Added exception handling

git-svn-id: http://svn.maypole.perl.org/Maypole/trunk@183 48953598-375a-da11-a14b-00016c27c3ee

diff --git a/Changes b/Changes
index ac6493ac28de92eff325fa28351b46cf8b96bd00..30353b9baf7cd6d7b370d80574709237e7b21c9e 100644 (file)
--- a/Changes
+++ b/Changes
@@ -1,13 +1,14 @@
 Revision history for Perl extension Maypole 
 
-1.8   XXX XXX XX XX:XX:XX XXX XXXX
+2.0   XXX XXX XX XX:XX:XX XXX XXXX
     - Added parse_args() (Simon Flack)
     - call additional_data() and authenticate() for plain templates
     - merged Apache2::MVC (mod_perl2 support) into Apache::MVC
-    - added Maypole::Application universal loader
+    - added Maypole::Application universal front-end
     - config parameter handling for Maypole::Model::CDBI
     - $r->{query} is now deprecated, use $r->{params} for GET and POST
     - fixed multiple value handling (Simon Flack)
+    - added exception handling (Simon Flack)
 
 1.7   Sat Jul 17 20:15:26 BST 2004
     - Emergency release - we lost the "use Maypole::Constants" from

diff --git a/lib/Maypole.pm b/lib/Maypole.pm
index b18aac351ac44b21cb3d1ddd71a5021e4c19f35a..4a5a8e79cb82a5a982b150c0c599cf15a2ed74ed 100644 (file)
--- a/lib/Maypole.pm
+++ b/lib/Maypole.pm
@@ -6,9 +6,11 @@ use strict;
 use warnings;
 our $VERSION = "1.8";
 __PACKAGE__->mk_classdata($_) for qw( config init_done view_object );
-__PACKAGE__->mk_accessors ( qw( ar params query objects model_class
-args action template ));
-__PACKAGE__->config({});
+__PACKAGE__->mk_accessors(
+    qw( ar params query objects model_class
+      args action template )
+);
+__PACKAGE__->config( {} );
 __PACKAGE__->init_done(0);
 use Maypole::Constants;
 
@@ -18,36 +20,39 @@ sub setup {
     my $calling_class = shift;
     $calling_class = ref $calling_class if ref $calling_class;
     {
-      no strict 'refs';
-      # Naughty.
-      *{$calling_class."::handler"} = sub { Maypole::handler($calling_class, @_) };
+        no strict 'refs';
+
+        # Naughty.
+        *{ $calling_class . "::handler" } =
+          sub { Maypole::handler( $calling_class, @_ ) };
     }
     my $config = $calling_class->config;
     $config->{model} ||= "Maypole::Model::CDBI";
     $config->{model}->require;
     die "Couldn't load the model class $config->{model}: $@" if $@;
-    $config->{model}->setup_database($config, $calling_class, @_);
-    for my $subclass (@{$config->{classes}}) {
+    $config->{model}->setup_database( $config, $calling_class, @_ );
+    for my $subclass ( @{ $config->{classes} } ) {
         no strict 'refs';
-        unshift @{$subclass."::ISA"}, $config->{model};
+        unshift @{ $subclass . "::ISA" }, $config->{model};
         $config->{model}->adopt($subclass)
-           if $config->{model}->can("adopt");
+          if $config->{model}->can("adopt");
     }
 }
 
 sub init {
-    my $class = shift;
+    my $class  = shift;
     my $config = $class->config;
-    $config->{view}  ||= "Maypole::View::TT";
+    $config->{view} ||= "Maypole::View::TT";
     $config->{view}->require;
     die "Couldn't load the view class $config->{view}: $@" if $@;
-    $config->{display_tables} ||= [ @{$class->config->{tables}} ];
-    $class->view_object($class->config->{view}->new);
+    $config->{display_tables} ||= [ @{ $class->config->{tables} } ];
+    $class->view_object( $class->config->{view}->new );
     $class->init_done(1);
 
 }
 
 sub handler {
+
     # See Maypole::Workflow before trying to understand this.
     my ( $class, $req ) = @_;
     $class->init unless $class->init_done;
@@ -62,77 +67,107 @@ sub handler {
 
