Tests: tests for usage of discarded body. The client_max_body_size limit should be ignored when the request body is already discarded. In HTTP/1.x, this is done by checking the r->discard_body flag when the body is being discarded, and because r->headers_in.content_length_n is 0 when it's already discarded. This, however, does not happen with HTTP/2 and HTTP/3, and therefore "error_page 413" does not work without relaxing the limit. Further, with proxy_pass, r->headers_in.content_length_n is used to determine length of the request body, and therefore is not correct if discarding of the request body isn't yet complete. While discarding the request body, r->headers_in.content_length_n contains the rest of the body to discard (or, in case of chunked request body, the rest of the current chunk to discard). Similarly, the $content_length variable uses r->headers_in.content_length if available, and also incorrect. The $content_length variable is used when proxying with fastcgi_pass, grpc_pass, and uwsgi_pass (scgi_pass uses the value calculated based on the actual request body buffers, and therefore works correctly).

#!/usr/bin/perl

# (C) Sergey Kandaurov
# (C) Nginx, Inc.

# Test for sub_filter inheritance from http context.

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use warnings;
use strict;

use Test::More;

BEGIN { use FindBin; chdir($FindBin::Bin); }

use lib 'lib';
use Test::Nginx;

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select STDERR; $| = 1;
select STDOUT; $| = 1;

my $t = Test::Nginx->new()->has(qw/http sub/);

$t->plan(1)->write_file_expand('nginx.conf', <<'EOF');

%%TEST_GLOBALS%%

daemon off;

events {
}

http {
    %%TEST_GLOBALS_HTTP%%

    sub_filter foo bar;

    server {
        listen       127.0.0.1:8080;
        server_name  localhost;

        location / { }
    }
}

EOF

$t->write_file('foo.html', 'foo');
$t->run();

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like(http_get('/foo.html'), qr/bar/, 'sub_filter inheritance');

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