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mirror of https://github.com/pgbackrest/pgbackrest.git synced 2024-12-14 10:13:05 +02:00
pgbackrest/lib/pgBackRest/Protocol/CommonMaster.pm
David Steele d0b6f78b20 More flexible configuration for databases
Master and standby can both be configured on the backup server and pgBackRest will automatically determine which is the master. This means no configuration changes for backup are required after failing over from a master to standby when a separate backup server is used.
2016-08-24 12:39:27 -04:00

411 lines
13 KiB
Perl

####################################################################################################################################
# PROTOCOL COMMON MASTER MODULE
####################################################################################################################################
package pgBackRest::Protocol::CommonMaster;
use parent 'pgBackRest::Protocol::Common';
use strict;
use warnings FATAL => qw(all);
use Carp qw(confess);
use File::Basename qw(dirname);
use Time::HiRes qw(gettimeofday);
use Scalar::Util qw(blessed);
use lib dirname($0) . '/../lib';
use pgBackRest::Common::Exception;
use pgBackRest::Common::Ini;
use pgBackRest::Common::Log;
use pgBackRest::Protocol::Common;
use pgBackRest::Protocol::IO;
####################################################################################################################################
# CONSTRUCTOR
####################################################################################################################################
sub new
{
my $class = shift; # Class name
# Assign function parameters, defaults, and log debug info
my
(
$strOperation,
$strRemoteType, # Type of remote (DB or BACKUP)
$strName, # Name of the protocol
$strId, # Id of this process for error messages
$strCommand, # Command to execute on local/remote
$iBufferMax, # Maximum buffer size
$iCompressLevel, # Set compression level
$iCompressLevelNetwork, # Set compression level for network only compression
$iProtocolTimeout # Protocol timeout
) =
logDebugParam
(
__PACKAGE__ . '->new', \@_,
{name => 'strRemoteType'},
{name => 'strName'},
{name => 'strId'},
{name => 'strCommand'},
{name => 'iBufferMax'},
{name => 'iCompressLevel'},
{name => 'iCompressLevelNetwork'},
{name => 'iProtocolTimeout'}
);
# Create the class hash
my $self = $class->SUPER::new($iBufferMax, $iCompressLevel, $iCompressLevelNetwork, $iProtocolTimeout, $strName);
bless $self, $class;
# Set remote to specificied value
$self->{strRemoteType} = $strRemoteType;
# Set command
if (!defined($strCommand))
{
confess &log(ASSERT, 'strCommand must be set');
}
# Execute the command
$self->{io} = pgBackRest::Protocol::IO->new3($strId, $strCommand, $iProtocolTimeout, $iBufferMax);
# Check greeting to be sure the protocol matches
$self->greetingRead();
# Setup the keepalive timer
$self->{fKeepAliveTimeout} = $iProtocolTimeout / 2 > 120 ? 120 : $iProtocolTimeout / 2;
$self->{fKeepAliveTime} = gettimeofday();
# Set the id to be used for messages (especially error messages)
$self->{strId} = $strId;
# Set the error prefix used when raising error messages
$self->{strErrorPrefix} = 'raised on ' . $self->{strId} . ' host';
# Return from function and log return values if any
return logDebugReturn
(
$strOperation,
{name => 'self', value => $self}
);
}
####################################################################################################################################
# close
####################################################################################################################################
sub close
{
my $self = shift;
# Assign function parameters, defaults, and log debug info
my ($strOperation) = logDebugParam(__PACKAGE__ . '->close');
# Exit status defaults to success
my $iExitStatus = 0;
my $bClosed = false;
# Only send the exit command if the process is running
if (defined($self->{io}) && defined($self->{io}->pIdGet()))
{
&log(TRACE, "sending exit command to process");
eval
{
$self->cmdWrite('exit');
};
if ($@)
{
my $oMessage = $@;
my $strError = 'unable to shutdown protocol';
my $strHint = 'HINT: the process completed successfully but protocol-timeout may need to be increased.';
if (blessed($oMessage) && $oMessage->isa('pgBackRest::Common::Exception'))
{
$iExitStatus = $oMessage->code();
}
else
{
if (!defined($oMessage))
{
$oMessage = 'unknown error';
}
$iExitStatus = ERROR_UNKNOWN;
}
&log(WARN,
$strError . ($iExitStatus == ERROR_UNKNOWN ? '' : ' [' . $oMessage->code() . ']') . ': ' .
($iExitStatus == ERROR_UNKNOWN ? $oMessage : $oMessage->message()) . "\n${strHint}");
}
undef($self->{io});
$bClosed = true;
}
# Return from function and log return values if any
return logDebugReturn
(
$strOperation,
{name => 'iExitStatus', value => $iExitStatus, trace => !$bClosed}
);
}
####################################################################################################################################
# DESTROY
####################################################################################################################################
sub DESTROY
{
my $self = shift;
$self->close();
}
####################################################################################################################################
# greetingRead
#
# Read the greeting and make sure it is as expected.
####################################################################################################################################
sub greetingRead
{
my $self = shift;
# Get the first line of output from the remote if possible
my $strLine = $self->{io}->lineRead(undef, undef, undef, true);
# If the line could not be read or does equal the greeting then error and exit
if (!defined($strLine) || $strLine ne $self->{strGreeting})
{
$self->{io}->kill();
confess &log(ERROR, 'protocol version mismatch' . (defined($strLine) ? ": ${strLine}" : ''), ERROR_HOST_CONNECT);
}
$self->outputRead();
}
####################################################################################################################################
