loncom/loncnew - diff

Return to loncnew CVS log

Up to [LON-CAPA] / loncom

Diff for /loncom/loncnew between versions 1.85 and 1.97

version 1.85, 2007/05/01 01:04:23	version 1.97, 2011/06/16 07:18:53
Line 26	Line 26
# http://www.lon-capa.org/	# http://www.lon-capa.org/
#	#
#	#
# new lonc handles n request out bver m connections to londs.	# new lonc handles n request out over m connections to londs.
# This module is based on the Event class.	# This module is based on the Event class.
# Development iterations:	# Development iterations:
# - Setup basic event loop. (done)	# - Setup basic event loop. (done)
Line 85 my $ClientConnection = 0; # Uniquifier f	Line 85 my $ClientConnection = 0; # Uniquifier f

my $DebugLevel = 0;	my $DebugLevel = 0;
my $NextDebugLevel= 2; # So Sigint can toggle this.	my $NextDebugLevel= 2; # So Sigint can toggle this.
my $IdleTimeout= 600; # Wait 10 minutes before pruning connections.	my $IdleTimeout= 5*60; # Seconds to wait prior to pruning connections.

my $LogTransactions = 0; # When True, all transactions/replies get logged.	my $LogTransactions = 0; # When True, all transactions/replies get logged.
my $executable = $0; # Get the full path to me.	my $executable = $0; # Get the full path to me.
Line 158 sub LogPerm {	Line 158 sub LogPerm {
my $now=time;	my $now=time;
my $local=localtime($now);	my $local=localtime($now);
my $fh=IO::File->new(">>$execdir/logs/lonnet.perm.log");	my $fh=IO::File->new(">>$execdir/logs/lonnet.perm.log");
	chomp($message);
print $fh "$now:$message:$local\n";	print $fh "$now:$message:$local\n";
}	}

Line 348 sub child_exit {	Line 349 sub child_exit {

=head2 Tick	=head2 Tick

Invoked each timer tick.	Invoked each timer tick.

=cut	=cut

Line 440 Trigger disconnections of idle sockets.	Line 441 Trigger disconnections of idle sockets.

sub SetupTimer {	sub SetupTimer {
Debug(6, "SetupTimer");	Debug(6, "SetupTimer");
Event->timer(interval => 1, cb => \&Tick );	Event->timer(interval => 1, cb => \&Tick,
	hard => 1);
}	}

=pod	=pod
Line 486 sub ServerToIdle {	Line 488 sub ServerToIdle {

Event callback for when a client socket is writable.	Event callback for when a client socket is writable.

This callback is established when a transaction reponse is	This callback is established when a transaction response is
avaiable from lond. The response is forwarded to the unix socket	available from lond. The response is forwarded to the unix socket
as it becomes writable in this sub.	as it becomes writable in this sub.

Parameters:	Parameters:
Line 557 sub ClientWritable {	Line 559 sub ClientWritable {
if($errno == POSIX::EWOULDBLOCK \|\|	if($errno == POSIX::EWOULDBLOCK \|\|
$errno == POSIX::EAGAIN \|\|	$errno == POSIX::EAGAIN \|\|
$errno == POSIX::EINTR) {	$errno == POSIX::EINTR) {
# No action taken?	# No action taken...the socket will be writable firing the event again
	# which will result in a retry of the write.
} else { # Unanticipated errno.	} else { # Unanticipated errno.
&Debug(5,"ClientWritable error or peer shutdown".$RemoteHost);	&Debug(5,"ClientWritable error or peer shutdown".$RemoteHost);
$Watcher->cancel; # Stop the watcher.	$Watcher->cancel; # Stop the watcher.
Line 586 Parameters:	Line 589 Parameters:

=item Socket	=item Socket

Socket on which the lond transaction occured. This is a	Socket on which the lond transaction occurred. This is a
LondConnection. The data received is in the TransactionReply member.	LondConnection. The data received are in the TransactionReply member.

