m{^t/} } @replicant_names;
   
isa_ok $replicated->schema->storage->balancer->current_replicant
    => 'DBIx::Class::Storage::DBI'; 

$replicated->schema->storage->debugobj->silence(0);

ok $replicated->schema->storage->pool->has_replicants
    => 'does have replicants';     

is $replicated->schema->storage->pool->num_replicants => 2
    => 'has two replicants';
       
does_ok $replicated_storages[0]
    => 'DBIx::Class::Storage::DBI::Replicated::Replicant';

does_ok $replicated_storages[1]
    => 'DBIx::Class::Storage::DBI::Replicated::Replicant';
    
does_ok $replicated->schema->storage->replicants->{$replicant_names[0]}
    => 'DBIx::Class::Storage::DBI::Replicated::Replicant';

does_ok $replicated->schema->storage->replicants->{$replicant_names[1]}
    => 'DBIx::Class::Storage::DBI::Replicated::Replicant';  

## Add some info to the database

$replicated
    ->schema
    ->populate('Artist', [
        [ qw/artistid name/ ],
        [ 4, "Ozric Tentacles"],
    ]);
                
## Make sure all the slaves have the table definitions

$replicated->replicate;
$replicated->schema->storage->replicants->{$replicant_names[0]}->active(1);
$replicated->schema->storage->replicants->{$replicant_names[1]}->active(1);

## Silence warning about not supporting the is_replicating method if using the
## sqlite dbs.
$replicated->schema->storage->debugobj->silence(1)
  if first { m{^t/} } @replicant_names;
 
$replicated->schema->storage->pool->validate_replicants;

$replicated->schema->storage->debugobj->silence(0);

## Make sure we can read the data.

ok my $artist1 = $replicated->schema->resultset('Artist')->find(4)
    => 'Created Result';

isa_ok $artist1
    => 'DBICTest::Artist';
    
is $artist1->name, 'Ozric Tentacles'
    => 'Found expected name for first result';

## Check that master_read_weight is honored
{
    no warnings 'once';

    # turn off redefined warning
    local $SIG{__WARN__} = sub {};

    local
    *DBIx::Class::Storage::DBI::Replicated::Balancer::Random::_random_number =
	sub { 999 };

    $replicated->schema->storage->balancer->increment_storage;

    is $replicated->schema->storage->balancer->current_replicant,
       $replicated->schema->storage->master
       => 'master_read_weight is honored';

    ## turn it off for the duration of the test
    $replicated->schema->storage->balancer->master_read_weight(0);
    $replicated->schema->storage->balancer->increment_storage;
}

## 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.

$replicated
    ->schema
    ->populate('Artist', [
        [ qw/artistid name/ ],
        [ 5, "Doom's Children"],
        [ 6, "Dead On Arrival"],
        [ 7, "Watergate"],
    ]);

## Make sure all the slaves have the table definitions
$replicated->replicate;

## Should find some data now

ok my $artist2 = $replicated->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 disconnect all the replicants?

is $replicated->schema->storage->pool->connected_replicants => 2
    => "both replicants are connected";
    
$replicated->schema->storage->replicants->{$replicant_names[0]}->disconnect;
$replicated->schema->storage->replicants->{$replicant_names[1]}->disconnect;

is $replicated->schema->storage->pool->connected_replicants => 0
    => "both replicants are now disconnected";

## All these should pass, since the database should automatically reconnect

ok my $artist3 = $replicated->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';

is $replicated->schema->storage->pool->connected_replicants => 1
    => "At Least One replicant reconnected to handle the job";
    
## What happens when we try to select something that doesn't exist?

ok ! $replicated->schema->resultset('Artist')->find(666)
    => 'Correctly failed to find something.';
    
## test the reliable option

TESTRELIABLE: {
	
	$replicated->schema->storage->set_reliable_storage;
	
	ok $replicated->schema->resultset('Artist')->find(2)
	    => 'Read from master 1';
	
	ok $replicated->schema->resultset('Artist')->find(5)
	    => 'Read from master 2';
	    
