do not recommend multiple dispatch cycles in the cookbook

mojolicious · Apr 29, 2014 · 42bd0a8 · 42bd0a8
1 parent cf50ccb
commit 42bd0a8
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Showing 2 changed files with 56 additions and 55 deletions.
diff --git a/lib/Mojolicious/Guides/Cookbook.pod b/lib/Mojolicious/Guides/Cookbook.pod
@@ -668,42 +668,42 @@ which can be combined to solve some of hardest problems in web development.
   use Mojolicious::Lite;
   use Scalar::Util 'weaken';
 
-  # Emit "request" event early for requests that get upgraded to multipart
+  # Intercept multipart uploads and log each chunk received
   hook after_build_tx => sub {
     my $tx = shift;
+
+    # Subscribe to "upgrade" event to indentify multipart uploads
     weaken $tx;
-    $tx->req->content->on(upgrade => sub { $tx->emit('request') });
+    $tx->req->content->on(upgrade => sub {
+      my ($single, $multi) = @_;
+      return unless $tx->req->url->path->contains('/upload');
+
+      # Subscribe to "part" event to find the right one
+      return $tx->req->content->on(part => sub {
+        my ($multi, $single) = @_;
+
+        # Subscribe to "body" event of part to make sure we have all headers
+        $single->on(body => sub {
+          my $single = shift;
+
+          # Make sure we have the right part and replace "read" event
+          return unless $single->headers->content_disposition =~ /example/;
+          $single->unsubscribe('read')->on(read => sub {
+            my ($single, $bytes) = @_;
+
+            # Log size of every chunk we receive
+            app->log->debug(length($bytes) . ' bytes uploaded.');
+          });
+        });
+      });
+    });
   };
 
   # Upload form in DATA section
   get '/' => 'index';
 
-  # Streaming multipart upload (invoked twice, due to early "request" event)
-  post '/upload' => sub {
-    my $self = shift;
-
-    # First invocation, subscribe to "part" event to find the right one
-    return $self->req->content->on(part => sub {
-      my ($multi, $single) = @_;
-
-      # Subscribe to "body" event of part to make sure we have all headers
-      $single->on(body => sub {
-        my $single = shift;
-
-        # Make sure we have the right part and replace "read" event
-        return unless $single->headers->content_disposition =~ /example/;
-        $single->unsubscribe('read')->on(read => sub {
-          my ($single, $bytes) = @_;
-
-          # Log size of every chunk we receive
-          $self->app->log->debug(length($bytes) . ' bytes uploaded.');
-        });
-      });
-    }) unless $self->req->is_finished;
-
-    # Second invocation, render response
-    $self->render(text => 'Upload was successful.');
-  };
+  # Streaming multipart upload
+  post '/upload' => {text => 'Upload was successful.'};
 
   app->start;
   __DATA__

diff --git a/t/mojolicious/upload_stream_lite_app.t b/t/mojolicious/upload_stream_lite_app.t
@@ -10,64 +10,65 @@ use Mojolicious::Lite;
 use Scalar::Util 'weaken';
 use Test::Mojo;
 
-# Emit "request" event early for multipart requests under "/upload"
+# Stream multipart uploads into cache
+my %cache;
 hook after_build_tx => sub {
   my $tx = shift;
+
   weaken $tx;
   $tx->req->content->on(
     upgrade => sub {
-      $tx->emit('request') if $tx->req->url->path->contains('/upload');
-    }
-  );
-};
+      my ($single, $multi) = @_;
 
-my %cache;
-post '/upload/:id' => sub {
-  my $self = shift;
+      return unless $tx->req->url->path->contains('/upload');
 
-  # First invocation, prepare streaming
-  my $id = $self->param('id');
-  $self->req->content->on(
-    part => sub {
-      my ($multi, $single) = @_;
-      $single->on(
-        body => sub {
-          my $single = shift;
-          return unless $single->headers->content_disposition =~ /my_file/;
-          $single->unsubscribe('read');
-          $single->on(read => sub { $cache{$id} .= pop });
+      my $id = $tx->req->url->query->param('id');
+      $multi->on(
+        part => sub {
+          my ($multi, $single) = @_;
+          $single->on(
+            body => sub {
+              my $single = shift;
+              return unless $single->headers->content_disposition =~ /my_file/;
+              $single->unsubscribe('read');
+              $single->on(read => sub { $cache{$id} .= pop });
+            }
+          );
         }
       );
     }
   );
-  return unless $self->req->is_finished;
+};
 
-  # Second invocation, render response
+post '/upload' => sub {
+  my $self = shift;
+  my $id   = $self->param('id');
   $self->render(data => $cache{$id});
 };
 
-get '/download/:id' => sub {
+get '/download' => sub {
   my $self = shift;
   $self->render(data => $cache{$self->param('id')});
 };
 
 my $t = Test::Mojo->new;
 
 # Small upload
-$t->post_ok('/upload/23' => form => {my_file => {content => 'whatever'}})
+$t->post_ok('/upload?id=23' => form => {my_file => {content => 'whatever'}})
   ->status_is(200)->content_is('whatever');
 
 # Small download
-$t->get_ok('/download/23')->status_is(200)->content_is('whatever');
+$t->get_ok('/download?id=23')->status_is(200)->content_is('whatever');
 
 # Big upload
-$t->post_ok('/upload/24' => form => {my_file => {content => '1234' x 131072}})
+$t->post_ok(
+  '/upload?id=24' => form => {my_file => {content => '1234' x 131072}})
   ->status_is(200)->content_is('1234' x 131072);
 
 # Big download
-$t->get_ok('/download/24')->status_is(200)->content_is('1234' x 131072);
+$t->get_ok('/download?id=24')->status_is(200)->content_is('1234' x 131072);
 
 # Small download again
-$t->get_ok('/download/23')->status_is(200)->content_is('whatever');
+$t->get_ok('/download?id=23')->status_is(200)->content_is('whatever');
 
 done_testing();