src/URL/URLhandler.pm

# Interface
# ---------
# new(cache)       : A new urlhandler with a defined default cahce directory
# download(url,[location]) : as get but always download
# get(url,[location]) : download from the specified url to cache or location
#                       return the full url path name incl. any base expansion
#                       and the filename downloaded to
# setbase(urlstring) : set a base url type
# unsetbase(type)  : deactivate a previously set base
# currentbase(type) : return the current base for the given type
#
# ----------------------------------------------------------------------

package URL::URLhandler;
require 5.004;
use Utilities::AddDir;
use URL::URLcache;
use URL::URLclass;
use Carp;

sub new {
        my $class=shift;
        my $cache=shift;
        $self={};
        bless $self, $class;
        $self->init($cache);
        return $self;
}

sub init {
        use Utilities::AddDir;
        my $self=shift;
        my $cache=shift;
        $self->{cache}=$cache;
        $self->{cachestore}=$self->{cache}->filestore();
        use URL::URL_cvs;
        use URL::URL_file;
        use URL::URL_test;
        $self->{urlmodules}={
                        'cvs' => 'URL::URL_cvs',
                        'file' => 'URL::URL_file',
                        'test' => 'URL::URL_test'
                };
}

sub get {
        my $self=shift;
        my $origurl=shift;
        my $file="";

        my $url=URL::URLclass->new($origurl);
        my $type=$url->type();
        $url->merge($self->currentbase($type));
        my $fullurl=$url->url();

        $file=$self->{cache}->file($fullurl);
        if ( $file eq "" ) {
          ($fullurl,$file)=$self->download($origurl, @_);
        }
        return ($fullurl, $file);
}

sub download {
        my $self=shift;
        my $origurl=shift;

        # Process the URL string
        my $url=URL::URLclass->new($origurl);
        my $type=$url->type();
        $urltypehandler=$self->_typehandler($type);
        $url->merge($self->currentbase($type));

        # Generate a location name if not provided 
        $nocache=1;
        if ( @_ ) {
           $location=shift;
           $nocache=0; # dont cache if downloaded to an external location
        }
        else {
           $location=$self->{cache}->filename($url->url());
        }
        # -- get the file from the appropriate handler
        if ( defined $urltypehandler ) {
             # Call the download module
             $file=eval{$urltypehandler->get($url, $location)}; 
        } 

        # now register it in the cache if successful
        if ( $file && $nocache) {
          $self->{cache}->store($url->url(), $location);
        }
        return ($url->url(), $file);
}

sub setbase {
        my $self=shift;
        my $partialurl=shift;

        my $base=URL::URLclass->new($partialurl);
        my $type=$base->type();
        $self->checktype($type);
        # make a new base-url object
        push @{$self->{"basestack"}{$type}}, $base;
}

sub unsetbase {
        my $self=shift;
        my $type=shift;
        my $oref;

        $self->checktype($type);
        # pop off the stack and call the unset base method
        if ( $#{$self->{basestack}{$type}} >=0 ) {
           my $base=pop @{$self->{basestack}{$type}};
           undef $base;
        }
        else {
           die "URLhandler error: Unable to unset type $type\n";
        }
        # remove the stack if its empty
        if ( $#{$self->{basestack}{$type}} == -1 ) {
          delete $self->{basestack}{$type};
        }
}

sub currentbase {
        my $self=shift;
        my $type=shift;
        my $rv;

        if ( exists $self->{basestack}{$type} ) {
          $rv=${$self->{basestack}{$type}}[$#{$self->{basestack}{$type}}];
        }
        else {
          $rv=undef;
        }
        return $rv;
}

sub checktype($type) {
        my $self=shift;
        my $type=shift;

        # Check type is supported
        if ( ! exists $self->{urlmodules}{$type} ) {
          die "URLhandler error: Unsupported type $type\n";
        }
}

sub _typehandler {
        my $self=shift;
        my $type=shift;

        $self->checktype($type);