    $replicated->schema->storage->set_balanced_storage;	    
	    
	ok $replicated->schema->resultset('Artist')->find(3)
        => 'Read from replicant';
}

## Make sure when reliable goes out of scope, we are using replicants again

ok $replicated->schema->resultset('Artist')->find(1)
    => 'back to replicant 1.';
    
ok $replicated->schema->resultset('Artist')->find(2)
    => 'back to replicant 2.';

## set all the replicants to inactive, and make sure the balancer falls back to
## the master.

$replicated->schema->storage->replicants->{$replicant_names[0]}->active(0);
$replicated->schema->storage->replicants->{$replicant_names[1]}->active(0);

{
    ## catch the fallback to master warning
    open my $debugfh, '>', \my $fallback_warning;
    my $oldfh = $replicated->schema->storage->debugfh;
    $replicated->schema->storage->debugfh($debugfh);

    ok $replicated->schema->resultset('Artist')->find(2)
	=> 'Fallback to master';

    like $fallback_warning, qr/falling back to master/
	=> 'emits falling back to master warning';

    $replicated->schema->storage->debugfh($oldfh);
}

$replicated->schema->storage->replicants->{$replicant_names[0]}->active(1);
$replicated->schema->storage->replicants->{$replicant_names[1]}->active(1);

## Silence warning about not supporting the is_replicating method if using the
## sqlite dbs.
$replicated->schema->storage->debugobj->silence(1)
  if first { m{^t/} } @replicant_names;
 
$replicated->schema->storage->pool->validate_replicants;

$replicated->schema->storage->debugobj->silence(0);

ok $replicated->schema->resultset('Artist')->find(2)
    => 'Returned to replicates';
    
## Getting slave status tests

SKIP: {
    ## We skip this tests unless you have a custom replicants, since the default
    ## sqlite based replication tests don't support these functions.
    
    skip 'Cannot Test Replicant Status on Non Replicating Database', 9
     unless DBICTest->has_custom_dsn && $ENV{"DBICTEST_SLAVE0_DSN"};

    $replicated->replicate; ## Give the slaves a chance to catchup.

	ok $replicated->schema->storage->replicants->{$replicant_names[0]}->is_replicating
	    => 'Replicants are replicating';
	    
	is $replicated->schema->storage->replicants->{$replicant_names[0]}->lag_behind_master, 0
	    => 'Replicant is zero seconds behind master';
	    
	## Test the validate replicants
	
	$replicated->schema->storage->pool->validate_replicants;
	
	is $replicated->schema->storage->pool->active_replicants, 2
	    => 'Still have 2 replicants after validation';
	    
	## Force the replicants to fail the validate test by required their lag to
	## be negative (ie ahead of the master!)
	
    $replicated->schema->storage->pool->maximum_lag(-10);
    $replicated->schema->storage->pool->validate_replicants;
    
    is $replicated->schema->storage->pool->active_replicants, 0
        => 'No way a replicant be be ahead of the master';
        
    ## Let's be fair to the replicants again.  Let them lag up to 5
	
    $replicated->schema->storage->pool->maximum_lag(5);
    $replicated->schema->storage->pool->validate_replicants;
    
    is $replicated->schema->storage->pool->active_replicants, 2
        => 'Both replicants in good standing again';	
        
	## Check auto validate
	
	is $replicated->schema->storage->balancer->auto_validate_every, 100
	    => "Got the expected value for auto validate";
	    
		## This will make sure we auto validatge everytime
		$replicated->schema->storage->balancer->auto_validate_every(0);
		
		## set all the replicants to inactive, and make sure the balancer falls back to
		## the master.
		
		$replicated->schema->storage->replicants->{$replicant_names[0]}->active(0);
		$replicated->schema->storage->replicants->{$replicant_names[1]}->active(0);
		
		## Ok, now when we go to run a query, autovalidate SHOULD reconnect
	
	is $replicated->schema->storage->pool->active_replicants => 0
	    => "both replicants turned off";
	    	
	ok $replicated->schema->resultset('Artist')->find(5)
	    => 'replicant reactivated';
	    
	is $replicated->schema->storage->pool->active_replicants => 2
	    => "both replicants reactivated";        
}

