# $Id: IRSpy.pm,v 1.84 2007-04-30 11:28:37 mike Exp $
package ZOOM::IRSpy;
use 5.008;
use strict;
use warnings;
use Data::Dumper; # For debugging only
use File::Basename;
use XML::LibXSLT;
use XML::LibXML;
use XML::LibXML::XPathContext;
use ZOOM;
use Net::Z3950::ZOOM 1.13; # For the ZOOM version-check only
use ZOOM::IRSpy::Node;
use ZOOM::IRSpy::Connection;
use ZOOM::IRSpy::Stats;
use ZOOM::IRSpy::Utils qw(cql_target render_record
irspy_xpath_context irspy_make_identifier
irspy_record2identifier);
our @ISA = qw();
our $VERSION = '0.02';
our $irspy_to_zeerex_xsl = dirname(__FILE__) . '/../../xsl/irspy2zeerex.xsl';
# Enumeration for callback functions to return
package ZOOM::IRSpy::Status;
sub OK { 29 } # No problems, task is still progressing
sub TASK_DONE { 18 } # Task is complete, next task should begin
sub TEST_GOOD { 8 } # Whole test is complete, and succeeded
sub TEST_BAD { 31 } # Whole test is complete, and failed
sub TEST_SKIPPED { 12 } # Test couldn't be run
package ZOOM::IRSpy;
=head1 NAME
ZOOM::IRSpy - Perl extension for discovering and analysing IR services
=head1 SYNOPSIS
use ZOOM::IRSpy;
$spy = new ZOOM::IRSpy("target/string/for/irspy/database");
$spy->targets(@targets);
$spy->initialise("Main");
$res = $spy->check();
=head1 DESCRIPTION
This module exists to implement the IRspy program, which discovers,
analyses and monitors IR servers implementing the Z39.50 and SRU/W
protocols. It is a successor to the ZSpy program.
=cut
BEGIN {
ZOOM::Log::mask_str("irspy");
ZOOM::Log::mask_str("irspy_debug");
ZOOM::Log::mask_str("irspy_event");
ZOOM::Log::mask_str("irspy_unhandled");
ZOOM::Log::mask_str("irspy_test");
ZOOM::Log::mask_str("irspy_task");
}
sub new {
my $class = shift();
my($dbname, $user, $password, $activeSetSize) = @_;
my @options;
push @options, (user => $user, password => $password)
if defined $user;
my $conn = new ZOOM::Connection($dbname, 0, @options)
or die "$0: can't connection to IRSpy database 'dbname'";
my $xslt = new XML::LibXSLT;
$xslt->register_function($ZOOM::IRSpy::Utils::IRSPY_NS, 'strcmp',
\&ZOOM::IRSpy::Utils::xslt_strcmp);
my $libxml = new XML::LibXML;
my $xsl_doc = $libxml->parse_file($irspy_to_zeerex_xsl);
my $irspy_to_zeerex_style = $xslt->parse_stylesheet($xsl_doc);
my $this = bless {
conn => $conn,
query => "cql.allRecords=1", # unless overridden
targets => undef, # Filled in later if targets() is
# called; used only to keep state from
# targets() until initialise() is
# called.
connections => undef, # Filled in by initialise()
queue => undef, # Filled in by initialise()
libxml => $libxml,
irspy_to_zeerex_style => $irspy_to_zeerex_style,
test => undef, # Filled in by initialise()
tests => undef, # Tree of tests to be executed
activeSetSize => defined $activeSetSize ? $activeSetSize : 10,
}, $class;
$this->log("irspy", "starting up with database '$dbname'");
return $this;
}
sub log {
my $this = shift();
ZOOM::Log::log(@_);
}
sub find_targets {
my $this = shift();
my($query) = @_;
$this->{query} = $query;
