testclient

this gives details of the network programming

#!/usr/local/bin/perl
#
# Netprog spring 98
#
# test client used for grading proxy web servers
# give this perl script the address of the server as a hostname and port number
#
# This client reads a script that contains commands used to test
# project 1 submissions. Supported commands are:
#
# CONNECT        : establish a connection to the proxy server
#                  (forces a close as well)
# SEND string    : send the specified string
# CLOSE          : close the TCP socket the proxy
# READLINE       : read one line from proxy and toss away
# READALL        : read from proxy until EOF (tossing away)
# SAVEALL file   : read from proxy until EOF and save in file
# SAVECONTENT    : skip headers and save content in file
# ECHOLINE       : read one line from proxy and print
# ECHOALL        : read from proxy until EOF and print
# EXPECT file    : read from proxy until EOF and compare to a file
# EXPECTCONTENT file  : read from proxy, until EOF and compare to a file
#                        tosses headers before comparing
# PRINT string   : print the string to STDOUT
# EVAL string   : eval the perl commandprint the string to STDOUT


require 5.002;
use strict;
#use sigtrap;
use Socket;

$SIG{'PIPE'} = 'IGNORE';

my %commands = (
	     "close",1,
	     "connect",1,
	     "echoall",1,
	     "echoline",1,
	     "expect",1,
	     "expectcontent",1,
	     "print",1,
	     "readall",1,
	     "readline",1,
	     "send",1,
	     "saveall",1,
             "savecontent",1,
             "eval",1,
	     "sleep",1);

select STDOUT; $|=1;

# collect command line parameters

my $hostname = shift || die "No host specified!";
my $port = shift || die "No port specified!";
my $script = shift || die "No script specified";
my($command,@tmp,$perlcom);


open(SCRIPT,"$script") || die $!;
# process commands from the script file
while (<SCRIPT>) {
    chomp; ($command,@tmp) = split;
    $command =~ tr/A-Z/a-z/; 
    if ($command =~/^\s*$/) {
	# nothing - skip it
    } elsif ($command =~ /^#.*$/) {
	printf "$_\n";
    } elsif (! $commands{$command}) {
	print("Error - unknown command: $command ($_)\n");
    } else {
	$perlcom = $command . "_handler \"$_\"";
#	printf("Trying $perlcom\n");
	eval $perlcom;
    }
}
close(SCRIPT);

sub close_handler {
    close(PROX);
}

sub sleep_handler {
    local($_)=$_[0];
    s/SLEEP//;
    sleep $_;
}

sub eval_handler {
    local($_)=$_[0];
    s/EVAL//;
#    printf("EVAL $_\n");
    eval $_;
}

sub print_handler {
    local($_)=$_[0];
    s/PRINT\s+//;
    print "$_\n";
#    eval $_;
}



sub connect_handler {
#    printf("CONNECT\n");
    np_connect($hostname,$port);
}


sub echoall_handler {
    while (<PROX>) {
	printf("$_");
    }
    close(PROX);
}

sub readall_handler {
    while (<PROX>) {
    }
    close(PROX);
}


sub echoline_handler {
    $_=<PROX>;
    printf("$_");
}

sub readline_handler {
    $_=<PROX>;
}



# 
sub saveall_handler {
    local($_) = $_[0];
    my($cmd,$file) = split;
    open(F,">$file") || die $!;
    my($len,$buf);

    while (<PROX>) {
	print F $_;
    }
    close(F);
    close(PROX);
}


# savecontent assumes we are seeing the entire reply
# and tosses headers
sub savecontent_handler {
    local($_) = $_[0];
    my($save) = $_;

    $_=<PROX>;           # the reply
    while (($_=<PROX>) && (! /^\r\n/)) {
#	print;
    }
    saveall_handler($save);
}

sub expect_handler {
    local($_) = $_[0];
    my($cmd,$file) = split;
    my($line);
    my($same)=0;
    if (! -f $file) {
	printf("Error - can't find the file: $_[0]\n");
    } else {
	open(F,"$file") || die $!;
	while (($line = <F>) && ($same<10)) {
	    $_=<PROX>;
#	    chomp; s/\r//g;
#	    $line = <F>;
#	    chomp($line); $line =~ s/\r//g;
	    if ( $line ne $_ ) {
		$same++;
		printf("EXPECT error - lines do not match:\n");
		printf("PROXY: $_\n");
		printf("FILE:  $line\n");
	    }
	}
	close(F);
	close(PROX);
	if ($same==0) {
	    printf("EXPECT checks OK\n");
	} elsif ($same>=10) {
	    printf("EXPECT terminating early - too many differences\n");
	}
    }
}

# expectcontent just reads the headers and
# then calls the expect handler
sub expectcontent_handler {
    my($save) = $_[0];
    $_=<PROX>;    # get The reply line
    
    while (($_=<PROX>) && (! /^\r\n/)) {
    }
    expect_handler( $save );
}

# sends a string to the TCP socket
sub send_handler {
    local($_) = $_[0];
    s/SEND //;
    printf PROX "$_";
}


#
# handles the CONNECT command 

sub np_connect {
    my($chost,$cport) = @_;

    # just in case
    close(PROX);           

    # create a socket
    socket(PROX, PF_INET, SOCK_STREAM, getprotobyname('tcp')) or die $!;

    my $addr = gethostbyname($chost);

    # build address of destination
    # Need perl 5.002 to do this 
    my $serv_addr = sockaddr_in($cport,$addr) || die $!;

    # call connect
    connect(PROX,$serv_addr) || die $!;
    select PROX; $|=1;  select STDOUT;
}

sub np_test {
    print(PROX "GET http://localhost/ HTTP/1.0\r\n\r\n");
    while (<PROX>) {
	print "$_\n";
    }
}