=item Transaction	=item Transaction

Line 608 sub CompleteTransaction {	Line 611 sub CompleteTransaction {
StartClientReply($Transaction, $data);	StartClientReply($Transaction, $data);
} else { # Delete deferred transaction file.	} else { # Delete deferred transaction file.
Log("SUCCESS", "A delayed transaction was completed");	Log("SUCCESS", "A delayed transaction was completed");
LogPerm("S:$Transaction->getClient() :".$Transaction->getRequest());	LogPerm("S:".$Transaction->getClient().":".$Transaction->getRequest());
unlink $Transaction->getFile();	unlink($Transaction->getFile());
}	}
}	}

Line 627 sub CompleteTransaction {	Line 630 sub CompleteTransaction {

=item data	=item data

The data to send to apached client.	The data to send to apache client.

=cut	=cut

Line 740 Parameters:	Line 743 Parameters:

=item Restart	=item Restart

nonzero if we are allowed to create a new connection.	non-zero if we are allowed to create a new connection.

=cut	=cut

Line 760 sub KillSocket {	Line 763 sub KillSocket {
delete ($ActiveTransactions{$Socket});	delete ($ActiveTransactions{$Socket});
}	}
if(exists($ActiveConnections{$Socket})) {	if(exists($ActiveConnections{$Socket})) {
	$ActiveConnections{$Socket}->cancel;
delete($ActiveConnections{$Socket});	delete($ActiveConnections{$Socket});
$ConnectionCount--;	$ConnectionCount--;
if ($ConnectionCount < 0) { $ConnectionCount = 0; }	if ($ConnectionCount < 0) { $ConnectionCount = 0; }
Line 771 sub KillSocket {	Line 775 sub KillSocket {
EmptyQueue();	EmptyQueue();
CloseAllLondConnections; # Should all already be closed but...	CloseAllLondConnections; # Should all already be closed but...
}	}
	UpdateStatus();
}	}

=pod	=pod
Line 782 is readable. The action is state depend	Line 787 is readable. The action is state depend

=head3 State=Initialized	=head3 State=Initialized

We''re waiting for the challenge, this is a no-op until the	We're waiting for the challenge, this is a no-op until the
state changes.	state changes.

=head3 State=Challenged	=head3 State=Challenged
Line 792 The connection must echo the challenge b	Line 797 The connection must echo the challenge b

=head3 State=ChallengeReplied	=head3 State=ChallengeReplied

The challenge has been replied to. The we are receiveing the	The challenge has been replied to. Then we are receiving the
'ok' from the partner.	'ok' from the partner.

=head3 State=ReadingVersionString	=head3 State=ReadingVersionString
Line 818 The the key has been requested, now we a	Line 823 The the key has been requested, now we a
=head3 State=Idle	=head3 State=Idle

The encryption key has been negotiated or we have finished	The encryption key has been negotiated or we have finished
reading data from the a transaction. If the callback data has	reading data from the a transaction. If the callback data have
a client as well as the socket iformation, then we are	a client as well as the socket nformation, then we are
doing a transaction and the data received is relayed to the client	doing a transaction and the data received are relayed to the client
before the socket is put on the idle list.	before the socket is put on the idle list.

=head3 State=SendingRequest	=head3 State=SendingRequest
Line 837 to readable to receive the reply.	Line 842 to readable to receive the reply.
The parameter to this function are:	The parameter to this function are:

The event. Implicit in this is the watcher and its data. The data	The event. Implicit in this is the watcher and its data. The data
contains at least the lond connection object and, if a	contain at least the lond connection object and, if a
transaction is in progress, the socket attached to the local client.	transaction is in progress, the socket attached to the local client.