## Test the reliably callback

ok my $reliably = sub {
	
    ok $replicated->schema->resultset('Artist')->find(5)
        => 'replicant reactivated';	
	
} => 'created coderef properly';

$replicated->schema->storage->execute_reliably($reliably);

## Try something with an error

ok my $unreliably = sub {
    
    ok $replicated->schema->resultset('ArtistXX')->find(5)
        => 'replicant reactivated'; 
    
} => 'created coderef properly';

throws_ok {$replicated->schema->storage->execute_reliably($unreliably)} 
    qr/Can't find source for ArtistXX/
    => 'Bad coderef throws proper error';
    
## Make sure replication came back

ok $replicated->schema->resultset('Artist')->find(3)
    => 'replicant reactivated';
    
## make sure transactions are set to execute_reliably

ok my $transaction = sub {
	
	my $id = shift @_;
	
	$replicated
	    ->schema
	    ->populate('Artist', [
	        [ qw/artistid name/ ],
	        [ $id, "Children of the Grave"],
	    ]);
	    
    ok my $result = $replicated->schema->resultset('Artist')->find($id)
        => 'Found expected artist';
        
    ok my $more = $replicated->schema->resultset('Artist')->find(1)
        => 'Found expected artist again';
        
   return ($result, $more);
   
} => 'Created a coderef properly';

## Test the transaction with multi return
{
	ok my @return = $replicated->schema->txn_do($transaction, 666)
	    => 'did transaction';
	    
	    is $return[0]->id, 666
	        => 'first returned value is correct';
	        
	    is $return[1]->id, 1
	        => 'second returned value is correct';
}

## Test that asking for single return works
{
	ok my $return = $replicated->schema->txn_do($transaction, 777)
	    => 'did transaction';
	    
	    is $return->id, 777
	        => 'first returned value is correct';
}

## Test transaction returning a single value

{
	ok my $result = $replicated->schema->txn_do(sub {
		ok my $more = $replicated->schema->resultset('Artist')->find(1)
		=> 'found inside a transaction';
		return $more;
	}) => 'successfully processed transaction';
	
	is $result->id, 1
	   => 'Got expected single result from transaction';
}

## Make sure replication came back

ok $replicated->schema->resultset('Artist')->find(1)
    => 'replicant reactivated';
    
## Test Discard changes

{
	ok my $artist = $replicated->schema->resultset('Artist')->find(2)
	    => 'got an artist to test discard changes';
	    
	ok $artist->discard_changes
	   => 'properly discard changes';
}

## Test some edge cases, like trying to do a transaction inside a transaction, etc

{
    ok my $result = $replicated->schema->txn_do(sub {
    	return $replicated->schema->txn_do(sub {
	        ok my $more = $replicated->schema->resultset('Artist')->find(1)
	        => 'found inside a transaction inside a transaction';
	        return $more;    		
    	});
    }) => 'successfully processed transaction';
    
    is $result->id, 1
       => 'Got expected single result from transaction';	  
}

{
    ok my $result = $replicated->schema->txn_do(sub {
    	return $replicated->schema->storage->execute_reliably(sub {
	    	return $replicated->schema->txn_do(sub {
	    		return $replicated->schema->storage->execute_reliably(sub {
			        ok my $more = $replicated->schema->resultset('Artist')->find(1)
			        => 'found inside crazy deep transactions and execute_reliably';
			        return $more; 	    			
	    		});
	    	});    	
    	});
    }) => 'successfully processed transaction';
    
    is $result->id, 1
       => 'Got expected single result from transaction';	  
}     

## Test the force_pool resultset attribute.

{
	ok my $artist_rs = $replicated->schema->resultset('Artist')
        => 'got artist resultset';
	   
	## Turn on Forced Pool Storage
	ok my $reliable_artist_rs = $artist_rs->search(undef, {force_pool=>'master'})
        => 'Created a resultset using force_pool storage';
	   
    ok my $artist = $reliable_artist_rs->find(2) 
        => 'got an artist result via force_pool storage';
}

## Delete the old database files
$replicated->cleanup;

# vim: sw=4 sts=4 :