}
# Explicitly nominate a set of targets to check, overriding the
# default which is to re-check everything in the database. Each
# target already in the database results in the existing record being
# updated; each new target causes a new record to be added.
#
sub targets {
my $this = shift();
my(@targets) = @_;
$this->log("irspy", "setting explicit list of targets ",
join(", ", map { "'$_'" } @targets));
my @qlist;
foreach my $target (@targets) {
my($protocol, $host, $port, $db, $newtarget) =
_parse_target_string($target);
if ($newtarget ne $target) {
$this->log("irspy_debug", "rewriting '$target' to '$newtarget'");
$target = $newtarget; # This is written through the ref
}
push @qlist, cql_target($protocol, $host, $port, $db);
}
$this->{targets} = \@targets;
$this->{query} = join(" or ", @qlist);
}
# Also used by ZOOM::IRSpy::Record
sub _parse_target_string {
my($target) = @_;
my($protocol, $host, $port, $db) = ($target =~ /(.*?):(.*?):(.*?)\/(.*)/);
if (!defined $host) {
$port = 210;
($protocol, $host, $db) = ($target =~ /(.*?):(.*?)\/(.*)/);
$target = irspy_make_identifier($protocol, $host, $port, $db);
}
die "$0: invalid target string '$target'"
if !defined $host;
return ($protocol, $host, $port, $db, $target);
}
# Records must be fetched for all records satisfying $this->{query} If
# $this->{targets} is already set (i.e. a specific list of targets to
# check was specified by a call to targets()), then new, empty records
# will be made for any targets that are not already in the database.
#
sub initialise {
my $this = shift();
my($tname) = @_;
$tname = "Main" if !defined $tname;
$this->{test} = $tname;
$this->{tree} = $this->_gather_tests($tname)
or die "No tests defined for '$tname'";
$this->{tree}->resolve();
#$this->{tree}->print(0);
my $timeout = "ZOOM::IRSpy::Test::$tname"->timeout();
my @targets;
my $targets = $this->{targets};
if (defined $targets) {
@targets = @$targets;
delete $this->{targets};
} else {
my $rs = $this->{conn}->search(new ZOOM::Query::CQL($this->{query}));
$this->log("irspy", "'", $this->{query}, "' found ",
$rs->size(), " target records");
delete $this->{query};
foreach my $i (1 .. $rs->size()) {
push @targets, render_record($rs, $i-1, "id");
}
}
my $n = $this->{activeSetSize};
$n = @targets if $n == 0 || $n > @targets;
my @connections;
foreach my $i (1..$n) {
push @connections, create ZOOM::IRSpy::Connection($this,
shift @targets,
async => 1,
timeout => $timeout);
}
$this->{connections} = \@connections;
$this->{queue} = \@targets;
}
sub _irspy_to_zeerex {
my $this = shift();
my($conn, $save_xml) = @_;
my $irspy_doc = $conn->record()->{zeerex}->ownerDocument;
if ($save_xml) {
unlink('/tmp/irspy_orig.xml');
open FH, '>/tmp/irspy_orig.xml'
or die "can't write irspy_orig.xml: $!";
print FH $irspy_doc->toString();
close FH;
}
my %params = ();
my $result = $this->{irspy_to_zeerex_style}->transform($irspy_doc, %params);
if ($save_xml) {
unlink('/tmp/irspy_transformed.xml');
open FH, '>/tmp/irspy_transformed.xml'
or die "can't write irspy_transformed.xml: $!";
print FH $result->toString();
close FH;
}
return $result->documentElement();
}
sub _rewrite_record {
my $this = shift();
my($conn) = @_;
$conn->log("irspy", "rewriting XML record");
my $rec = $this->_irspy_to_zeerex($conn, $ENV{IRSPY_SAVE_XML});
