NAME¶
File::RsyncP - Perl Rsync client
SYNOPSIS¶
use File::RsyncP;
my $rs = File::RsyncP->new({
logLevel => 1,
rsyncCmd => "/bin/rsync",
rsyncArgs => [
"--numeric-ids",
"--perms",
"--owner",
"--group",
"--devices",
"--links",
"--ignore-times",
"--block-size=700",
"--relative",
"--recursive",
"-v",
],
});
#
# Receive files from remote srcDirectory to local destDirectory
# by running rsyncCmd with rsyncArgs.
#
$rs->remoteStart(1, srcDirectory);
$rs->go(destDirectory);
$rs->serverClose;
#
# Send files to remote destDirectory from local srcDirectory
# by running rsyncCmd with rsyncArgs.
#
$rs->remoteStart(0, destDirectory);
$rs->go(srcDirectory);
$rs->serverClose;
#
# Receive files from a remote module to local destDirectory by
# connecting to an rsyncd server. ($module is the name from
# /etc/rsyncd.conf.)
#
my $port = 873;
$rs->serverConnect($host, $port);
$rs->serverService($module, $authUser, $authPasswd, 0);
$rs->serverStart(1, ".");
$rs->go(destDirectory);
$rs->serverClose;
#
# Get finals stats. This is a hashref containing elements
# totalRead, totalWritten, totalSize, plus whatever the FileIO
# module might add.
#
my $stats = $rs->statsFinal;
DESCRIPTION¶
File::RsyncP is a perl implementation of an Rsync client. It is compatible with
Rsync 2.5.5 - 2.6.3 (protocol versions 26-28). It can send or receive files,
either by running rsync on the remote machine, or connecting to an rsyncd
deamon on the remote machine.
What use is File::RsyncP? The main purpose is that File::RsyncP separates all
file system I/O into a separate module, which can be replaced by any module of
your own design. This allows rsync interfaces to non-filesystem data types
(eg: databases) to be developed with relative ease.
File::RsyncP was initially written to provide an Rsync interface for BackupPC,
<
http://backuppc.sourceforge.net>. See BackupPC for programming
examples.
File::RsyncP does not yet provide a command-line interface that mimics native
Rsync. Instead it provides an API that makes it possible to write simple
scripts that talk to rsync or rsyncd.
The File::RsyncP::FileIO module contains the default file system access
functions. File::RsyncP::FileIO may be subclassed or replaced by a custom
module to provide access to non-filesystem data types.
Getting Started¶
First some background. When you run rsync is parses its command-line arguments,
then it either connects to a remote rsyncd daemon, or runs an rsync on the
remote machine via ssh or rsh. At this point there are two rsync processes:
the one you invoked and the one on the remote machine. The one on the local
machine is called the client, and the one on the remote machine is the server.
One side (either the client or server) will send files and the other will
receive files. The sending rsync generates a file list and sends it to the
receiving side. The receiving rsync will fork a child process.
File::RsyncP does not (yet) have a command-line script that mimics rsync's
startup processing. Think of File::RsyncP as one level below the command-line
rsync. File::RsyncP implements the client side of the connection, and
File::RsyncP knows how to run the remote side (eg, via rsh or ssh) or to
connect to a remote rsyncd daemon. File::RsyncP automatically adds the
internal --server and --sender options (if necessary) to the options passed to
the remote rsync.
To initiate any rsync session the File::RsyncP->new function should be
called. It takes a hashref of parameters:
- logLevel
- An integer level of verbosity. Zero means be quiet, 1 will give some
general information, 2 will some output per file, higher values give more
output. 10 will include byte dumps of all data read/written, which will
make the log output huge.
- rsyncCmd
- The command to run the remote peer of rsync. By default the rsyncArgs are
appended to the rsyncCmd to create the complete command before it is run.
This behavior is affected by rsyncCmdType.
rsyncCmd can either be a single string giving the path of the rsync command
to run (eg: /bin/rsync) or a list containing the command and arguments,
eg:
rsyncCmd => [qw(
/bin/ssh -l user host /bin/rsync
)],
or:
rsyncCmd => ["/bin/ssh", "-l", $user, $host, "/bin/rsync"],
Also, rsyncCmd can also be set to a code reference (ie: a perl sub). In this
case the code is called without arguments or other processing. It is up to
the perl code you supply to exec() the remote rsync.
This option is ignored if you are connecting to an rsyncd daemon.
