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Diffstat (limited to 'Master/tlpkg/tlperl/lib/HTTP/Headers.pm')
-rw-r--r-- | Master/tlpkg/tlperl/lib/HTTP/Headers.pm | 849 |
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diff --git a/Master/tlpkg/tlperl/lib/HTTP/Headers.pm b/Master/tlpkg/tlperl/lib/HTTP/Headers.pm new file mode 100644 index 00000000000..1e9198cd3c7 --- /dev/null +++ b/Master/tlpkg/tlperl/lib/HTTP/Headers.pm @@ -0,0 +1,849 @@ +package HTTP::Headers; + +use strict; +use Carp (); + +use vars qw($VERSION $TRANSLATE_UNDERSCORE); +$VERSION = "5.835"; + +# The $TRANSLATE_UNDERSCORE variable controls whether '_' can be used +# as a replacement for '-' in header field names. +$TRANSLATE_UNDERSCORE = 1 unless defined $TRANSLATE_UNDERSCORE; + +# "Good Practice" order of HTTP message headers: +# - General-Headers +# - Request-Headers +# - Response-Headers +# - Entity-Headers + +my @general_headers = qw( + Cache-Control Connection Date Pragma Trailer Transfer-Encoding Upgrade + Via Warning +); + +my @request_headers = qw( + Accept Accept-Charset Accept-Encoding Accept-Language + Authorization Expect From Host + If-Match If-Modified-Since If-None-Match If-Range If-Unmodified-Since + Max-Forwards Proxy-Authorization Range Referer TE User-Agent +); + +my @response_headers = qw( + Accept-Ranges Age ETag Location Proxy-Authenticate Retry-After Server + Vary WWW-Authenticate +); + +my @entity_headers = qw( + Allow Content-Encoding Content-Language Content-Length Content-Location + Content-MD5 Content-Range Content-Type Expires Last-Modified +); + +my %entity_header = map { lc($_) => 1 } @entity_headers; + +my @header_order = ( + @general_headers, + @request_headers, + @response_headers, + @entity_headers, +); + +# Make alternative representations of @header_order. This is used +# for sorting and case matching. +my %header_order; +my %standard_case; + +{ + my $i = 0; + for (@header_order) { + my $lc = lc $_; + $header_order{$lc} = ++$i; + $standard_case{$lc} = $_; + } +} + + + +sub new +{ + my($class) = shift; + my $self = bless {}, $class; + $self->header(@_) if @_; # set up initial headers + $self; +} + + +sub header +{ + my $self = shift; + Carp::croak('Usage: $h->header($field, ...)') unless @_; + my(@old); + my %seen; + while (@_) { + my $field = shift; + my $op = @_ ? ($seen{lc($field)}++ ? 'PUSH' : 'SET') : 'GET'; + @old = $self->_header($field, shift, $op); + } + return @old if wantarray; + return $old[0] if @old <= 1; + join(", ", @old); +} + +sub clear +{ + my $self = shift; + %$self = (); +} + + +sub push_header +{ + my $self = shift; + return $self->_header(@_, 'PUSH_H') if @_ == 2; + while (@_) { + $self->_header(splice(@_, 0, 2), 'PUSH_H'); + } +} + + +sub init_header +{ + Carp::croak('Usage: $h->init_header($field, $val)') if @_ != 3; + shift->_header(@_, 'INIT'); +} + + +sub remove_header +{ + my($self, @fields) = @_; + my $field; + my @values; + foreach $field (@fields) { + $field =~ tr/_/-/ if $field !~ /^:/ && $TRANSLATE_UNDERSCORE; + my $v = delete $self->{lc $field}; + push(@values, ref($v) eq 'ARRAY' ? @$v : $v) if defined $v; + } + return @values; +} + +sub remove_content_headers +{ + my $self = shift; + unless (defined(wantarray)) { + # fast branch that does not create return object + delete @$self{grep $entity_header{$_} || /^content-/, keys %$self}; + return; + } + + my $c = ref($self)->new; + for my $f (grep $entity_header{$_} || /^content-/, keys %$self) { + $c->{$f} = delete $self->{$f}; + } + $c; +} + + +sub _header +{ + my($self, $field, $val, $op) = @_; + + unless ($field =~ /^:/) { + $field =~ tr/_/-/ if $TRANSLATE_UNDERSCORE; + my $old = $field; + $field = lc $field; + unless(defined $standard_case{$field}) { + # generate a %standard_case entry for this field + $old =~ s/\b(\w)/\u$1/g; + $standard_case{$field} = $old; + } + } + + $op ||= defined($val) ? 