        # instantiate only if it dosnt already exist;
        if ( exists $self->{'urlobjs'}{$type} ) {
                $self->{'urlobjs'}{$type};
        }       
        else {
                $self->{'urlobjs'}{$type}=$self->{urlmodules}{$type}->new();
        }
}
Revision:	1.15
Committed:	Fri Aug 4 07:47:43 2000 UTC (24 years, 9 months ago) by williamc
Content type:	text/plain
Branch:	MAIN
CVS Tags:	ProtoEnd
Branch point for:	HPWbranch
Changes since 1.14:	+8 -13 lines
Log Message:	working versions
#	User	Rev	Content
1	williamc	1.7	# Interface
2	williamc	1.1	# ---------
3	williamc	1.7	# new(cache) : A new urlhandler with a defined default cahce directory
4	williamc	1.11	# download(url,[location]) : as get but always download
5	williamc	1.9	# get(url,[location]) : download from the specified url to cache or location
6			# return the full url path name incl. any base expansion
7			# and the filename downloaded to
8	williamc	1.15	# setbase(urlstring) : set a base url type
9	williamc	1.1	# unsetbase(type) : deactivate a previously set base
10	williamc	1.9	# currentbase(type) : return the current base for the given type
11	williamc	1.1	#
12			# ----------------------------------------------------------------------
13
14	williamc	1.5	package URL::URLhandler;
15	williamc	1.1	require 5.004;
16			use Utilities::AddDir;
17	williamc	1.9	use URL::URLcache;
18			use URL::URLclass;
19	williamc	1.1	use Carp;
20
21			sub new {
22			my $class=shift;
23			my $cache=shift;
24			$self={};
25			bless $self, $class;
26			$self->init($cache);
27			return $self;
28			}
29
30			sub init {
31			use Utilities::AddDir;
32			my $self=shift;
33			my $cache=shift;
34			$self->{cache}=$cache;
35	williamc	1.7	$self->{cachestore}=$self->{cache}->filestore();
36	williamc	1.2	use URL::URL_cvs;
37			use URL::URL_file;
38	williamc	1.13	use URL::URL_test;
39	williamc	1.2	$self->{urlmodules}={
40	williamc	1.5	'cvs' => 'URL::URL_cvs',
41	williamc	1.7	'file' => 'URL::URL_file',
42	williamc	1.13	'test' => 'URL::URL_test'
43	williamc	1.2	};
44	williamc	1.1	}
45
46	williamc	1.7	sub get {
47	williamc	1.4	my $self=shift;
48	williamc	1.9	my $origurl=shift;
49	williamc	1.11	my $file="";
50	williamc	1.9
51	williamc	1.11	my $url=URL::URLclass->new($origurl);
52			my $type=$url->type();
53	williamc	1.15	$url->merge($self->currentbase($type));
54	williamc	1.11	my $fullurl=$url->url();
55
56	williamc	1.12	$file=$self->{cache}->file($fullurl);
57			if ( $file eq "" ) {
58	williamc	1.11	($fullurl,$file)=$self->download($origurl, @_);
59			}
60			return ($fullurl, $file);
61			}
62
63			sub download {
64			my $self=shift;
65			my $origurl=shift;
66
67			# Process the URL string
68			my $url=URL::URLclass->new($origurl);
69	williamc	1.9	my $type=$url->type();
70			$urltypehandler=$self->_typehandler($type);
71	williamc	1.15	$url->merge($self->currentbase($type));
72	williamc	1.9
73			# Generate a location name if not provided
74	williamc	1.12	$nocache=1;
75	williamc	1.9	if ( @_ ) {
76			$location=shift;
77	williamc	1.12	$nocache=0; # dont cache if downloaded to an external location
78	williamc	1.9	}
79			else {
80			$location=$self->{cache}->filename($url->url());
81			}
82	williamc	1.11	# -- get the file from the appropriate handler
83	williamc	1.9	if ( defined $urltypehandler ) {
84			# Call the download module
85			$file=eval{$urltypehandler->get($url, $location)};
86			}
87	williamc	1.4
88	williamc	1.9	# now register it in the cache if successful
89	williamc	1.12	if ( $file && $nocache) {
90	williamc	1.11	$self->{cache}->store($url->url(), $location);
91	williamc	1.9	}
92	williamc	1.10	return ($url->url(), $file);
93	williamc	1.4	}
94
95	williamc	1.9	sub setbase {
96	williamc	1.1	my $self=shift;
97	williamc	1.15	my $partialurl=shift;
98	williamc	1.7
99	williamc	1.15	my $base=URL::URLclass->new($partialurl);
100			my $type=$base->type();
101	williamc	1.9	$self->checktype($type);
102	williamc	1.15	# make a new base-url object
103	williamc	1.10	push @{$self->{"basestack"}{$type}}, $base;
104	williamc	1.9	}
105	williamc	1.1
106	williamc	1.9	sub unsetbase {
107			my $self=shift;
108			my $type=shift;
109			my $oref;
110	williamc	1.7
111	williamc	1.9	$self->checktype($type);
112			# pop off the stack and call the unset base method
113			if ( $#{$self->{basestack}{$type}} >=0 ) {
114			my $base=pop @{$self->{basestack}{$type}};
115			undef $base;
116			}
117			else {
118			die "URLhandler error: Unable to unset type $type\n";
119	williamc	1.4	}
120	williamc	1.10	# remove the stack if its empty
121			if ( $#{$self->{basestack}{$type}} == -1 ) {
122			delete $self->{basestack}{$type};
123			}
124	williamc	1.1	}
125
126	williamc	1.9	sub currentbase {
127	williamc	1.1	my $self=shift;
128			my $type=shift;
129	williamc	1.9	my $rv;
130	williamc	1.1
131	williamc	1.9	if ( exists $self->{basestack}{$type} ) {
132	williamc	1.10	$rv=${$self->{basestack}{$type}}[$#{$self->{basestack}{$type}}];
133	williamc	1.1	}
134			else {
135	williamc	1.15	$rv=undef;
136	williamc	1.1	}
137	williamc	1.9	return $rv;
138	williamc	1.1	}
139
140	williamc	1.9	sub checktype($type) {
141	williamc	1.1	my $self=shift;
142	williamc	1.9	my $type=shift;
143	williamc	1.1
144	williamc	1.9	# Check type is supported
145	williamc	1.2	if ( ! exists $self->{urlmodules}{$type} ) {
146	williamc	1.9	die "URLhandler error: Unsupported type $type\n";
147	williamc	1.1	}
148			}
149
150	williamc	1.9	sub _typehandler {
151	williamc	1.7	my $self=shift;
152	williamc	1.8	my $type=shift;
153	williamc	1.7
154	williamc	1.9	$self->checktype($type);
155	williamc	1.7
156	williamc	1.9	# instantiate only if it dosnt already exist;
157	williamc	1.10	if ( exists $self->{'urlobjs'}{$type} ) {
158			$self->{'urlobjs'}{$type};
159			}
160			else {
161			$self->{'urlobjs'}{$type}=$self->{urlmodules}{$type}->new();
162			}
163	williamc	1.1	}