- rsyncCmdType
- By default the complete remote rsync command is created by taking rsyncCmd
and appending rsyncArgs. This beavhior can be modified by specifying
certain values for rsyncCmdType:
- 'full'
- rsyncCmd is taken to be the complete command, including all rsync
arguments. It is the caller's responsibility to build the correct remote
rsync command, togheter will all the rsync arguments. You still need to
specify rsyncArgs, so the local File::RsyncP knows how to behave.
- 'shell'
- rsyncArgs are shell escaped before appending to rsyncCmd.
This option is ignored if you are connecting to an rsyncd daemon.
- rsyncArgs
- A list of rsync arguments. The full remote rsync command that is run will
be rsyncCmd appended with --server (and optionally --sender if the remote
is a sender) and finally all of rsyncArgs.
- protocol_version
- What we advertize our protocol version to be. Default is 28.
- logHandler
- A subroutine reference to a function that handles all the log messages.
The default is a subroutine that prints the messages to STDERR.
- pidHandler
- An optional subroutine reference to a function that expects two integers:
the pid of the rsync process (ie: the pid on the local machine that is
likely ssh) and the child pid when we are receiving files. If defined,
this function is called once when the rsync process is forked, and again
when the child is forked during receive.
- fio
- The file IO object that will handle all the file system IO. The default is
File::RsyncP::FileIO->new.
This can be replaced with a new module of your choice, or you can subclass
File::RsyncP::FileIO.
- timeout
- Timeout in seconds for IO. Default is 0, meaning no timeout. Uses
alarm() and it is the caller's responsbility to catch the alarm
signal.
- doPartial
- If set, a partial rsync is done. This is to support resuming full backups
in BackupPC. When doPartial is set, the --ignore-times option can be set
on a per-file basis. On each file in the file list,
File::RsyncP::FileIO-> ignoreAttrOnFile() is called on each
file, and this returns whether or not attributes should be ignored on that
file. If ignoreAttrOnFile() returns 1 then it's as though
--ignore-times was set for that file.
An example of calling File::RsyncP->new is:
my $rs = File::RsyncP->new({
logLevel => 1,
rsyncCmd => ["/bin/rsh", $host, "-l", $user, "/bin/rsync"],
rsyncArgs => [
"--numeric-ids",
"--perms",
"--owner",
"--group",
"--devices",
"--links",
"--ignore-times",
"--block-size=700",
"--relative",
"--recursive",
"-v",
],
});
A fuller example showing most of the parameters and
qw() for the
rsyncArgs is:
my $rs = File::RsyncP->new({
logLevel => 1,
rsyncCmd => ["/bin/rsh", $host, "-l", $user, "/bin/rsync"],
rsyncArgs => [qw(
--numeric-ids
--perms
--owner
--group
--devices
--links
--ignore-times
--block-size=700
--relative
--recursive
-v
)],
logHandler => sub {
my($str) = @_;
print MyHandler "log: $str\n";
};
fio => File::RsyncP::FileIO->new({
logLevel => 1,
});
});
Talking to a remote Rsync¶
File::RsyncP can talk to a remote rsync using this sequence of functions:
- remoteStart(remoteSend, remoteDir)
- Starts the remote server by executing the command specified in the
rsyncCmd parameter to File::RsyncP->new, together with the rsyncArgs.
If the client is receiving files from the server then remoteSend should be
non-zero and remoteDir is the source directory on the remote machine. If
the client is sending files to the remote server then remoteSend should be
zero and remoteDir is the destination directory on the remote machine.
Returns undef on success and non-zero on error.
- go(localDir)
- Run the client rsync. localDir is the source directory on the local
machine if the client is sending files, or it is the destination directory
on the local machine if the client is receiving files. Returns undef on
success.
- serverClose()
- Call this after go() to finish up. Returns undef on success.
- statsFinal()
- This can be optionally called to pickup the transfer stats. It returns a
hashref containing elements totalRead, totalWritten, totalSize, plus
whatever the FileIO module might add.
- abort()
- Call this function to abort the transfer.
An example of sending files to a remote rsync is:
#
# Send files to remote destDirectory from local srcDirectory
# by running rsyncCmd with rsyncArgs.
#
$rs->remoteStart(0, destDirectory);
$rs->go(srcDirectory);
$rs->serverClose;
An example of receiving files from a remote rsync is:
#
# Receive files from remote srcDirectory to local destDirectory
# by running rsyncCmd with rsyncArgs.
#
$rs->remoteStart(1, srcDirectory);
$rs->go(destDirectory);
$rs->serverClose;
Talking to a remote Rsync daemon¶
File::RsyncP can connect to a remote Rsync daemon using this sequence of
functions:
- serverConnect(host, port)
- Connect to the Rsync daemon on the given string host and integer port. The
port argument is optional and it defaults to 873. On error serverConnect
returns a string error message. On success it returns undef.
