X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;ds=sidebyside;f=SimpleServer.pm;h=d6546e73c726c0d7425d0e03a4d407ff156fbdda;hb=2a49c3688c23f4e1c3dcf23fc599ee3286df2811;hp=f5b68668034b8bc790cc6472c9b4010c3573fc75;hpb=2edffd526d9e0ced8031fb5e3fcb658b93a69b39;p=simpleserver-moved-to-github.git diff --git a/SimpleServer.pm b/SimpleServer.pm index f5b6866..d6546e7 100644 --- a/SimpleServer.pm +++ b/SimpleServer.pm @@ -25,6 +25,38 @@ ## ## +## $Log: SimpleServer.pm,v $ +## Revision 1.13 2002-03-06 11:02:04 mike +## Added simple README file, derived from POD comments in SimpleServer.pm +## Fixed my (Mike Taylor's) email address +## +## Revision 1.12 2002/03/05 20:52:22 sondberg +## Version 0.05 so that we can release the thing at CPAN. +## +## Revision 1.11 2002/03/05 20:49:56 sondberg +## Added a couple of lines of documentation. +## +## Revision 1.10 2002/02/28 11:21:57 mike +## Add RPN structure to search-handler argument hash. +## +## Revision 1.9 2001/08/29 11:48:36 sondberg +## Added routines +## +## Net::Z3950::SimpleServer::ScanSuccess +## Net::Z3950::SimpleServer::ScanPartial +## +## and a bit of documentation. +## +## Revision 1.8 2001/08/29 10:29:51 sondberg +## Added some documentation of scan. +## +## Revision 1.7 2001/08/24 14:00:20 sondberg +## Added support for scan. +## +## Revision 1.6 2001/03/13 14:17:15 sondberg +## Added support for GRS-1. +## + package Net::Z3950::SimpleServer; use strict; @@ -42,7 +74,7 @@ require AutoLoader; @EXPORT = qw( ); -$VERSION = '0.02'; +$VERSION = '0.05'; bootstrap Net::Z3950::SimpleServer $VERSION; @@ -52,19 +84,16 @@ my $count = 0; sub new { my $class = shift; - my $args = shift || croak "SimpleServer::new: Usage new(argument hash)"; - my $self = {}; + my %args = @_; + my $self = \%args; if ($count) { carp "SimpleServer.pm: WARNING: Multithreaded server unsupported"; } $count = 1; - $self->{INIT} = $args->{INIT}; - $self->{SEARCH} = $args->{SEARCH} || croak "SimpleServer.pm: ERROR: Unspecified search handler"; - $self->{FETCH} = $args->{FETCH} || croak "SimpleServer.pm: ERROR: Unspecified fetch handler"; - $self->{CLOSE} = $args->{CLOSE}; - $self->{PRESENT} = $args->{PRESENT}; + croak "SimpleServer.pm: ERROR: Unspecified search handler" unless defined($self->{SEARCH}); + croak "SimpleServer.pm: ERROR: Unspecified fetch handler" unless defined($self->{FETCH}); bless $self, $class; return $self; @@ -86,11 +115,28 @@ sub launch_server { if (defined($self->{PRESENT})) { set_present_handler($self->{PRESENT}); } + if (defined($self->{SCAN})) { + set_scan_handler($self->{SCAN}); + } start_server(@args); } +# Register packages that we will use in translated RPNs +package Net::Z3950::APDU::Query; +package Net::Z3950::APDU::OID; +package Net::Z3950::RPN::And; +package Net::Z3950::RPN::Or; +package Net::Z3950::RPN::AndNot; +package Net::Z3950::RPN::Term; +package Net::Z3950::RPN::Attributes; +package Net::Z3950::RPN::Attribute; + +# Must revert to original package for Autoloader's benefit +package Net::Z3950::SimpleServer; + + # Autoload methods go after =cut, and are processed by the autosplit program. 1; @@ -123,7 +169,7 @@ Net::Z3950::SimpleServer - Simple Perl API for building Z39.50 servers. my $set_id = $args->{SETNAME}; - my $record = fetch_a_record($args->{OFFSET); + my $record = fetch_a_record($args->{OFFSET}); $args->{RECORD} = $record; if (number_of_hits() == $args->{OFFSET}) { ## Last record in set? @@ -136,15 +182,13 @@ Net::Z3950::SimpleServer - Simple Perl API for building Z39.50 servers. ## Register custom event handlers: - my $handle = Net::Z3950::SimpleServer->new({ - INIT => \&my_init_handler, + my $z = new Net::Z3950::SimpleServer( INIT => \&my_init_handler, CLOSE => \&my_close_handler, SEARCH => \&my_search_handler, - FETCH => \&my_fetch_handler - }); + FETCH => \&my_fetch_handler); ## Launch server: - $handle->launch_server("ztest.pl", @ARGV); + $z->launch_server("ztest.pl", @ARGV); =head1 DESCRIPTION @@ -176,6 +220,7 @@ of events: - Search request - Present request - Fetching of records + - Scan request (browsing) - Closing down connection Note