# $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;
$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; $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, E