- serverService(module, authUser, authPasswd, authRequired)
- Specify which module to use (a "module" is the symbolic name
that appears inside "[...]" /etc/rsyncd.conf), the user's
credentials (authUser and authPasswd) and whether authorization is
mandatory (authRequired). If set to a non-zero value, authRequired ensures
that the remote Rsync daemon requires authentication. If necessary, this
is to ensure that you don't connect to an insecure Rsync daemon. The auth
arguments are optional if the selected rsyncd module doesn't require
authentication.
See the rsyncd.conf manual page for more information. For example, if a host
called navajo had a /etc/rsyncd.conf contains these lines:
[test]
path = /data/test
comment = test module
auth users = craig, celia
secrets file = /etc/rsyncd.secrets
and /etc/rsyncd.secrets contained:
craig:xxx
then you could connect to this rsyncd using:
$rs->serverConnect("navajo", 873);
$rs->serverService("test", "craig", "xxx", 0);
The value of the authRequired argument doesn't matter in this case.
On error serverService returns a string error message. On success it returns
undef.
- serverStart(remoteSend, remoteDir)
- Starts the remote server. If the client is receiving files from the server
then remoteSend should be non-zero. If the client is sending files to the
remote server then remoteSend should be zero. The remoteDir typically
starts with the module name, followed by any directory below the module.
Or remoteDir can be just "." to refer to the top-level module
directory. Returns undef on success.
- go(localDir)
- Run the client rsync. localDir is the source directory on the local
machine if the client is sending files, or it is the destination directory
on the local machine if the client is receiving files. Returns undef on
success.
- serverClose()
- Call this after go() to finish up. Returns undef on success.
- abort()
- Call this function to abort the transfer.
An example of sending files to a remote rsyncd daemon is:
#
# Send files to a remote module from a local srcDirectory by
# connecting to an rsyncd server. ($module is the name from
# /etc/rsyncd.conf.)
#
my $port = 873;
$rs->serverConnect($host, $port);
$rs->serverService($module, $authUser, $authPasswd);
$rs->serverStart(0, ".");
$rs->go(srcDirectory);
$rs->serverClose;
An example of receiving files from a remote rsyncd daemon is:
#
# Receive files from a remote module to local destDirectory by
# connecting to an rsyncd server. ($module is the name from
# /etc/rsyncd.conf.)
#
my $port = 873;
$rs->serverConnect($host, $port);
$rs->serverService($module, $authUser, $authPasswd);
$rs->serverStart(1, ".");
$rs->go(destDirectory);
$rs->serverClose;
LIMITATIONS¶
The initial version of File::RsyncP (0.10) has a number of limitations:
- •
- File::RsyncP only implements a modest subset of Rsync options and
features. In particular, as of 0.10 only these options are supported:
--numeric-ids
--perms|-p
--owner|-o
--group|-g
--devices|D
--links|-l
--ignore-times|I
--block-size=i
--verbose|-v
--recursive|-r
--relative|-R
Hardlinks are currently not supported. Other options that only affect the
remote side will work correctly since they are passed to the remote Rsync
unchanged.
- •
- Also, --relative semantics are not implemented to match rsync, and the
trailing "/" behavior of rsync (meaning directory contents, not
the directory itself) are not implemented in File::RsyncP.
- •
- File::RsyncP does not yet provide a command-line interface that mimics
native Rsync.
- •
- File::RsyncP might work with slightly earlier versions of Rsync but has
not been tested. It certainly will not work with antique versions of
Rsync.
- •
- File::RsyncP does not compute file deltas (ie: it behaves as though
--whole-file is specified) or implement exclude or include options when
sending files. File::RsyncP does handle file deltas and exclude and
include options when receiving files.
- •
- File::RsyncP does not yet implement server functionality (acting like the
remote end of a connection or a daemon). Since the protocol is relatively
symmetric this is not difficult to add, so it should appear in a future
version.
AUTHOR¶
File::RsyncP::FileList was written by Craig Barratt
<cbarratt@users.sourceforge.net> based on rsync 2.5.5.
Rsync was written by Andrew Tridgell <tridge@samba.org> and Paul
Mackerras. It is available under a GPL license. See
http://rsync.samba.org.
LICENSE¶
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License in the LICENSE
file along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
SEE ALSO¶
See <
http://perlrsync.sourceforge.net> for File::RsyncP's SourceForge home
page.
See File::RsyncP::FileIO, File::RsyncP::Digest, and File::RsyncP::FileList.
Also see BackupPC's lib/BackupPC/Xfer/Rsync.pm for other examples.