Bug 14251: Allow use of CSS in discharge letter

The discharge feature relies PDF::FromHTML which explicitly doesn't
handle CSS [1].

This patch makes it use the `weasyprint` command-line tool to generate
the PDF. This tool handles CSS correctly.

To test:
1. Install weasyprint:
   $ apt install weasyprint
2. Add some style to your DISCHARGE letter. I used:
<<today>>
<h1>Discharge confirmation</h1>
<p style="background-color: yellow;"><<branches.branchname>> certifies that the following borrower:<br>
<<borrowers.firstname>> <<borrowers.surname>> (cardnumber: <<borrowers.cardnumber>>)<br>
has returned all items.</p>
3. Have some non-latin chars on the patron name. I picked 'Henry
   Acevedo' and added 'Δοκιμή' as picked from bug 23589. Only to check no
   regressions.
4. Enable the 'UseDischarge' syspref
5. Go to Henry's detail page
6. Choose More > Discharge and Generate the discharge
=> SUCCESS:
   - Style is applied to the PDF
   - Greek characters are displayed correctly
7. Run the tests:
   $ kshell
  k$ prove -v t/db_dependent/Patron/Borrower_Discharge.t
=> SUCCESS: The rewritten tests pass!
8. Remove weasyprint:
   $ apt remove weasyprint
9. Repeat 7
=> SUCCESS: Tests pass, relevant test is skipped because of missing
            weasyprint
10. Sign off :-D

[1] https://metacpan.org/pod/PDF::FromHTML#CAVEATS

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>

diff --git a/Koha/Patron/Discharge.pm b/Koha/Patron/Discharge.pm
index 76e04e8..f86d4d7 100644 (file)
--- a/Koha/Patron/Discharge.pm
+++ b/Koha/Patron/Discharge.pm
@@ -3,6 +3,7 @@ package Koha::Patron::Discharge;
 use Modern::Perl;
 use CGI;
 use File::Temp qw( tmpnam );
+use IPC::Cmd;
 use Carp qw( carp );
 
 use C4::Templates qw ( gettemplate );
@@ -128,40 +129,27 @@ sub generate_as_pdf {
     my $html_path = tmpnam() . '.html';
     my $pdf_path = tmpnam() . '.pdf';
     my $html_content = $tmpl->output;
+
+    # export to HTML
     open my $html_fh, '>:encoding(utf8)', $html_path;
     say $html_fh $html_content;
     close $html_fh;
-    my $output = eval { require PDF::FromHTML; return; } || $@;
-    if ($output && $params->{testing}) {
-        carp $output;
-        $pdf_path = undef;
-    }
-    elsif ($output) {
-        die $output;
+
+    if ( IPC::Cmd::can_run('weasyprint') ) {
+        my( $success, $error_message, $full_buf, $stdout_buf, $stderr_buf ) =
+            IPC::Cmd::run( command => "weasyprint $html_path $pdf_path", verbose => 0 );
+
+        map {warn $_} @$stderr_buf
+          if $stderr_buf and scalar @$stderr_buf;
+
+        unless ( $success ) {
+            warn $error_message;
+            $pdf_path = undef;
+        }
     }
     else {
-        my $pdf = PDF::FromHTML->new( encoding => 'utf-8' );
-        $pdf->load_file( $html_path );
-
-        my $ttf = C4::Context->config('ttf');
-        if ( $ttf  && exists $ttf->{font} ) {
-
-            my $type2path;
-            foreach my $font ( @{ $ttf->{font} } ) {
-                    $type2path->{ $font->{type} } = $font->{content};
-            }
-
-            $pdf->convert(
-                FontBold          => $type2path->{'HB'} || 'HelveticaBold',
-                FontOblique       => $type2path->{'HO'} || 'HelveticaOblique',
-                FontBoldOblique   => $type2path->{'HBO'}|| 'HelveticaBoldOblique',
-                FontUnicode       => $type2path->{'H'}  || 'Helvetica',
-                Font              => $type2path->{'H'}  || 'Helvetica',
-            );
-        } else {
-            $pdf->convert();
-        }
-        $pdf->write_file( $pdf_path );
+        warn "weasyprint not found!";
+        $pdf_path = undef;
     }
 
     return $pdf_path;

diff --git a/t/db_dependent/Patron/Borrower_Discharge.t b/t/db_dependent/Patron/Borrower_Discharge.t
index 8c74219..2145339 100755 (executable)
--- a/t/db_dependent/Patron/Borrower_Discharge.t
+++ b/t/db_dependent/Patron/Borrower_Discharge.t
@@ -15,8 +15,13 @@
 # with Koha; if not, see <http://www.gnu.org/licenses>.
 
 use Modern::Perl;
-use Test::More tests => 19;
+
+use Test::More tests => 23;
+
+use Test::MockModule;
 use Test::Warn;
+
+use IPC::Cmd qw(can_run);
 use MARC::Record;
 
 use C4::Circulation qw( AddIssue AddReturn );
@@ -114,18 +119,36 @@ is(scalar( Koha::Patron::Discharge::get_pendings ), 1, 'There is a pending disch
 Koha::Patron::Discharge::discharge( { borrowernumber => $patron->{borrowernumber} } );
 is_deeply( [ Koha::Patron::Discharge::get_pendings ], [], 'There is no pending discharge request (second time)');
 
-# Check if PDF::FromHTML is installed.
-my $check = eval { require PDF::FromHTML; };
+SKIP: {
+    skip "Skipping because weasyprint is not installed",
+        5 unless can_run('weasyprint');
 
-# Tests for if PDF::FromHTML is installed
-if ($check) {
-    isnt( Koha::Patron::Discharge::generate_as_pdf({ borrowernumber => $patron->{borrowernumber} }), undef, "Temporary PDF generated." );
-}
-# Tests for if PDF::FromHTML is not installed
-else {
-    warning_like { Koha::Patron::Discharge::generate_as_pdf({ borrowernumber => $patron->{borrowernumber}, testing => 1 }) }
-          [ qr/Can't locate PDF\/FromHTML.pm in \@INC/ ],
-          "Expected failure because of missing PDF::FromHTML.";
+    isnt(
+        Koha::Patron::Discharge::generate_as_pdf( { borrowernumber => $patron->{borrowernumber} } ),
+        undef,
+        "Temporary PDF generated."
+    );
+
+    my $mocked_ipc = Test::MockModule->new('IPC::Cmd');
+
+    $mocked_ipc->mock( 'run', sub { return 0, 'Some error' } );
+
+    my $result;
+    warning_is
+        { $result = Koha::Patron::Discharge::generate_as_pdf( { borrowernumber => $patron->{borrowernumber} } ); }
+        'Some error',
+        'Failed call to run() prints the generated error';
+
+    is( $result, undef, 'undef returned if failed run' );
+
+    $mocked_ipc->mock( 'can_run', undef );
+
+    warning_is
+        { $result = Koha::Patron::Discharge::generate_as_pdf( { borrowernumber => $patron->{borrowernumber} } ); }
+        'weasyprint not found!',
+        'Expected failure because of missing weasyprint';
+
+    is( $result, undef, 'undef returned if missing weasyprint' );
 }
 
 # FIXME Should be a Koha::Object object