# $Id: IRSpy.pm,v 1.90 2008-07-16 11:42:13 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 = '1.01'; 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 modn => undef, # Filled in by restrict_modulo() modi => undef, # Filled in by restrict_modulo() 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() timeout => 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); } sub restrict_modulo { my $this = shift(); my($n, $i) = @_; $this->{modn} = $n; $this->{modi} = $i; } # 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); $this->{timeout} = "ZOOM::IRSpy::Test::$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; $this->{queue} = \@targets; $this->{connections} = []; while (@{ $this->{connections} } < $n) { my $conn = $this->_next_connection(); last if !defined $conn; push @{ $this->{connections} }, $conn; } } sub _next_connection { my $this = shift(); my $target; my $n = $this->{modn}; my $i = $this->{modi}; if (!defined $n) { $target = shift @{ $this->{queue} }; return undef if !defined $target; } else { while (1) { $target = shift @{ $this->{queue} }; return undef if !defined $target; my $h = _hash($target); my $hmodn = $h % $n; last if $hmodn == $i; #$this->log("irspy", "'$target' hash $h % $n = $hmodn != $i"); } } die "oops -- target is undefined" if !defined $target; return create ZOOM::IRSpy::Connection($this, $target, async => 1, timeout => $this->{timeout}); } sub _hash { my($target) = @_; my $n = 0; foreach my $s (split //, $target) { $n += ord($s); } return $n; } 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='$id')"; _delete_record($conn, $oldid); } $p = $conn->package(); $p->send("commit"); $p->destroy(); if (0) { $xml =~ s/&/&/g; $xml =~ s//>/g; print "Updated $conn with xml=
\n
$xml
\n"; } } sub _delete_record { my($conn, $id) = @_; # We can't delete records using recordIdOpaque, since character # sets are handled differently here in extended services from how # they are used in the Alvis filter's record-parsing, and so # non-ASCII characters come out differently in the two contexts. # Instead, we must send a record whose contents indicate the ID of # that which we wish to delete. There are two ways, both # unsatisfactory: we could either fetch the actual record them # resubmit it in the deletion request (which wastes a search and a # fetch) or we could build a record by hand from the parsed-out # components (which is error-prone and which I am not 100% certain # will work since the other contents of the record will be # different). The former evil seems to be the lesser. warn "$conn deleting record '$id'"; my $rs = $conn->search(new ZOOM::Query::CQL(cql_target($id))); die "no such ID '$id'" if $rs->size() == 0; my $rec = $rs->record(0); my $xml = $rec->render(); my $p = $conn->package(); $p->option(action => "recordDelete"); $p->option(record => $xml); $p->send("update"); $p->destroy(); $p = $conn->package(); $p->send("commit"); $p->destroy(); } # 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 = $this->{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); my $newconn = $this->_next_connection(); if (!defined $newconn) { # Do not destroy: needed for later sanity checks splice @conn, $i0, 1; } else { $conn->destroy(); $conn[$i0] = $newconn; $conn[$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, Emike@indexdata.comE =head1 COPYRIGHT AND LICENSE Copyright (C) 2006 by Index Data ApS. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.7 or, at your option, any later version of Perl 5 you may have available. =cut 1;