'SET' : 'GET'; + if ($op eq 'PUSH_H') { + # Like PUSH but where we don't care about the return value + if (exists $self->{$field}) { + my $h = $self->{$field}; + if (ref($h) eq 'ARRAY') { + push(@$h, ref($val) eq "ARRAY" ? @$val : $val); + } + else { + $self->{$field} = [$h, ref($val) eq "ARRAY" ? @$val : $val] + } + return; + } + $self->{$field} = $val; + return; + } + + my $h = $self->{$field}; + my @old = ref($h) eq 'ARRAY' ? @$h : (defined($h) ? ($h) : ()); + + unless ($op eq 'GET' || ($op eq 'INIT' && @old)) { + if (defined($val)) { + my @new = ($op eq 'PUSH') ? @old : (); + if (ref($val) ne 'ARRAY') { + push(@new, $val); + } + else { + push(@new, @$val); + } + $self->{$field} = @new > 1 ? \@new : $new[0]; + } + elsif ($op ne 'PUSH') { + delete $self->{$field}; + } + } + @old; +} + + +sub _sorted_field_names +{ + my $self = shift; + return [ sort { + ($header_order{$a} || 999) <=> ($header_order{$b} || 999) || + $a cmp $b + } keys %$self ]; +} + + +sub header_field_names { + my $self = shift; + return map $standard_case{$_} || $_, @{ $self->_sorted_field_names }, + if wantarray; + return keys %$self; +} + + +sub scan +{ + my($self, $sub) = @_; + my $key; + for $key (@{ $self->_sorted_field_names }) { + next if substr($key, 0, 1) eq '_'; + my $vals = $self->{$key}; + if (ref($vals) eq 'ARRAY') { + my $val; + for $val (@$vals) { + $sub->($standard_case{$key} || $key, $val); + } + } + else { + $sub->($standard_case{$key} || $key, $vals); + } + } +} + + +sub as_string +{ + my($self, $endl) = @_; + $endl = "\n" unless defined $endl; + + my @result = (); + for my $key (@{ $self->_sorted_field_names }) { + next if index($key, '_') == 0; + my $vals = $self->{$key}; + if ( ref($vals) eq 'ARRAY' ) { + for my $val (@$vals) { + my $field = $standard_case{$key} || $key; + $field =~ s/^://; + if ( index($val, "\n") >= 0 ) { + $val = _process_newline($val, $endl); + } + push @result, $field . ': ' . $val; + } + } + else { + my $field = $standard_case{$key} || $key; + $field =~ s/^://; + if ( index($vals, "\n") >= 0 ) { + $vals = _process_newline($vals, $endl); + } + push @result, $field . ': ' . $vals; + } + } + + join($endl, @result, ''); +} + +sub _process_newline { + local $_ = shift; + my $endl = shift; + # must handle header values with embedded newlines with care + s/\s+$//; # trailing newlines and space must go + s/\n(\x0d?\n)+/\n/g; # no empty lines + s/\n([^\040\t])/\n $1/g; # intial space for continuation + s/\n/$endl/g; # substitute with requested line ending + $_; +} + + + +if (eval { require Storable; 1 }) { + *clone = \&Storable::dclone; +} else { + *clone = sub { + my $self = shift; + my $clone = HTTP::Headers->new; + $self->scan(sub { $clone->push_header(@_);} ); + $clone; + }; +} + + +sub _date_header +{ + require HTTP::Date; + my($self, $header, $time) = @_; + my($old) = $self->_header($header); + if (defined $time) { + $self->_header($header, HTTP::Date::time2str($time)); + } + $old =~ s/;.*// if defined($old); + HTTP::Date::str2time($old); +} + + +sub date { shift->_date_header('Date', @_); } +sub expires { shift->_date_header('Expires', @_); } +sub if_modified_since { shift->_date_header('If-Modified-Since', @_); } +sub if_unmodified_since { shift->_date_header('If-Unmodified-Since', @_); } +sub last_modified { shift->_date_header('Last-Modified', @_); } + +# This is used as a private LWP extension. The Client-Date header is +# added as a timestamp to a response when it has been received. +sub client_date { shift->_date_header('Client-Date', @_); } + +# The retry_after field is dual format (can also be a expressed as +# number of seconds from now), so we don't provide an easy way to +# access it until we have know how both these interfaces can be +# addressed. One possibility is to return a negative value for +# relative seconds and a positive value for epoch based time values. +#sub retry_after { shift->_date_header('Retry-After', @_); } + +sub content_type { + my $self = shift; + my $ct = $self->{'content-type'}; + $self->{'content-type'} = shift if @_; + $ct = $ct->[0] if ref($ct) eq 'ARRAY'; + return '' unless defined($ct) && length($ct); + my @ct = split(/;\s*/, $ct, 2); + for ($ct[0]) { + s/\s+//g; + $_ = lc($_); + } + wantarray ? @ct : $ct[0]; +} + +sub content_type_charset { + my $self = shift; + require