# Since IRSpy can run for a long time between writes back to the
# database, it's quite possible for the server to have closed the
# connection as idle. So re-establish it if necessary.
$this->{conn}->connect($conn->option("host"));
_really_rewrite_record($this->{conn}, $rec);
$conn->log("irspy", "rewrote XML record");
}
sub _really_rewrite_record {
my($conn, $rec, $oldid) = @_;
my $p = $conn->package();
$p->option(action => "specialUpdate");
my $xml = $rec->toString();
$p->option(record => $xml);
$p->send("update");
$p->destroy();
# This is the expression in the ID-making stylesheet
# ../../zebra/zeerex2id.xsl
my $xc = irspy_xpath_context($rec);
my $id = irspy_record2identifier($xc);
if (defined $oldid && $id ne $oldid) {
warn "IDs differ (old='$oldid' new='$id')";
# Delete old record;
### Should use same mechanism as delete.mc
my $p = $conn->package();
$p->option(action => "recordDelete");
$p->option(recordIdOpaque => $oldid);
$p->option(record => "
\n
$xml\n"; } } # The approach: gather declarative information about test hierarchy, # then go into a loop. In the loop, we ensure that each connection is # running a test, and within that test a task, until its list of tests # is exhausted. No individual test ever calls wait(): tests just queue # up tasks and return immediately. When the tasks are run (one at a # time on each connection) they generate events, and it is these that # are harvested by ZOOM::event(). Since each connection knows what # task it is running, it can invoke the appropriate callbacks. # Callbacks return a ZOOM::IRSpy::Status value which tells the main # loop how to continue. # # Invariants: # While a connection is running a task, its current_task() # points at the task structure. When it finishes its task, # next_task() is pointed at the next task to execute (if there # is one), and its current_task() is set to zero. When the next # task is executed, the connection's next_task() is set to zero # and its current_task() pointed to the task structure. # current_task() and next_task() are both zero only when there # are no more queued tasks, which is when a new test is # started. # # Each connection's current test is stored in its # "current_test_address" option. The next test to execute is # calculated by walking the declarative tree of tests. This # option begins empty; the "next test" after this is of course # the root test. # sub check { my $this = shift(); my $topname = $this->{tree}->name(); my $timeout = "ZOOM::IRSpy::Test::$topname"->timeout(); $this->log("irspy", "beginnning with test '$topname' (timeout $timeout)"); my $nskipped = 0; my @conn = @{ $this->{connections} }; my $nruns = 0; ROUND_AND_ROUND_WE_GO: while (1) { my @copy_conn = @conn; # avoid alias problems after splice() my $nconn = scalar(@copy_conn); foreach my $i0 (0 .. $#copy_conn) { my $conn = $copy_conn[$i0]; #print "connection $i0 of $nconn/", scalar(@conn), " is $conn\n"; next if !defined $conn; if (!$conn->current_task()) { if (!$conn->next_task()) { # Out of tasks: we need a new test NEXT_TEST: my $address = $conn->option("current_test_address"); my $nextaddr; if (!defined $address) { $nextaddr = ""; } else { $conn->log("irspy_test", "checking for next test after '$address'"); $nextaddr = $this->_next_test($address); } if (!defined $nextaddr) { $conn->log("irspy", "has no more tests: removing"); $this->_rewrite_record($conn); $conn->option(rewrote_record => 1); if (@{ $this->{queue} } == 0) { # Do not destroy: we need this for later sanity checks splice @conn, $i0, 1; } else { $conn->destroy(); $conn[$i0] = create ZOOM::IRSpy::Connection($this, shift @{ $this->{queue} }, async => 1, timeout => $timeout); $conn[$i0]->option(current_test_address => ""); $conn[$i0]->log("irspy", "entering active pool - ", scalar(@{ $this->{queue} }), " targets remain in queue"); } next; } my $node = $this->{tree}->select($nextaddr) or die "invalid nextaddr '$nextaddr'"; $conn->option(current_test_address => $nextaddr); my $tname = $node->name(); $conn->log("irspy_test", "starting test '$nextaddr' = $tname"); my $tasks = $conn->tasks(); my $oldcount = @$tasks; "ZOOM::IRSpy::Test::$tname"->start($conn); $tasks = $conn->tasks(); if (@$tasks > $oldcount) { # Prepare to start the first of the newly added tasks $conn->next_task($tasks->[$oldcount]); } else { $conn->log("irspy_task", "no tasks added by new test $tname"); goto NEXT_TEST; } } my $task = $conn->next_task(); die "no next task queued for $conn" if !defined $task; $conn->log("irspy_task", "preparing task $task"); $conn->next_task(0); $conn->current_task($task); $task->run(); } } NEXT_EVENT: my $i0 = ZOOM::event(\@conn); $this->log("irspy_event", "ZOOM_event(", scalar(@conn), " connections) = $i0"); if ($i0 < 1) { my %messages = ( 0 => "no events remain", -1 => "ZOOM::event() argument not a reference", -2 => "ZOOM::event() reference not an array", -3 => "no connections remain", -4 => "too many connections for ZOOM::event()", ); my $message = $messages{$i0} || "ZOOM::event() returned $i0"; $this->log("irspy", $message); last; } my $conn = $conn[$i0-1]; my $ev = $conn->last_event(); my $evstr = ZOOM::event_str($ev); $conn->log("irspy_event", "event $ev ($evstr)"); goto NEXT_EVENT if $ev != ZOOM::Event::ZEND; my $task = $conn->current_task(); die "$conn has no current task for event $ev ($evstr)" if !$task; my $res; eval { $conn->check() }; if ($@ && ref $@ && $@->isa("ZOOM::Exception")) { my $sub = $task->{cb}->{exception}; die $@ if !defined $sub; $res = &$sub($conn, $task, $task->udata(), $@); } elsif ($@) { die "Unexpected non-ZOOM exception: " . ref($@) . " ($@)"; } else { my $sub = $task->{cb}->{$ev}; if (!defined $sub) { $conn->log("irspy_unhandled", "event $ev ($evstr)"); next; } $res = &$sub($conn, $task, $task->udata(), $ev); } if ($res == ZOOM::IRSpy::Status::OK) { # Nothing to do -- life continues } elsif ($res == ZOOM::IRSpy::Status::TASK_DONE) { my $task = $conn->current_task(); die "no task for TASK_DONE on $conn" if !$task; die "next task already defined for $conn" if $conn->next_task(); $conn->log("irspy_task", "completed task $task"); $conn->next_task($task->{next}); $conn->current_task(0); } elsif ($res == ZOOM::IRSpy::Status::TEST_GOOD || $res == ZOOM::IRSpy::Status::TEST_BAD) { my $x = ($res == ZOOM::IRSpy::Status::TEST_GOOD) ? "good" : "bad"; $conn->log("irspy_task", "test ended during task $task ($x)"); $conn->log("irspy_test", "test completed ($x)"); $conn->current_task(0); $conn->next_task(0); if ($res == ZOOM::IRSpy::Status::TEST_BAD) { my $address = $conn->option('current_test_address'); $conn->log("irspy", "top-level test failed!") if $address eq ""; my $node = $this->{tree}->select($address); my $skipcount = 0; while (defined $node->next() && length($node->next()->address()) >= length($address)) { $conn->log("irspy_debug", "skipping from '", $node->address(), "' to '", $node->next()->address(), "'"); $node = $node->next(); $skipcount++; } $conn->option(current_test_address => $node->address()); $conn->log("irspy_test", "skipped $skipcount tests"); $nskipped += $skipcount; } } elsif ($res == ZOOM::IRSpy::Status::TEST_SKIPPED) { $conn->log("irspy_test", "test skipped during task $task"); $conn->current_task(0); $conn->next_task(0); $nskipped++; } else { die "unknown callback return-value '$res'"; } } $this->log("irspy", "exiting main loop"); # Sanity checks: none of the following should ever happen my $finished = 1; $this->log("irspy", "performing end-of-run sanity-checks"); foreach my $conn (@conn) { my $test = $conn->option("current_test_address"); my $next = $this->_next_test($test); if (defined $next) { $this->log("irspy", "$conn (in test '$test') has queued test '$next'"); $finished = 0; } if (my $task = $conn->current_task()) { $this->log("irspy", "$conn still has an active task $task"); $finished = 0; } if (my $task = $conn->next_task()) { $this->log("irspy", "$conn still has a queued task $task"); $finished = 0; } if (!