=cut	=cut
Line 942 sub LondReadable {	Line 947 sub LondReadable {
CompleteTransaction($Socket,	CompleteTransaction($Socket,
$ActiveTransactions{$Socket});	$ActiveTransactions{$Socket});
} else {	} else {
Log("SUCCESS", "Connection ".$ConnectionCount." to "	my $count = $Socket->GetClientData();
	Log("SUCCESS", "Connection ".$count." to "
.$RemoteHost." now ready for action");	.$RemoteHost." now ready for action");
}	}
ServerToIdle($Socket); # Next work unit or idle.	ServerToIdle($Socket); # Next work unit or idle.
Line 979 event. The action taken is very state d	Line 985 event. The action taken is very state d
=head3 State = Connected	=head3 State = Connected

The connection is in the process of sending the 'init' hailing to the	The connection is in the process of sending the 'init' hailing to the
lond on the remote end. The connection object''s Writable member is	lond on the remote end. The connection object's Writable member is
called. On error, ConnectionError is called to destroy the connection	called. On error, ConnectionError is called to destroy the connection
and remove it from the ActiveConnections hash	and remove it from the ActiveConnections hash

Line 1190 sub QueueDelayed {	Line 1196 sub QueueDelayed {
=head2 MakeLondConnection	=head2 MakeLondConnection

Create a new lond connection object, and start it towards its initial	Create a new lond connection object, and start it towards its initial
idleness. Once idle, it becomes elligible to receive transactions	idleness. Once idle, it becomes eligible to receive transactions
from the work queue. If the work queue is not empty when the	from the work queue. If the work queue is not empty when the
connection is completed and becomes idle, it will dequeue an entry and	connection is completed and becomes idle, it will dequeue an entry and
start off on it.	start off on it.
Line 1205 sub MakeLondConnection {	Line 1211 sub MakeLondConnection {
&GetServerPort(),	&GetServerPort(),
&GetHostId());	&GetHostId());

if($Connection eq undef) { # Needs to be more robust later.	if($Connection eq undef) {
Log("CRITICAL","Failed to make a connection with lond.");	Log("CRITICAL","Failed to make a connection with lond.");
$ConnectionRetriesLeft--;	$ConnectionRetriesLeft--;
return 0; # Failure.	return 0; # Failure.
Line 1236 sub MakeLondConnection {	Line 1242 sub MakeLondConnection {
&SetupTimer; # Need to handle timeouts with connections...	&SetupTimer; # Need to handle timeouts with connections...
}	}
$ConnectionCount++;	$ConnectionCount++;
	$Connection->SetClientData($ConnectionCount);
Debug(4, "Connection count = ".$ConnectionCount);	Debug(4, "Connection count = ".$ConnectionCount);
if($ConnectionCount == 1) { # First Connection:	if($ConnectionCount == 1) { # First Connection:
QueueDelayed;	QueueDelayed;
}	}
Log("SUCESS", "Created connection ".$ConnectionCount	Log("SUCCESS", "Created connection ".$ConnectionCount
." to host ".GetServerHost());	." to host ".GetServerHost());
return 1; # Return success.	return 1; # Return success.
}	}
Line 1261 reply.	Line 1268 reply.

=item $Client	=item $Client

Connection to the client that is making this request We got the	Connection to the client that is making this request. We got the
request from this socket, and when the request has been relayed to	request from this socket, and when the request has been relayed to
lond and we get a reply back from lond it will get sent to this	lond and we get a reply back from lond it will get sent to this
socket.	socket.
Line 1347 sub QueueTransaction {	Line 1354 sub QueueTransaction {
}	}
}	}

#-------------------------- Lonc UNIX socket handling ---------------------	#-------------------------- Lonc UNIX socket handling -------------------

=pod	=pod

=head2 ClientRequest	=head2 ClientRequest

Callback that is called when data can be read from the UNIX domain	Callback that is called when data can be read from the UNIX domain
socket connecting us with an apache server process.	socket connecting us with an apache server process.

