Review the communication protocol.

Based on issue #1 it was found out that different servers use different ways
to pass the return status (an HTTP code vs. an application string in the
HTTP body).  In order to unify the handling, the client relies solely on
HTTP codes now. In particular the client doesn't expect any more a string
returned by the server (see the --expect option).

The basics of the protocol are described in the documentation.

The change also introduces the Perl LWP library to handle HTTP messaging and
doesn't require any external commands for that. Some command line options
become superfluous with the change and removed.

Author: kouril

bin/pakiti-client

@@ -17,13 +17,14 @@ use File::Temp qw(tempdir);
 use FindBin qw($Bin $Script);
 use Getopt::Long qw(GetOptions);
 use Pod::Usage qw(pod2usage);
+use LWP::UserAgent ();
 
 #
 # constants
 #
 
 use constant COMMANDS => qw(
-    curl dpkg-query hostname lsb_release openssl pkg rpm svmon uname wget
+    dpkg-query hostname lsb_release openssl pkg rpm svmon uname
 );
 
 use constant PROTOCOL_VERSION => "5";
@@ -373,24 +374,8 @@ sub encrypt_report ($) {
 
 sub send_report ($) {
     my($report) = @_;
-    my($data, @command, $output, $url, @pairs);
+    my($response, $url, @pairs, $ua);
 
-    $TempDir ||= tempdir(CLEANUP => 1);
-    $data = "$TempDir/data";
-    write_file($data, $report);
-    if ($Option{curl}) {
-        @command = ($Option{curl});
-        push(@command, qw(-q --silent -X POST));
-        push(@command, qw(--include --show-error)) if $Option{debug};
-        push(@command, "--data-binary", "\@" . $data);
-    } elsif ($Option{wget}) {
-        @command = ($Option{wget});
-        push(@command, qw(--tries=1 --output-document=-));
-        push(@command, qw(--server-response)) if $Option{debug};
-        push(@command, "--post-file", $data);
-    } else {
-        die("$Script: cannot send to $Option{url}: curl/wget not installed\n");
-    }
     # The caller may specify additional information that doesn't describe the
     # actual patch state but may be useful for the processing. Options recognized
     # as such are sent in the query string.
@@ -402,15 +387,15 @@ sub send_report ($) {
 
     $url = "$Option{url}";
     $url = $url . '?' . join('&', @pairs) if @pairs;
-    ## no critic 'InputOutput::ProhibitBacktickOperators'
-    $output = qx(@command "$url" 2>&1);
-    if ($output =~ /$Option{expect}$/ and $? == 0) {
-        print(STDERR "report successfully sent\n") if -t STDERR;
-        print $output if $output;
-        return;
-    }
-    warn($output) if $output;
-    die("$Script: failed to send data using $command[0]\n");
+
+    $ua = LWP::UserAgent->new;
+    push @{$ua->requests_redirectable}, 'POST';
+
+    $response = $ua->post($url, Content => $report);
+    $response->is_success or die($response->status_line);
+
+    print(STDERR "report successfully sent\n") if -t STDERR;
+    print $response->decoded_content;
 }
 
 #
@@ -459,9 +444,7 @@ sub init () {
     $| = 1;
     %spec = (
         "config"   => "|conf=s",
-        "debug"    => "|d",
         "encrypt"  => "=s",
-        "expect"   => "=s",
         "help"     => "|h|?",
         "host"     => "=s",
         "input"    => "|i=s",
@@ -494,11 +477,8 @@ sub init () {
     foreach my $name (COMMANDS()) {
         $Option{$name} = which($name) unless defined($Option{$name});
     }
-    $Option{expect} = "OK" unless defined($Option{expect});
     die("$Script: option --encrypt requires openssl\n")
         if $Option{encrypt} and not $Option{openssl};
-    die("$Script: option --url requires curl or wget\n")
-        if $Option{url} and not $Option{curl} and not $Option{wget};
 }
 
 #
@@ -611,14 +591,6 @@ with (using bash):
 
 use this configuration file before processing the command line parameters
 
-=item B<--curl> I<PATH>
-
-set the path of the C<curl> command to use
-
-=item B<--debug>, B<-d>
-
-enable debug mode
-
 =item B<--dpkg-query> I<PATH>
 
 set the path of the C<dpkg-query> command to use
@@ -629,11 +601,6 @@ use this certificate to encrypt the report; the value can either be the path
 of the file containing the certificate or the certificate itself as multi-line
 ASCII armored contents
 
-=item B<--expect> I<STRING>
-
-set the response string to expect from the server in case of success
-(default: C<OK>)
-
 =item B<--help>, B<-h>, B<-?>
 
 show some help
@@ -712,10 +679,6 @@ set the path of the C<uname> command to use
 
 send the prepared report to the collecting server at the given URL
 
-=item B<--wget> I<PATH>
-
-set the path of the C<wget> command to use
-
 =back
 
 =head1 CONFIGURATION FILE
@@ -777,6 +740,20 @@ A I<package line> contains the package name, a tab character (0x09), the package
 full version, another tab and the package architecture. For C<rpm> based systems,
 the full version is in fact I<EPOCH>:I<VERSION>:I<RELEASE>.
 
+=head1 PROTOCOL
+
+The messages are sent using the HTTP protocol and the POST method. The
+messages are sent over an TLS-protected channel unless the report is sent as
+an encrypted blob, in which case a plain HTTP connection is recommended to
+use. Messages containing the encrypted blob are label using the
+application/octet-stream mime type. The server uses HTTP codes to signal the
+status of delivery. Servers may return human-readable information
+in the body of HTTP response, which provides additional details about the
+processing.
+
+The client can use query string attributes to pass additional parameters
+important for the processing.
+
 =head1 AUTHOR
 
 Lionel Cons L<http://cern.ch/lionel.cons>

debian/control

@@ -9,7 +9,7 @@ Homepage: https://github.com/CESNET/pakiti3
 
 Package: pakiti-client
 Architecture: all
-Depends: ${misc:Depends}, curl, openssl, perl
+Depends: ${misc:Depends}, openssl, perl, liblwp-protocol-https-perl
 Description: Patch Status Monitoring Tool
  Pakiti provides a monitoring mechanism to check the patching status of
  Linux systems.

pakiti.spec

@@ -9,6 +9,7 @@ Source0:	%{url}/archive/v%{version}.tar.gz
 BuildRoot:	%(mktemp -ud %{_tmppath}/%{name}-%{version}-%{release}-XXXXXX)
 BuildArch:	noarch
 BuildRequires:	perl
+Requires:	openssl perl perl-LWP-Protocol-https
 
 %description
 Pakiti provides a monitoring mechanism to check the patching status of