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# please insert nothing before this line: -*- mode: cperl; cperl-indent-level: 4; cperl-continued-statement-offset: 4; indent-tabs-mode: nil -*-
use strict;
use warnings FATAL => 'all';
use Apache::Test;
use Apache::TestUtil;
use Apache::TestRequest;
plan tests => 12 * 2 + 3;
my $location = "/TestApache__content_length_header";
# 1. because Apache proclaims itself governor of the C-L header via
# the C-L filter (ap_content_length_filter at
# httpd-2.0/server/protocol.c), test whether GET and HEAD behave the
# same wrt C-L under varying circumstances. for the most part GET
# and HEAD should behave exactly the same. however, when Apache
# sees a HEAD request with a C-L header of zero it takes special
# action and removes the C-L header. this is done to protect against
# handlers that called r->header_only (which was ok in 1.3 but is
# not in 2.0). So, GET and HEAD behave the same except when the
# content handler (plus filters) end up sending no content. see
# the lengthy comments in ap_http_header_filter in http_protocol.c.
#
# for more discussion on
# why it is important to get HEAD requests right, see these threads
# from the mod_perl list
# http://marc.theaimsgroup.com/?l=apache-modperl&m=108647669726915&w=2
# http://marc.theaimsgroup.com/?t=109122984600001&r=1&w=2
# as well as this bug report from mozilla, which shows how they
# are using HEAD requests in the wild
# http://bugzilla.mozilla.org/show_bug.cgi?id=245447
foreach my $method (qw(GET HEAD)) {
no strict qw(refs);
{
# if the response handler sends no data, and sets no C-L header,
# the client doesn't get C-L header at all.
#
# in 2.0 GET requests get a C-L of zero, while HEAD requests do
# not due to special processing.
my $uri = $location;
my $res = $method->($uri);
my $cl = 0;
my $head_cl = undef;
ok t_cmp $res->code, 200, "$method $uri code";
ok t_cmp ($res->header('Content-Length'),
$method eq 'GET' ? $cl : $head_cl,
"$method $uri C-L header");
ok t_cmp $res->content, "", "$method $uri content";
}
{
# if the response handler sends no data and sets C-L header,
# the client should receive the set content length. in 2.1
# this is the way it happens. see protocol.c -r1.150 -r1.151
#
# in 2.0 the client doesn't get C-L header for HEAD requests
# due to special processing, and GET requests get a calculated
# C-L of zero.
my $uri = "$location?set_content_length";
my $res = $method->($uri);
my $cl = 0;
my $head_cl;
## 2.2.1, 2.0.56, 2.0.57 were not released
## but we use the versions the changes went into
## to protect against wierd SVN checkout building.
## XXX: I'm starting to think this test is more
## trouble then its worth.
if (have_min_apache_version("2.2.1")) {
$head_cl = 25;
}
elsif (have_min_apache_version("2.2.0")) {
# $head_cl = undef; # avoid warnings
}
elsif (have_min_apache_version("2.0.56")) {
$head_cl = 25;
}
else {
# $head_cl = undef; # avoid warnings
}
ok t_cmp $res->code, 200, "$method $uri code";
ok t_cmp ($res->header('Content-Length'),
$method eq 'GET' ? $cl : $head_cl,
"$method $uri C-L header");
ok t_cmp $res->content, "", "$method $uri content";
}
{
# if the response handler sends data, and sets no C-L header,
# the client doesn't get C-L header.
my $uri = "$location?send_body";
my $res = $method->($uri);
ok t_cmp $res->code, 200, "$method $uri code";
ok t_cmp $res->header('Content-Length'), undef,
"$method $uri C-L header";
my $content = $method eq 'GET' ? 'This is a response string' : '';
ok t_cmp $res->content, $content, "$method $uri content";
}
{
# if the response handler sends data (e.g. one char string), and
# sets C-L header, the client gets the C-L header
my $uri = "$location?send_body+set_content_length";
my $res = $method->($uri);
ok t_cmp $res->code, 200, "$method $uri code";
ok t_cmp $res->header('Content-Length'), 25,
"$method $uri C-L header";
my $content = $method eq 'GET' ? 'This is a response string' : '';
ok t_cmp $res->content, $content, "$method $uri content";
}
}
# 2. even though the spec says that content handlers should send an
# identical response for GET and HEAD requests, some folks try to
# avoid the overhead of generating the response body, which Apache is
# going to discard anyway for HEAD requests. The following discussion
# assumes that we deal with a HEAD request.
#
# When Apache sees EOS and no headers and no response body were sent,
# ap_content_length_filter (httpd-2.0/server/protocol.c) sets C-L to
# 0. Later on ap_http_header_filter
# (httpd-2.0/modules/http/http_protocol.c) removes the C-L header for
# the HEAD requests
#
# the workaround is to force the sending of the response headers,
# before EOS was sent. The simplest solution is to use rflush():
#
# if ($r->header_only) { # HEAD
# $body_len = calculate_body_len();
# $r->set_content_length($body_len);
# $r->rflush;
# }
# else { # GET
# # generate and send the body
# }
#
# now if the handler sets the C-L header it'll be delivered to the
# client unmodified.
{
# if the response handler sends data (e.g. one char string), and
# sets C-L header, the client gets the C-L header
my $uri = "$location?head_no_body+set_content_length";
my $res = HEAD $uri;
ok t_cmp $res->code, 200, "HEAD $uri code";
ok t_cmp $res->header('Content-Length'), 25, "HEAD $uri C-L header";
ok t_cmp $res->content, '', "HEAD $uri content";
}
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