HTTP::Headers::Util; + my $h = $self->{'content-type'}; + $h = $h->[0] if ref($h); + $h = "" unless defined $h; + my @v = HTTP::Headers::Util::split_header_words($h); + if (@v) { + my($ct, undef, %ct_param) = @{$v[0]}; + my $charset = $ct_param{charset}; + if ($ct) { + $ct = lc($ct); + $ct =~ s/\s+//; + } + if ($charset) { + $charset = uc($charset); + $charset =~ s/^\s+//; $charset =~ s/\s+\z//; + undef($charset) if $charset eq ""; + } + return $ct, $charset if wantarray; + return $charset; + } + return undef, undef if wantarray; + return undef; +} + +sub content_is_text { + my $self = shift; + return $self->content_type =~ m,^text/,; +} + +sub content_is_html { + my $self = shift; + return $self->content_type eq 'text/html' || $self->content_is_xhtml; +} + +sub content_is_xhtml { + my $ct = shift->content_type; + return $ct eq "application/xhtml+xml" || + $ct eq "application/vnd.wap.xhtml+xml"; +} + +sub content_is_xml { + my $ct = shift->content_type; + return 1 if $ct eq "text/xml"; + return 1 if $ct eq "application/xml"; + return 1 if $ct =~ /\+xml$/; + return 0; +} + +sub referer { + my $self = shift; + if (@_ && $_[0] =~ /#/) { + # Strip fragment per RFC 2616, section 14.36. + my $uri = shift; + if (ref($uri)) { + $uri = $uri->clone; + $uri->fragment(undef); + } + else { + $uri =~ s/\#.*//; + } + unshift @_, $uri; + } + ($self->_header('Referer', @_))[0]; +} +*referrer = \&referer; # on tchrist's request + +sub title { (shift->_header('Title', @_))[0] } +sub content_encoding { (shift->_header('Content-Encoding', @_))[0] } +sub content_language { (shift->_header('Content-Language', @_))[0] } +sub content_length { (shift->_header('Content-Length', @_))[0] } + +sub user_agent { (shift->_header('User-Agent', @_))[0] } +sub server { (shift->_header('Server', @_))[0] } + +sub from { (shift->_header('From', @_))[0] } +sub warning { (shift->_header('Warning', @_))[0] } + +sub www_authenticate { (shift->_header('WWW-Authenticate', @_))[0] } +sub authorization { (shift->_header('Authorization', @_))[0] } + +sub proxy_authenticate { (shift->_header('Proxy-Authenticate', @_))[0] } +sub proxy_authorization { (shift->_header('Proxy-Authorization', @_))[0] } + +sub authorization_basic { shift->_basic_auth("Authorization", @_) } +sub proxy_authorization_basic { shift->_basic_auth("Proxy-Authorization", @_) } + +sub _basic_auth { + require MIME::Base64; + my($self, $h, $user, $passwd) = @_; + my($old) = $self->_header($h); + if (defined $user) { + Carp::croak("Basic authorization user name can't contain ':'") + if $user =~ /:/; + $passwd = '' unless defined $passwd; + $self->_header($h => 'Basic ' . + MIME::Base64::encode("$user:$passwd", '')); + } + if (defined $old && $old =~ s/^\s*Basic\s+//) { + my $val = MIME::Base64::decode($old); + return $val unless wantarray; + return split(/:/, $val, 2); + } + return; +} + + +1; + +__END__ + +=head1 NAME + +HTTP::Headers - Class encapsulating HTTP Message headers + +=head1 SYNOPSIS + + require HTTP::Headers; + $h = HTTP::Headers->new; + + $h->header('Content-Type' => 'text/plain'); # set + $ct = $h->header('Content-Type'); # get + $h->remove_header('Content-Type'); # delete + +=head1 DESCRIPTION + +The C<HTTP::Headers> class encapsulates HTTP-style message headers. +The headers consist of attribute-value pairs also called fields, which +may be repeated, and which are printed in a particular order. The +field names are cases insensitive. + +Instances of this class are usually created as member variables of the +C<HTTP::Request> and C<HTTP::Response> classes, internal to the +library. + +The following methods are available: + +=over 4 + +=item $h = HTTP::Headers->new + +Constructs a new C<HTTP::Headers> object. You might pass some initial +attribute-value pairs as parameters to the constructor. I<E.g.