Line 1382 sub ClientRequest {	Line 1389 sub ClientRequest {
$data = $data.$thisread; # Append new data.	$data = $data.$thisread; # Append new data.
$watcher->data($data);	$watcher->data($data);
if($data =~ /\n$/) { # Request entirely read.	if($data =~ /\n$/) { # Request entirely read.
if($data eq "close_connection_exit\n") {	if ($data eq "close_connection_exit\n") {
Log("CRITICAL",	Log("CRITICAL",
"Request Close Connection ... exiting");	"Request Close Connection ... exiting");
CloseAllLondConnections();	CloseAllLondConnections();
exit;	exit;
	} elsif ($data eq "reset_retries\n") {
	Log("INFO", "Resetting Connection Retries.");
	$ConnectionRetriesLeft = $ConnectionRetries;
	&UpdateStatus();
	my $Transaction = LondTransaction->new($data);
	$Transaction->SetClient($socket);
	StartClientReply($Transaction, "ok\n");
	$watcher->cancel();
	return;
}	}
Debug(8, "Complete transaction received: ".$data);	Debug(8, "Complete transaction received: ".$data);
if($LogTransactions) {	if ($LogTransactions) {
Log("SUCCESS", "Transaction: '$data'"); # Transaction has \n.	Log("SUCCESS", "Transaction: '$data'"); # Transaction has \n.
}	}
my $Transaction = LondTransaction->new($data);	my $Transaction = LondTransaction->new($data);
Line 1442 sub accept_client {	Line 1458 sub accept_client {
Callback that is called when a connection is received on the unix	Callback that is called when a connection is received on the unix
socket for a new client of lonc. The callback is parameterized by the	socket for a new client of lonc. The callback is parameterized by the
event.. which is a-priori assumed to be an io event, and therefore has	event.. which is a-priori assumed to be an io event, and therefore has
an fd member that is the Listener socket. We Accept the connection	an fd member that is the Listener socket. We accept the connection
and register a new event on the readability of that socket:	and register a new event on the readability of that socket:

=cut	=cut
Line 1522 sub GetServerPort {	Line 1538 sub GetServerPort {
Setup a lonc listener event. The event is called when the socket	Setup a lonc listener event. The event is called when the socket
becomes readable.. that corresponds to the receipt of a new	becomes readable.. that corresponds to the receipt of a new
connection. The event handler established will accept the connection	connection. The event handler established will accept the connection
(creating a communcations channel), that int turn will establish	(creating a communcations channel), that in turn will establish
another event handler to subess requests.	another event handler to subess requests.

=head2 Parameters:	=head2 Parameters:
Line 1662 sub ToggleDebug {	Line 1678 sub ToggleDebug {

This sub implements a child process for a single lonc daemon.	This sub implements a child process for a single lonc daemon.
Optional parameter:	Optional parameter:
$socket - if provided, this is a socket already open for listen	$socket - if provided, this is a socket already open for listening
on the client socket. Otherwise, a new listen is set up.	on the client socket. Otherwise, a new listener is set up.

=cut	=cut

Line 1720 sub ChildProcess {	Line 1736 sub ChildProcess {
cb => \&ToggleDebug,	cb => \&ToggleDebug,
data => "INT");	data => "INT");

	# Block the pipe signal we'll get when the socket disconnects. We detect
	# socket disconnection via send/receive failures. On disconnect, the
	# socket becomes readable .. which will force the disconnect detection.

	my $set = POSIX::SigSet->new(SIGPIPE);
	sigprocmask(SIG_BLOCK, $set);

# Figure out if we got passed a socket or need to open one to listen for	# Figure out if we got passed a socket or need to open one to listen for
# client requests.	# client requests.