$conn->is_idle()) { $this->log("irspy", "$conn still has ZOOM-C level tasks queued: see below"); $finished = 0; } my $ev = $conn->peek_event(); if ($ev != 0 && $ev != ZOOM::Event::ZEND) { my $evstr = ZOOM::event_str($ev); $this->log("irspy", "$conn has event $ev ($evstr) waiting"); $finished = 0; } if (!$conn->option("rewrote_record")) { $this->log("irspy", "$conn did not rewrite its ZeeRex record"); $finished = 0; } } # This really shouldn't be necessary, and in practice it rarely # helps, but it's belt and braces. (For now, we don't do this # hence the zero in the $nruns check). if (!$finished) { if (++$nruns < 0) { $this->log("irspy", "back into main loop, ${nruns}th time"); goto ROUND_AND_ROUND_WE_GO; } else { $this->log("irspy", "bailing after $nruns main-loop runs"); } } # This shouldn't happen emit anything either: while ((my $i1 = ZOOM::event(\@conn)) > 0) { my $conn = $conn[$i1-1]; my $ev = $conn->last_event(); my $evstr = ZOOM::event_str($ev); $this->log("irspy", "$conn still has ZOOM-C level task queued: $ev ($evstr)") if $ev != ZOOM::Event::ZEND; } return $nskipped; } # Exactly equivalent to ZOOM::event() except that it is tolerant to # undefined values in the array being passed in. # sub __UNUSED_tolerant_ZOOM_event { my($connref) = @_; my(@conn, @map); foreach my $i (0 .. @$connref-1) { my $conn = $connref->[$i]; if (defined $conn) { push @conn, $conn; push @map, $i; } } my $res = ZOOM::event(\@conn); return $res if $res <= 0; my $res2 = $map[$res-1] + 1; print STDERR "*** tolerant_ZOOM_event() returns $res->$res2\n"; return $res2; } sub _gather_tests { my $this = shift(); my($tname, @ancestors) = @_; die("$0: test-hierarchy loop detected: " . join(" -> ", @ancestors, $tname)) if grep { $_ eq $tname } @ancestors; my $slashSeperatedTname = $tname; $slashSeperatedTname =~ s/::/\//g; my $fullName = "ZOOM/IRSpy/Test/$slashSeperatedTname.pm"; eval { require $fullName; }; if ($@) { $this->log("irspy", "couldn't require '$fullName': $@"); $this->log("warn", "can't load test '$tname': skipping", $@ =~ /^Can.t locate/ ? () : " ($@)"); return undef; } $this->log("irspy", "adding test '$tname'"); my @subnodes; foreach my $subtname ("ZOOM::IRSpy::Test::$tname"->subtests($this)) { my $subtest = $this->_gather_tests($subtname, @ancestors, $tname); push @subnodes, $subtest if defined $subtest; } return new ZOOM::IRSpy::Node($tname, @subnodes); } # These next three should arguably be Node methods sub _next_test { my $this = shift(); my($address, $omit_child) = @_; # Try first child if (!$omit_child) { my $maybe = $address eq "" ? "0" : "$address:0"; return $maybe if $this->{tree}->select($maybe); } # The top-level node has no successor or parent return undef if $address eq ""; # Try next sibling child my @components = split /:/, $address; my $last = pop @components; my $maybe = join(":", @components, $last+1); return $maybe if $this->{tree}->select($maybe); # This node is exhausted: try the parent's successor return $this->_next_test(join(":", @components), 1) } sub _last_sibling_test { my $this = shift(); my($address) = @_; return undef if !defined $this->_next_sibling_test($address); my $nskipped = 0; while (1) { my $maybe = $this->_next_sibling_test($address); last if !defined $maybe; $nskipped++; $address = $maybe; $this->log("irspy", "skipping $nskipped tests to '$address'"); } return ($address, $nskipped); } sub _next_sibling_test { my $this = shift(); my($address) = @_; my @components = split /:/, $address; my $last = pop @components; my $maybe = join(":", @components, $last+1); return $maybe if $this->{tree}->select($maybe); return undef; } =head1 SEE ALSO ZOOM::IRSpy::Record, ZOOM::IRSpy::Web, ZOOM::IRSpy::Test, ZOOM::IRSpy::Maintenance. The ZOOM-Perl module, http://search.cpan.org/~mirk/Net-Z3950-ZOOM/ The Zebra Database, http://indexdata.com/zebra/ =head1 AUTHOR Mike Taylor, E