support handle exceptions

CHANGES.md

@@ -5,10 +5,17 @@ CHANGES
 
   * [Changes](https://github.com/migrs/rack-server-pages/compare/v0.0.4...master)
 
+  * Feature
+    - Handle exceptions
+      - Add `config.show_exceptions` option
+      - Invoke `on_error` filter when an exception is caught
+
   * Enhancement
-    - NotFound
+    - NotFound with 404 file
         - Rack::ServerPages::NotFound['404.html']
-    - On Error
+
+  * Bugfix
+    - Duplicated filters
 
 ### [0.0.4](https://github.com/migrs/rack-server-pages/tree/v0.0.4) / 2012-01-15
 

README.md

@@ -19,6 +19,7 @@ There are no controllers or models, just only views like a jsp, asp and php!
 - Include a partial template
 - Layout template
 - Before/After filters
+- Handle exceptions
 - Include helpers
 - Integrate with any rack applications (Rails, Sinatra, etc...)
 - Extremely simple and easy to use!

config.ru

@@ -26,6 +26,12 @@ module SampleHelper
 end
 
 run Rack::ServerPages.new { |config|
+  #config.show_exceptions = false
+
+  config.on_error do
+    response.body = ['Error!']
+  end
+
   config.helpers SampleHelper
   config.helpers do
     def sample4

lib/rack/server_pages.rb

@@ -71,7 +71,22 @@ def build_response(template, scope)
     def server_page(template)
       lambda do |env|
         @binding.new(env).tap do |scope|
-          catch(:halt) { @config.filter.invoke(scope) { build_response(template, scope) }}
+          catch(:halt) do
+            begin
+              @config.filter.invoke(scope, :before)
+              build_response(template, scope)
+            rescue
+              if @config.show_exceptions?
+                raise $!
+              else
+                scope.response.status = 500
+                scope.response['Content-Type'] ||= "text/html"
+                @config.filter.invoke(scope, :on_error)
+              end
+            ensure
+              @config.filter.invoke(scope, :after)
+            end
+          end
         end.response.finish
       end
     end
@@ -91,24 +106,20 @@ def [] type
       end
 
       def merge(other)
-        TYPES.each { |type| self[type].concat other[type] }
+        TYPES.each { |type| @filters[type].concat other[type] }
       end
 
       def merge_from_helpers(helpers)
         merge(self.class.extract_filters_from_helpers(helpers))
       end
 
       def add(type, *args, &block)
-        self[type] << block if block_given?
-        self[type].concat args unless args.empty?
+        @filters[type] << block if block_given?
+        @filters[type].concat args unless args.empty?
       end
 
-      def invoke(scope, type = nil)
-        if block_given?
-          invoke(scope, TYPES.first); yield scope; invoke(scope, TYPES.last)
-        else
-          self[type].each { |f| f.respond_to?(:bind) ? f.bind(scope).call : scope.instance_exec(&f) }
-        end
+      def invoke(scope, type)
+        @filters[type].each { |f| f.respond_to?(:bind) ? f.bind(scope).call : scope.instance_exec(&f) }
       end
 
       def self.extract_filters_from_helpers(helpers)
@@ -136,8 +147,10 @@ def self.hash_accessor(*names)
         end
       end
 
-      hash_accessor :view_path, :effective_path, :cache_control, :default_charset, :failure_app
+      hash_accessor :view_path, :effective_path, :cache_control, :default_charset, :failure_app, :show_exceptions
+
       attr_reader :filter
+
       def_delegators :filter, *Filter::TYPES
 
       def initialize
@@ -148,6 +161,14 @@ def initialize
         @filter  = Filter.new
       end
 
+      def show_exceptions?
+        if self[:show_exceptions].nil?
+          ENV['RACK_ENV'].nil? or (ENV['RACK_ENV'] == 'development')
+        else
+          self[:show_exceptions]
+        end
+      end
+
       def view_paths
         (v = self[:view_path]).kind_of?(Enumerable) ? v : [v.to_s]
       end