that only the Search and Fetch handler functions are required. @@ -192,17 +237,18 @@ output parameters. The Perl programmer specifies the event handles for the server by means of the the SimpleServer object constructor - my $handle = Net::Z3950::SimpleServer->new({ - INIT => \&my_init_handler, - CLOSE => \&my_close_handler, - SEARCH => \&my_search_handler, - PRESENT => \&my_present_handler, - FETCH => \&my_fetch_handler }); + my $z = new Net::Z3950::SimpleServer( + INIT => \&my_init_handler, + CLOSE => \&my_close_handler, + SEARCH => \&my_search_handler, + PRESENT => \&my_present_handler, + SCAN => \&my_scan_handler, + FETCH => \&my_fetch_handler); After the custom event handles are declared, the server is launched by means of the method - $handle->launch_server("MyServer.pl", @ARGV); + $z->launch_server("MyServer.pl", @ARGV); Notice, the first argument should be the name of your server script (for logging purposes), while the rest of the arguments @@ -260,6 +306,8 @@ mous hash. The structure is the following: DATABASES => ["xxx"], ## Reference to a list of data- ## bases to search QUERY => "query", ## The query expression + RPN => $obj, ## Blessed reference int the package + ## Net::Z3950::APDU::Query ## Response parameters: @@ -304,6 +352,11 @@ it is perfectly legal to not accept boolean operators, but you SHOULD try to return good error codes if you run into something you can't or won't support. +The RPN member is a blessed reference into the package Net::Z3950::APDU::Query. +By means of an augmented type of coding, you can easily construct a +parser of the incoming RPN. Take a look at samples/render-search.pl for +a sample implementation of such an augmented parser technique. + =head2 Present handler The presence of a present handler in a SimpleServer front-end is optional. @@ -388,6 +441,61 @@ these. NOTE: The record offset is 1-indexed - 1 is the offset of the first record in the set. +=head2 Scan handler + +A full featured Z39.50 server should support scan (or in some literature +browse). The client specifies a starting term of the scan, and the server +should return an ordered list of specified length consisting of terms +actually occurring in the data base. Each of these terms should be close +to or equal to the term originally specified. The quality of scan compared +to simple search is a guarantee of hits. It is simply like browsing through +an index of a book, you always find something! The parameters exchanged are + + $args = { + ## Client request + + HANDLE => $ref ## Reference to data structure + TERM => 'start', ## The start term + NUMBER => xx, ## Number of requested terms + POS => yy, ## Position of starting point + ## within returned list + STEP => 0, ## Step size + + ## Server response + + ERR_CODE => 0, ## Error code + ERR_STR => '', ## Diagnostic message + NUMBER => zz, ## Number of returned terms + STATUS => $status, ## ScanSuccess/ScanFailure + ENTRIES => $entries ## Referenced list of terms + }; + +where the term list is returned by reference in the scalar $entries, which +should point at a data structure of this kind, + + my $entries = [ + { TERM => 'energy', + OCCURRENCE => 5 }, + + { TERM => 'energy density', + OCCURRENCE => 6, }, + + { TERM => 'energy flow', + OCCURRENCE => 3 }, + + ... + + ... + ]; + +The $status flag should be assigned one of two values: + + Net::Z3950::SimpleServer::ScanSuccess On success (default) + Net::Z3950::SimpleServer::ScanPartial Less terms returned than requested + +The STEP member contains the requested number of entries in the term-list +between two adjacent entries in the response. + =head2 Close handler The argument hash recieved by the close handler has one element only: @@ -404,15 +512,12 @@ or something similar, this is the place to do it. =head1 AUTHORS Anders Sønderberg (sondberg@indexdata.dk) and Sebastian Hammer -(quinn@indexdata.dk). +(quinn@indexdata.dk). Substantial contributions made by Mike Taylor +(mike@miketaylor.org.uk). =head1 SEE ALSO -perl(1). - Any Perl module which is useful for accessing the database of your choice. =cut - -