# $Id: IRSpy.pm,v 1.37 2006-10-26 13:39:13 sondberg Exp $ package ZOOM::IRSpy; use 5.008; use strict; use warnings; use Exporter 'import'; our @EXPORT_OK = qw(xml_encode irspy_xpath_context); 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::Record; our @ISA = qw(); our $VERSION = '0.02'; our $irspy_ns = 'http://indexdata.com/irspy/1.0'; 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 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"); print $spy->report_status(); =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) = @_; 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; 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, allrecords => 1, # unless overridden by targets() query => undef, # filled in later targets => undef, # filled in later connections => undef, # filled in later libxml => $libxml, irspy_to_zeerex_style => $xslt->parse_stylesheet($xsl_doc), tests => [], # stack of tests currently being executed }, $class; $this->log("irspy", "starting up with database '$dbname'"); return $this; } sub log { my $this = shift(); ZOOM::Log::log(@_); } # 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)); $this->{allrecords} = 0; my @qlist; foreach my $target (@targets) { my($host, $port, $db, $newtarget) = _parse_target_string($target); if ($newtarget ne $target) { $this->log("irspy_debug", "rewriting '$target' to '$newtarget'"); $target = $newtarget; # This is written through the ref } push @qlist, (qq[(host="$host" and port="$port" and path="$db")]); } $this->{targets} = \@targets; $this->{query} = join(" or ", @qlist); } # Also used by ZOOM::IRSpy::Record sub _parse_target_string { my($target) = @_; my($host, $port, $db) = ($target =~ /(.*?):(.*?)\/(.*)/); if (!defined $host) { $port = 210; ($host, $db) = ($target =~ /(.*?)\/(.*)/); $target = "$host:$port/$db"; } die "$0: invalid target string '$target'" if !defined $host; return ($host, $port, $db, $target); } # There are two cases. # # 1. A specific set of targets is nominated on the command line. # - Records must be fetched for those targets that are in the DB # - New, empty records must be made for those that are not. # - Updated records written to the DB may or may not be new. # # 2. All records in the database are to be checked. # - Records must be fetched for all targets in the DB # - Updated records written to the DB may not be new. # # That's all -- what could be simpler? # sub initialise { my $this = shift(); my %target2record; if ($this->{allrecords}) { # We need to check on every target in the database, which # means we need to do a "find all". According to the BIB-1 # semantics document at # http://www.loc.gov/z3950/agency/bib1.html # the query # @attr 2=103 @attr 1=1035 x # should find all records, but it seems that Zebra doesn't # support this. Furthermore, when using the "alvis" filter # (as we do for IRSpy) it doesn't support the use of any BIB-1 # access point -- not even 1035 "everywhere" -- so instead we # hack together a search that we know will find all records. $this->{query} = "port=?*"; } else { # Prepopulate the target map with nulls so that after we fill # in what we can from the database query, we know which target # IDs we need new records for. foreach my $target (@{ $this->{targets} }) { $target2record{lc($target)} = undef; } } $this->log("irspy_debug", "query '", $this->{query}, "'"); my $rs = $this->{conn}->search(new ZOOM::Query::CQL($this->{query})); delete $this->{query}; # No longer needed at all $this->log("irspy_debug", "found ", $rs->size(), " target records"); foreach my $i (1 .. $rs->size()) { my $target = _render_record($rs, $i-1, "id"); my $zeerex = _render_record($rs, $i-1, "zeerex"); #print STDERR "making '$target' record with '$zeerex'\n"; $target2record{lc($target)} = new ZOOM::IRSpy::Record($this, $target, $zeerex); push @{ $this->{targets} }, $target if $this->{allrecords}; } # Make records for targets not previously in the database foreach my $target (keys %target2record) { my $record = $target2record{$target}; if (!defined $record) { $this->log("irspy_debug", "made new record for '$target'"); $target2record{$target} = new ZOOM::IRSpy::Record($this, $target); } else { $this->log("irspy_debug", "using existing record for '$target'"); } } my @connections; foreach my $target (@{ $this->{targets} }) { my $conn = create ZOOM::IRSpy::Connection($this, async => 1); $conn->option(host => $target); my $record = delete $target2record{lc($target)}; $conn->record($record); push @connections, $conn; } die("remaining target2record = { " . join(", ", map { "$_ ->'" . $target2record{$_}. "'" } sort keys %target2record) . " }") if %target2record; $this->{connections} = \@connections; delete $this->{targets}; # The information is now in {connections} } sub _render_record { my($rs, $which, $elementSetName) = @_; # There is a slight race condition here on the element-set name, # but it shouldn't be a problem as this is (currently) only called # from parts of the program that run single-threaded. my $old = $rs->option(elementSetName => $elementSetName); my $rec = $rs->record($which); $rs->option(elementSetName => $old); return $rec->render(); } sub _irspy_to_zeerex { my ($this, $conn) = @_; my $irspy_doc = $conn->record()->{zeerex}->ownerDocument; my %params = (); my $result = $this->{irspy_to_zeerex_style}->transform($irspy_doc, %params); return $result->documentElement(); } sub _rewrite_record { my $this = shift(); my($conn) = @_; $conn->log("irspy", "rewriting XML record"); my $rec = $this->_irspy_to_zeerex($conn); my $p = $this->{conn}->package(); $p->option(action => "specialUpdate"); my $xml = $rec->toString(); $p->option(record => $xml); $p->send("update"); $p->destroy(); $p = $this->{conn}->package(); $p->send("commit"); $p->destroy(); if (0) { $xml =~ s/&/&/g; $xml =~ s//>/g; print "Updated $conn with xml=
\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 $this = shift(); my($tname) = @_; $tname = "Main" if !defined $tname; $this->{tree} = $this->_gather_tests($tname) or die "No tests defined"; #$this->{tree}->print(0); my $nskipped = 0; my @conn = @{ $this->{connections} }; 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 $conn\n"; if (!$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 { $this->log("irspy_test", "checking for next test after '$address'"); $nextaddr = $this->_next_test($address); } if (!defined $nextaddr) { $conn->log("irspy", "has no more tests: removing"); splice @conn, $i0, 1; $this->_rewrite_record($conn); 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(); } # Do we need to test $conn->is_idle()? I don't think so! } my $i0 = ZOOM::event(\@conn); $this->log("irspy_event", "ZOOM_event(", scalar(@conn), " connections) = $i0"); last if $i0 == 0 || $i0 == -3; # no events or no connections my $conn = $conn[$i0-1]; my $ev = $conn->last_event(); my $evstr = ZOOM::event_str($ev); $conn->log("irspy_event", "event $ev ($evstr)"); my $task = $conn->current_task(); die "$conn has no current task for event $ev ($evstr)" if !$task; eval { $conn->_check() }; if ($@ && ($ev == ZOOM::Event::RECV_DATA || $ev == ZOOM::Event::RECV_APDU || $ev == ZOOM::Event::ZEND)) { # An error in, say, a search response, becomes visible to # ZOOM before the Receive Data event is sent and persists # until after the End, which means that successive events # each report the same error. So we just ignore errors on # "unimportant" events. ### But this doesn't work for, # say, a Connection Refused, as the only event that shows # us this error is the End. $conn->log("irspy_event", "ignoring error ", "on event $ev ($evstr): $@"); next; } my $res; if ($@) { my $sub = $task->{cb}->{exception}; die $@ if !defined $sub; $res = &$sub($conn, $task, $task->udata(), $@); } 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 = $conn->option('current_test_address'); ($address, my $n) = $this->_last_sibling_test($address); if (defined $address) { $conn->log("irspy_test", "skipped $n tests"); $conn->option(current_test_address => $address); $nskipped += $n; } } } else { die "unknown callback return-value '$res'"; } } $this->log("irspy", "exiting main loop"); return $nskipped; } sub _gather_tests { my $this = shift(); my($tname, @ancestors) = @_; die("$0: test-hierarchy loop detected: " . join(" -> ", @ancestors, $tname)) if grep { $_ eq $tname } @ancestors; eval { my $slashSeperatedTname = $tname; $slashSeperatedTname =~ s/::/\//g; require "ZOOM/IRSpy/Test/$slashSeperatedTname.pm"; }; if ($@) { $this->log("warn", "can't load test '$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++; $this->log("irspy", "skipping $nskipped tests to '$address'"); $address = $maybe; } return ($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; } # Utility functions follow, exported for use of web UI # I can't -- just can't, can't, can't -- believe that this function # isn't provided by one of the core XML modules. But the evidence all # says that it's not: among other things, XML::Generator and # Template::Plugin both roll their own. So I will do likewise. D'oh! # sub xml_encode { my ($text) = @_; $text =~ s/&/&/g; $text =~ s//>/g; $text =~ s/['']/'/g; $text =~ s/[""]/"/g; return $text; } sub irspy_xpath_context { my($zoom_record) = @_; my $xml = $zoom_record->render(); my $parser = new XML::LibXML(); my $doc = $parser->parse_string($xml); my $root = $doc->getDocumentElement(); my $xc = XML::LibXML::XPathContext->new($root); $xc->registerNs(e => 'http://explain.z3950.org/dtd/2.0/'); return $xc; } =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;