Line 1763 sub CreateChild {	Line 1786 sub CreateChild {
my $sigset = POSIX::SigSet->new(SIGINT);	my $sigset = POSIX::SigSet->new(SIGINT);
sigprocmask(SIG_BLOCK, $sigset);	sigprocmask(SIG_BLOCK, $sigset);
$RemoteHost = $host;	$RemoteHost = $host;
	ShowStatus('Parent keeping the flock'); # Update time in status message.
Log("CRITICAL", "Forking server for ".$host);	Log("CRITICAL", "Forking server for ".$host);
my $pid = fork;	my $pid = fork;
if($pid) { # Parent	if($pid) { # Parent
Line 1897 sub parent_listen {	Line 1921 sub parent_listen {

sub parent_clean_up {	sub parent_clean_up {
my ($loncapa_host) = @_;	my ($loncapa_host) = @_;
Debug(-1, "parent_clean_up: $loncapa_host");	Debug(1, "parent_clean_up: $loncapa_host");

my $socket_file = &GetLoncSocketPath($loncapa_host);	my $socket_file = &GetLoncSocketPath($loncapa_host);
unlink($socket_file); # No problem if it doesn't exist yet [startup e.g.]	unlink($socket_file); # No problem if it doesn't exist yet [startup e.g.]
Line 2055 die "Main Event loop exited: $ret";	Line 2079 die "Main Event loop exited: $ret";
=head1 CheckKids	=head1 CheckKids

Since kids do not die as easily in this implementation	Since kids do not die as easily in this implementation
as the previous one, there is no need to restart the	as the previous one, there is no need to restart the
dead ones (all dead kids get restarted when they die!!)	dead ones (all dead kids get restarted when they die!!)
The only thing this function does is to pass USR1 to the	The only thing this function does is to pass USR1 to the
kids so that they report their status.	kids so that they report their status.
Line 2125 sub UpdateKids {	Line 2149 sub UpdateKids {
=head1 Restart	=head1 Restart

Signal handler for HUP... all children are killed and	Signal handler for HUP... all children are killed and
we self restart. This is an el-cheapo way to re read	we self restart. This is an el-cheapo way to re-read
the config file.	the config file.

=cut	=cut
Line 2255 A hash of lond connections that have no	Line 2279 A hash of lond connections that have no
can be closed if they are idle for a long enough time.	can be closed if they are idle for a long enough time.

=cut	=cut

	=pod

	=head1 Log messages

	The following is a list of log messages that can appear in the
	lonc.log file. Each log file has a severity and a message.

	=over 2

	=item Warning A socket timeout was detected

	If there are pending transactions in the socket's queue,
	they are failed (saved if critical). If the connection
	retry count gets exceeded by this, the
	remote host is marked as dead.
	Called when timeouts occurred during the connection and
	connection dialog with a remote host.

	=item Critical Host makred DEAD <hostname>

	The numer of retry counts for contacting a host was
	exceeded. The host is marked dead an no
	further attempts will be made by that child.

	=item Info lonc pipe client hung up on us

	Write to the client pipe indicated no data transferred
	Socket to remote host is shut down. Reply to the client
	is discarded. Note: This is commented out in &ClientWriteable

	=item Success Reply from lond: <data>

	Can be enabled for debugging by setting LogTransactions to nonzero.
	Indicates a successful transaction with lond, <data> is the data received
	from the remote lond.

	=item Success A delayed transaction was completed

	A transaction that must be reliable was executed and completed
	as lonc restarted. This is followed by a mesage of the form

	S: client-name : request

	=item WARNING Failing transaction <cmd>:<subcmd>

	Transaction failed on a socket, but the failure retry count for the remote
	node has not yet been exhausted (the node is not yet marked dead).
	cmd is the command, subcmd is the subcommand. This results from a con_lost
	when communicating with lond.

	=item WARNING Shutting down a socket

	Called when a socket is being closed to lond. This is emitted both when
	idle pruning is being done and when the socket has been disconnected by the remote.

	=item WARNING Lond connection lost.

	Called when a read from lond's socket failed indicating lond has closed the
	connection or died. This should be followed by one or more

	"WARNING Failing transaction..." msgs for each in-flight or queued transaction.

	=item INFO Connected to lond version: <version>

	When connection negotiation is complete, the lond version is requested and logged here.