>: + + $h = HTTP::Headers->new( + Date => 'Thu, 03 Feb 1994 00:00:00 GMT', + Content_Type => 'text/html; version=3.2', + Content_Base => 'http://www.perl.org/'); + +The constructor arguments are passed to the C<header> method which is +described below. + +=item $h->clone + +Returns a copy of this C<HTTP::Headers> object. + +=item $h->header( $field ) + +=item $h->header( $field => $value ) + +=item $h->header( $f1 => $v1, $f2 => $v2, ... ) + +Get or set the value of one or more header fields. The header field +name ($field) is not case sensitive. To make the life easier for perl +users who wants to avoid quoting before the => operator, you can use +'_' as a replacement for '-' in header names. + +The header() method accepts multiple ($field => $value) pairs, which +means that you can update several fields with a single invocation. + +The $value argument may be a plain string or a reference to an array +of strings for a multi-valued field. If the $value is provided as +C<undef> then the field is removed. If the $value is not given, then +that header field will remain unchanged. + +The old value (or values) of the last of the header fields is returned. +If no such field exists C<undef> will be returned. + +A multi-valued field will be returned as separate values in list +context and will be concatenated with ", " as separator in scalar +context. The HTTP spec (RFC 2616) promise that joining multiple +values in this way will not change the semantic of a header field, but +in practice there are cases like old-style Netscape cookies (see +L<HTTP::Cookies>) where "," is used as part of the syntax of a single +field value. + +Examples: + + $header->header(MIME_Version => '1.0', + User_Agent => 'My-Web-Client/0.01'); + $header->header(Accept => "text/html, text/plain, image/*"); + $header->header(Accept => [qw(text/html text/plain image/*)]); + @accepts = $header->header('Accept'); # get multiple values + $accepts = $header->header('Accept'); # get values as a single string + +=item $h->push_header( $field => $value ) + +=item $h->push_header( $f1 => $v1, $f2 => $v2, ... ) + +Add a new field value for the specified header field. Previous values +for the same field are retained. + +As for the header() method, the field name ($field) is not case +sensitive and '_' can be used as a replacement for '-'. + +The $value argument may be a scalar or a reference to a list of +scalars. + + $header->push_header(Accept => 'image/jpeg'); + $header->push_header(Accept => [map "image/$_", qw(gif png tiff)]); + +=item $h->init_header( $field => $value ) + +Set the specified header to the given value, but only if no previous +value for that field is set. + +The header field name ($field) is not case sensitive and '_' +can be used as a replacement for '-'. + +The $value argument may be a scalar or a reference to a list of +scalars. + +=item $h->remove_header( $field, ... ) + +This function removes the header fields with the specified names. + +The header field names ($field) are not case sensitive and '_' +can be used as a replacement for '-'. + +The return value is the values of the fields removed. In scalar +context the number of fields removed is returned. + +Note that if you pass in multiple field names then it is generally not +possible to tell which of the returned values belonged to which field. + +=item $h->remove_content_headers + +This will remove all the header fields used to describe the content of +a message. All header field names prefixed with C<Content-> fall +into this category, as well as C<Allow>, C<Expires> and +C<Last-Modified>. RFC 2616 denotes these fields as I<Entity Header +Fields>. + +The return value is a new C<HTTP::Headers> object that contains the +removed headers only. + +=item $h->clear + +This will remove all header fields. + +=item $h->header_field_names + +Returns the list of distinct names for the fields present in the +header. The field names have case as suggested by HTTP spec, and the +names are returned in the recommended "Good Practice" order. + +In scalar context return the number of distinct field names. + +=item $h->scan( \&process_header_field ) + +Apply a subroutine to each header field in turn. The callback routine +is called with two parameters; the name of the field and a single +value (a string). If a header field is multi-valued, then the +routine is