removed compile-time dep on a valid $dbh from C4::Dates

This replaces using the package variable $prefformat directly, and
specifically, doing a call to C4::Context->preference() during
module initialization.  That way, C4::Dates no longer has a
compile-time dependency on having a valid $dbh.

The inspiration for this is making it easier for
zebraqueue_daemon to have code that detects when
the database connection goes down and then try to
reconnect to the DB.

Signed-off-by: Joshua Ferraro <jmf@liblime.com>

diff --git a/C4/Dates.pm b/C4/Dates.pm
index f10582b..040076b 100644 (file)
--- a/C4/Dates.pm
+++ b/C4/Dates.pm
@@ -31,7 +31,14 @@ BEGIN {
        @EXPORT_OK = qw(DHTMLcalendar format_date_in_iso format_date);
 }
 
-my $prefformat = C4::Context->preference('dateformat');
+my $prefformat;
+sub _prefformat {
+    unless (defined $prefformat) {
+        $prefformat = C4::Context->preference('dateformat');
+    }
+    return $prefformat;
+}
+
 # print STDERR " Dates :      \$debug is '$debug'\n";
 # print STDERR " Dates :  \$cgi_debug is '$cgi_debug'\n";
 
@@ -116,7 +123,7 @@ sub new {
 sub init ($;$$) {
        my $self = shift;
        my $dformat;
-       $self->{'dateformat'} = $dformat = (scalar(@_) >= 2) ? $_[1] : $prefformat;
+       $self->{'dateformat'} = $dformat = (scalar(@_) >= 2) ? $_[1] : _prefformat();
        ($format_map{$dformat}) or croak 
                "Invalid date format '$dformat' from " . ((scalar(@_) >= 2) ? 'argument' : 'system preferences');
        $self->{'dmy_arrayref'} = [((@_) ? $self->dmy_map(shift) : localtime )] ;
@@ -125,24 +132,24 @@ sub init ($;$$) {
 }
 sub output ($;$) {
        my $self = shift;
-       my $newformat = (@_) ? _recognize_format(shift) : $prefformat;
+       my $newformat = (@_) ? _recognize_format(shift) : _prefformat();
        return (eval {POSIX::strftime($posix_map{$newformat}, @{$self->{'dmy_arrayref'}})} || undef);
 }
 sub today ($;$) {              # NOTE: sets date value to today (and returns it in the requested or current format)
        my $class = shift;
        $class = ref($class) || $class;
-       my $format = (@_) ? _recognize_format(shift) : $prefformat;
+       my $format = (@_) ? _recognize_format(shift) : _prefformat();
        return $class->new()->output($format);
 }
 sub _recognize_format($) {
        my $incoming = shift;
-       ($incoming eq 'syspref') and return $prefformat;
+       ($incoming eq 'syspref') and return _prefformat();
        (scalar grep (/^$incoming$/, keys %format_map) == 1) or croak "The format you asked for ('$incoming') is unrecognized.";
        return $incoming;
 }
 sub DHTMLcalendar ($;$) {      # interface to posix_map
        my $class = shift;
-       my $format = (@_) ? shift : $prefformat;
+       my $format = (@_) ? shift : _prefformat();
        return $posix_map{$format};     
 }
 sub format {   # get or set dateformat: iso, metric, us, etc.
@@ -155,16 +162,16 @@ sub visual {
        if (@_) {
                return $format_map{ _recognize_format(shift) };
        }
-       $self eq __PACKAGE__ and return $format_map{$prefformat};
-       return $format_map{ eval { $self->{'dateformat'} } || $prefformat} ;
+       $self eq __PACKAGE__ and return $format_map{_prefformat()};
+       return $format_map{ eval { $self->{'dateformat'} } || _prefformat()} ;
 }
 
 # like the functions from the old C4::Date.pm
 sub format_date {
-       return __PACKAGE__ -> new(shift,'iso')->output((@_) ? shift : $prefformat);
+       return __PACKAGE__ -> new(shift,'iso')->output((@_) ? shift : _prefformat());
 }
 sub format_date_in_iso {
-       return __PACKAGE__ -> new(shift,$prefformat)->output('iso');
+       return __PACKAGE__ -> new(shift,_prefformat())->output('iso');
 }
 
 1;
@@ -291,5 +298,16 @@ This kind of check should be centralized somewhere.  Probably not here, though.
 
 Notes: if the date in the db is null or empty, interpret null expiration to mean "never expires".
 
+=head3 _prefformat()
+
+This internal function is used to read the preferred date format
+from the system preference table.  It reads the preference once, 
+then caches it.
+
+This replaces using the package variable $prefformat directly, and
+specifically, doing a call to C4::Context->preference() during
+module initialization.  That way, C4::Dates no longer has a
+compile-time dependency on having a valid $dbh.
+
 =cut