 sub handler_guts {
     my $r = shift;
-    $r->model_class($r->config->{model}->class_of($r, $r->{table}));
+    $r->model_class( $r->config->{model}->class_of( $r, $r->{table} ) );
     my $applicable = $r->is_applicable;
-    unless ($applicable == OK) {
+    unless ( $applicable == OK ) {
+
         # It's just a plain template
         delete $r->{model_class};
-        $r->{path} =~ s{/$}{}; # De-absolutify
-        $r->template($r->{path});
+        $r->{path} =~ s{/$}{};    # De-absolutify
+        $r->template( $r->{path} );
     }
+
     # We authenticate every request, needed for proper session management
     my $status = $r->call_authenticate;
-    if ($r->debug and $status != OK and $status != DECLINED) {
-        $r->view_object->error($r,
-            "Got unexpected status $status from calling authentication");
+    if ( $r->debug and $status != OK and $status != DECLINED ) {
+        $r->view_object->error( $r,
+            "Got unexpected status $status from calling authentication" );
     }
     return $status unless $status == OK;
+
     # We run additional_data for every request
     $r->additional_data;
-    if ($applicable == OK) {
-        $r->model_class->process($r);
+    if ( $applicable == OK ) {
+        eval { $r->model_class->process($r) };
+        if ( my $error = $@ ) {
+            $status = $r->call_exception($error);
+            if ( $status != OK ) {
+                warn "caught model error: $error";
+                return $r->debug ? $r->view_object->error( $r, $error ) : ERROR;
+            }
+        }
     }
-    if (!$r->{output}) { # You might want to do it yourself
+    if ( !$r->{output} ) {    # You might want to do it yourself
         return $r->view_object->process($r);
-    } else { return OK; }
+    }
+    else { return OK; }
 }
 
 sub is_applicable {
-    my $self = shift;
+    my $self   = shift;
     my $config = $self->config;
     $config->{ok_tables} ||= $config->{display_tables};
-    $config->{ok_tables} = {map {$_=>1} @{$config->{ok_tables}}}
-       if ref $config->{ok_tables} eq "ARRAY";
+    $config->{ok_tables} = { map { $_ => 1 } @{ $config->{ok_tables} } }
+      if ref $config->{ok_tables} eq "ARRAY";
     warn "We don't have that table ($self->{table})"
-        if $self->debug and not $config->{ok_tables}{$self->{table}};
-    return DECLINED() unless exists $config->{ok_tables}{$self->{table}};
+      if $self->debug
+      and not $config->{ok_tables}{ $self->{table} };
+    return DECLINED() unless exists $config->{ok_tables}{ $self->{table} };
 
     # Does the action method exist?
-    my $cv = $self->model_class->can($self->{action});
-    warn "We don't have that action ($self->{action})" 
-        if $self->debug and not $cv;
+    my $cv = $self->model_class->can( $self->{action} );
+    warn "We don't have that action ($self->{action})"
+      if $self->debug and not $cv;
     return DECLINED() unless $cv;
 
     # Is it exported?
     $self->{method_attribs} = join " ", attributes::get($cv);
-    do { warn "$self->{action} not exported" if $self->debug;
-    return DECLINED() 
-     } unless $self->{method_attribs} =~ /\bExported\b/i;
+    do {
+        warn "$self->{action} not exported" if $self->debug;
+        return DECLINED();
+    } unless $self->{method_attribs} =~ /\bExported\b/i;
     return OK();
 }
 
 sub call_authenticate {
     my $self = shift;
+
     # Check if we have a model class
-    if ($self->{model_class}) {
-        return $self->model_class->authenticate($self) if 
-            $self->model_class->can("authenticate"); 
+    if ( $self->{model_class} ) {
+        return $self->model_class->authenticate($self)
+          if $self->model_class->can("authenticate");
     }
-    return $self->authenticate($self); # Interface consistency is a Good Thing
+    return $self->authenticate($self);   # Interface consistency is a Good Thing
 }
 
-sub additional_data {}
+sub call_exception {
+    my $self = shift;
+    my ($error) = @_;
+
+    # Check if we have a model class
+    if (   $self->{model_class}
+        && $self->model_class->can('exception') )
+    {
+        my $status = $self->model_class->exception( $self, $error );
+        return $status if $status == OK;
+    }
+    return $self->exception($error);
+}
+
+sub additional_data { }
 
 sub authenticate { return OK }
 
+sub exception { return ERROR }
+
 sub parse_path {
     my $self = shift;
     $self->{path} ||= "frontpage";
     my @pi = split /\//, $self->{path};
     shift @pi while @pi and !$pi[0];
-    $self->{table} = shift @pi;
+    $self->{table}  = shift @pi;
     $self->{action} = shift @pi;
-    $self->{args} = \@pi;
+    $self->{args}   = \@pi;
 }
 
 =head1 NAME
@@ -261,9 +296,15 @@ L<Maypole::Workflow> documentation for what these are expected to do.
 =cut
 
 sub get_template_root { "." }
-sub get_request { }
-sub parse_location { die "Do not use Maypole directly; use Apache::MVC or similar" }
-sub send_output{ die "Do not use Maypole directly; use Apache::MVC or similar" }
+sub get_request       { }
+
+sub parse_location {
+    die "Do not use Maypole directly; use Apache::MVC or similar";
+}
+
+sub send_output {
+    die "Do not use Maypole directly; use Apache::MVC or similar";
+}
 
 =head1 SEE ALSO