called once for each value. The field name passed to the +callback routine has case as suggested by HTTP spec, and the headers +will be visited in the recommended "Good Practice" order. + +Any return values of the callback routine are ignored. The loop can +be broken by raising an exception (C<die>), but the caller of scan() +would have to trap the exception itself. + +=item $h->as_string + +=item $h->as_string( $eol ) + +Return the header fields as a formatted MIME header. Since it +internally uses the C<scan> method to build the string, the result +will use case as suggested by HTTP spec, and it will follow +recommended "Good Practice" of ordering the header fields. Long header +values are not folded. + +The optional $eol parameter specifies the line ending sequence to +use. The default is "\n". Embedded "\n" characters in header field +values will be substituted with this line ending sequence. + +=back + +=head1 CONVENIENCE METHODS + +The most frequently used headers can also be accessed through the +following convenience methods. Most of these methods can both be used to read +and to set the value of a header. The header value is set if you pass +an argument to the method. The old header value is always returned. +If the given header did not exist then C<undef> is returned. + +Methods that deal with dates/times always convert their value to system +time (seconds since Jan 1, 1970) and they also expect this kind of +value when the header value is set. + +=over 4 + +=item $h->date + +This header represents the date and time at which the message was +originated. I<E.g.>: + + $h->date(time); # set current date + +=item $h->expires + +This header gives the date and time after which the entity should be +considered stale. + +=item $h->if_modified_since + +=item $h->if_unmodified_since + +These header fields are used to make a request conditional. If the requested +resource has (or has not) been modified since the time specified in this field, +then the server will return a C<304 Not Modified> response instead of +the document itself. + +=item $h->last_modified + +This header indicates the date and time at which the resource was last +modified. I<E.g.>: + + # check if document is more than 1 hour old + if (my $last_mod = $h->last_modified) { + if ($last_mod < time - 60*60) { + ... + } + } + +=item $h->content_type + +The Content-Type header field indicates the media type of the message +content. I<E.g.>: + + $h->content_type('text/html'); + +The value returned will be converted to lower case, and potential +parameters will be chopped off and returned as a separate value if in +an array context. If there is no such header field, then the empty +string is returned. This makes it safe to do the following: + + if ($h->content_type eq 'text/html') { + # we enter this place even if the real header value happens to + # be 'TEXT/HTML; version=3.0' + ... + } + +=item $h->content_type_charset + +Returns the upper-cased charset specified in the Content-Type header. In list +context return the lower-cased bare content type followed by the upper-cased +charset. Both values will be C<undef> if not specified in the header. + +=item $h->content_is_text + +Returns TRUE if the Content-Type header field indicate that the +content is textual. + +=item $h->content_is_html + +Returns TRUE if the Content-Type header field indicate that the +content is some kind of HTML (including XHTML). This method can't be +used to set Content-Type. + +=item $h->content_is_xhtml + +Returns TRUE if the Content-Type header field indicate that the +content is XHTML. This method can't be used to set Content-Type. + +=item $h->content_is_xml + +Returns TRUE if the Content-Type header field indicate that the +content is XML. This method can't be used to set Content-Type. + +=item $h->content_encoding + +The Content-Encoding header field is used as a modifier to the +media type. When present, its value indicates what additional +encoding mechanism has been applied to the resource. + +=item $h->content_length + +A decimal number indicating the size in bytes of the message content. + +=item $h->content_language + +The natural language(s) of the intended audience for the message +content. The value is one or more language tags as defined by RFC +1766. Eg. "no" for some kind of Norwegian and "en-US" for English the +way it is written in the US. + +=item $h->title + +The title of the document. In libwww-perl this header will be +initialized automatically from the E<lt>TITLE>...E<lt>/TITLE> element +of HTML documents. I<This header is no longer part of the HTTP +standard.