# outputRead
#
# Read output from the remote process.
####################################################################################################################################
sub outputRead
{
my $self = shift;
# Assign function parameters, defaults, and log debug info
my
(
$strOperation,
$bOutputRequired,
$bSuppressLog,
$bWarnOnError,
) =
logDebugParam
(
__PACKAGE__ . '->outputRead', \@_,
{name => 'bOutputRequired', default => false, trace => true},
{name => 'bSuppressLog', required => false, trace => true},
{name => 'bWarnOnError', default => false, trace => true},
);
my $strLine;
my $strOutput;
my $bError = false;
my $iErrorCode;
my $strError;
# Read output lines
while ($strLine = $self->{io}->lineRead())
{
# Exit if an error is found
if ($strLine =~ /^ERROR.*/)
{
$bError = true;
$iErrorCode = (split(' ', $strLine))[1];
last;
}
# Exit if OK is found
if ($strLine =~ /^OK$/)
{
last;
}
# Else append to output
$strOutput .= (defined($strOutput) ? "\n" : '') . substr($strLine, 1);
}
# Raise any errors
if ($bError)
{
my $strError = $self->{strErrorPrefix} . (defined($strOutput) ? ": ${strOutput}" : '');
# Raise the error if a warning is not requested
if (!$bWarnOnError)
{
confess &log(ERROR, $strError, $iErrorCode, $bSuppressLog);
}
&log(WARN, $strError, $iErrorCode);
undef($strOutput);
}
# Reset the keep alive time
$self->{fKeepAliveTime} = gettimeofday();
# If output is required and there is no output, raise exception
if ($bOutputRequired && !defined($strOutput))
{
$self->{io}->waitPid();
confess &log(ERROR, "$self->{strErrorPrefix}: output is not defined", ERROR_PROTOCOL_OUTPUT_REQUIRED);
}
# Return from function and log return values if any
return logDebugReturn
(
$strOperation,
{name => 'strOutput', value => $strOutput, trace => true}
);
}
####################################################################################################################################
# commandParamString
#
# Output command parameters in the hash as a string (used for debugging).
####################################################################################################################################
sub commandParamString
{
my $self = shift;
my $oParamHashRef = shift;
my $strParamList = '';
if (defined($oParamHashRef))
{
foreach my $strParam (sort(keys(%$oParamHashRef)))
{
$strParamList .= (defined($strParamList) ? ',' : '') . "${strParam}=" .
(defined(${$oParamHashRef}{"${strParam}"}) ? ${$oParamHashRef}{"${strParam}"} : '[undef]');
}
}
return $strParamList;
}
####################################################################################################################################
# cmdWrite
#
# Send command to remote process.
####################################################################################################################################
sub cmdWrite
{
my $self = shift;
# Assign function parameters, defaults, and log debug info
my
(
$strOperation,
$strCommand,
$oParamRef,
) =
logDebugParam
(
__PACKAGE__ . '->cmdWrite', \@_,
{name => 'strCommand', trace => true},
{name => 'oParamRef', required => false, trace => true}
);
if (defined($oParamRef))
{
$strCommand .= ":\n";
foreach my $strParam (sort(keys(%$oParamRef)))
{
if ($strParam =~ /=/)
{
confess &log(ASSERT, "param \"${strParam}\" cannot contain = character");
}
my $strValue = ${$oParamRef}{"${strParam}"};
if ($strParam =~ /\n\$/)
{
confess &log(ASSERT, "param \"${strParam}\" value cannot end with LF");
}
if (defined(${strValue}))
{
$strCommand .= "${strParam}=${strValue}\n";
}
}
$strCommand .= 'end';
}
logDebugMisc
(
$strOperation, undef,
{name => 'strCommand', value => $strCommand, trace => true}
);
# Write out the command
$self->{io}->lineWrite($strCommand);
# Reset the keep alive time
$self->{fKeepAliveTime} = gettimeofday();
# Return from function and log return values if any
logDebugReturn($strOperation);
}
####################################################################################################################################
# cmdExecute
#
# Send command to remote process and wait for output.
####################################################################################################################################
sub cmdExecute
{
my $self = shift;
my $strCommand = shift;
my $oParamRef = shift;
my $bOutputRequired = shift;
my $bWarnOnError = shift;
$self->cmdWrite($strCommand, $oParamRef);
return $self->outputRead($bOutputRequired, undef, $bWarnOnError);
}
####################################################################################################################################
# keepAlive
#
# Send periodic noops so the remote does not time out.
####################################################################################################################################
sub keepAlive
{
my $self = shift;
if (gettimeofday() - $self->{fKeepAliveTimeout} > $self->{fKeepAliveTime})
{
$self->noOp();
$self->{fKeepAliveTime} = gettimeofday();
# Keep alive test point
&log(TEST, TEST_KEEP_ALIVE);
}
}
####################################################################################################################################
# noOp
#
# Send noop to test connection or keep it alive.
####################################################################################################################################
sub noOp
{
my $self = shift;
$self->cmdExecute(OP_NOOP, undef, false);
}
1;