	=item SUCCESS Connection n to host now ready for action

	Emitted when connection has been completed with lond. n is then number of
	concurrent connections and host, the host to which the connection has just
	been established.

	=item WARNING Connection to host has been disconnected

	Write to a lond resulted in failure status. Connection to lond is dropped.

	=item SUCCESS Created connection n to host host

	Initial connection request to host..(before negotiation).

	=item CRITICAL Request Close Connection ... exiting

	Client has sent "close_connection_exit" The loncnew server is exiting.

	=item INFO Resetting Connection Retries

	Client has sent "reset_retries" The lond connection retries are reset to zero for the
	corresponding lond.

	=item SUCCESS Transaction <data>

	Only emitted if the global variable $LogTransactions was set to true.
	A client has requested a lond transaction <data> is the contents of the request.

	=item SUCCESS Toggled transaction logging <LogTransactions>

	The state of the $LogTransactions global has been toggled, and its current value
	(after being toggled) is displayed. When non zero additional logging of transactions
	is enabled for debugging purposes. Transaction logging is toggled on receipt of a USR2
	signal.

	=item CRITICAL Abnormal exit. Child <pid> for <host> died thorugh signal.

	QUIT signal received. lonc child process is exiting.

	=item SUCCESS New debugging level for <RemoteHost> now <DebugLevel>

	Debugging toggled for the host loncnew is talking with.
	Currently debugging is a level based scheme with higher number
	conveying more information. The daemon starts out at
	DebugLevel 0 and can toggle back and forth between that and
	DebugLevel 2 These are controlled by
	the global variables $DebugLevel and $NextDebugLevel
	The debug level can go up to 9.
	SIGINT toggles the debug level. The higher the debug level the
	more debugging information is spewed. See the Debug
	sub in loncnew.

	=item CRITICAL Forking server for host

	A child is being created to service requests for the specified host.


	=item WARNING Request for a second child on hostname

	Somehow loncnew was asked to start a second child on a host that already had a child
	servicing it. This request is not honored, but themessage is emitted. This could happen
	due to a race condition. When a client attempts to contact loncnew for a new host, a child
	is forked off to handle the requests for that server. The parent then backs off the Unix
	domain socket leaving it for the child to service all requests. If in the time between
	creating the child, and backing off, a new connection request comes in to the unix domain
	socket, this could trigger (unlikely but remotely possible),.

	=item CRITICAL ------ Starting Children ----

	This message should probably be changed to "Entering event loop" as the loncnew only starts
	children as needed. This message is emitted as new events are established and
	the event processing loop is entered.

	=item INFO Updating connections via SIGUSR2

	SIGUSR2 received. The original code would kill all clients, re-read the host file,
	then restart children for each host. Now that children are started on demand, this
	just kills all child processes and lets requests start them as needed again.


	=item CRITICAL Restarting

	SigHUP received. all the children are killed and the script exec's itself to start again.

	=item CRITICAL Nicely killing lonc for host pid = <pid>

	Attempting to kill the child that is serving the specified host (pid given) cleanly via
	SIGQUIT. The child should handle that, clean up nicely and exit.

	=item CRITICAL Nastily killing lonc for host pid = <pid>

	The child specified did not die when requested via SIGQUIT. Therefore it is killed
	via SIGKILL.

	=item CRITICAL Asked to kill children.. first be nice..

	In the parent's INT handler. INT kills the child processes. This inidicate loncnew
	is about to attempt to kill all known children via SIGQUIT. This message should be followed
	by one "Nicely killing" message for each extant child.

	=item CRITICAL Now kill children nasty

	In the parent's INT handler. remaining children are about to be killed via
	SIGKILL. Should be followed by a Nastily killing... for each lonc child that
	refused to die.

	=item CRITICAL Master process exiting

	In the parent's INT handler. just prior to the exit 0 call.

	=back

	=cut

FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>

Removed from v.1.85
changed lines
	Added in v.1.97