> + +=item $h->user_agent + +This header field is used in request messages and contains information +about the user agent originating the request. I<E.g.>: + + $h->user_agent('Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 6.0)'); + +=item $h->server + +The server header field contains information about the software being +used by the originating server program handling the request. + +=item $h->from + +This header should contain an Internet e-mail address for the human +user who controls the requesting user agent. The address should be +machine-usable, as defined by RFC822. E.g.: + + $h->from('King Kong <king@kong.com>'); + +I<This header is no longer part of the HTTP standard.> + +=item $h->referer + +Used to specify the address (URI) of the document from which the +requested resource address was obtained. + +The "Free On-line Dictionary of Computing" as this to say about the +word I<referer>: + + <World-Wide Web> A misspelling of "referrer" which + somehow made it into the {HTTP} standard. A given {web + page}'s referer (sic) is the {URL} of whatever web page + contains the link that the user followed to the current + page. Most browsers pass this information as part of a + request. + + (1998-10-19) + +By popular demand C<referrer> exists as an alias for this method so you +can avoid this misspelling in your programs and still send the right +thing on the wire. + +When setting the referrer, this method removes the fragment from the +given URI if it is present, as mandated by RFC2616. Note that +the removal does I<not> happen automatically if using the header(), +push_header() or init_header() methods to set the referrer. + +=item $h->www_authenticate + +This header must be included as part of a C<401 Unauthorized> response. +The field value consist of a challenge that indicates the +authentication scheme and parameters applicable to the requested URI. + +=item $h->proxy_authenticate + +This header must be included in a C<407 Proxy Authentication Required> +response. + +=item $h->authorization + +=item $h->proxy_authorization + +A user agent that wishes to authenticate itself with a server or a +proxy, may do so by including these headers. + +=item $h->authorization_basic + +This method is used to get or set an authorization header that use the +"Basic Authentication Scheme". In array context it will return two +values; the user name and the password. In scalar context it will +return I<"uname:password"> as a single string value. + +When used to set the header value, it expects two arguments. I<E.g.>: + + $h->authorization_basic($uname, $password); + +The method will croak if the $uname contains a colon ':'. + +=item $h->proxy_authorization_basic + +Same as authorization_basic() but will set the "Proxy-Authorization" +header instead. + +=back + +=head1 NON-CANONICALIZED FIELD NAMES + +The header field name spelling is normally canonicalized including the +'_' to '-' translation. There are some application where this is not +appropriate. Prefixing field names with ':' allow you to force a +specific spelling. For example if you really want a header field name +to show up as C<foo_bar> instead of "Foo-Bar", you might set it like +this: + + $h->header(":foo_bar" => 1); + +These field names are returned with the ':' intact for +$h->header_field_names and the $h->scan callback, but the colons do +not show in $h->as_string. + +=head1 COPYRIGHT + +Copyright 1995-2005 Gisle Aas. + +This library is free software; you can redistribute it and/or +modify it under the same terms as Perl itself. + |