Extract ActionController rescue templates into Rescue and ShowExceptions middleware.

This commit breaks all exception catching plugins like ExceptionNotifier. These plugins should be rewritten as middleware instead overriding Controller#rescue_action_in_public.

11 files changed, 281 insertions, 7 deletions

diff --git a/actionpack/lib/action_dispatch/middleware/rescue.rb b/actionpack/lib/action_dispatch/middleware/rescue.rb
new file mode 100644
index 0000000000..1456825526
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/rescue.rb
@@ -0,0 +1,14 @@
+module ActionDispatch
+  class Rescue
+    def initialize(app, rescuer)
+      @app, @rescuer = app, rescuer
+    end
+
+    def call(env)
+      @app.call(env)
+    rescue Exception => exception
+      env['action_dispatch.rescue.exception'] = exception
+      @rescuer.call(env)
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/middleware/show_exceptions.rb b/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
new file mode 100644
index 0000000000..791254cdf2
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
@@ -0,0 +1,142 @@
+module ActionDispatch
+  class ShowExceptions
+    include StatusCodes
+
+    LOCALHOST = '127.0.0.1'.freeze
+
+    DEFAULT_RESCUE_RESPONSE = :internal_server_error
+    DEFAULT_RESCUE_RESPONSES = {
+      'ActionController::RoutingError'             => :not_found,
+      'ActionController::UnknownAction'            => :not_found,
+      'ActiveRecord::RecordNotFound'               => :not_found,
+      'ActiveRecord::StaleObjectError'             => :conflict,
+      'ActiveRecord::RecordInvalid'                => :unprocessable_entity,
+      'ActiveRecord::RecordNotSaved'               => :unprocessable_entity,
+      'ActionController::MethodNotAllowed'         => :method_not_allowed,
+      'ActionController::NotImplemented'           => :not_implemented,
+      'ActionController::InvalidAuthenticityToken' => :unprocessable_entity
+    }
+
+    DEFAULT_RESCUE_TEMPLATE = 'diagnostics'
+    DEFAULT_RESCUE_TEMPLATES = {
+      'ActionView::MissingTemplate'       => 'missing_template',
+      'ActionController::RoutingError'    => 'routing_error',
+      'ActionController::UnknownAction'   => 'unknown_action',
+      'ActionView::TemplateError'         => 'template_error'
+    }
+
+    RESCUES_TEMPLATE_PATH = File.join(File.dirname(__FILE__), 'templates')
+
+    cattr_accessor :rescue_responses
+    @@rescue_responses = Hash.new(DEFAULT_RESCUE_RESPONSE)
+    @@rescue_responses.update DEFAULT_RESCUE_RESPONSES
+
+    cattr_accessor :rescue_templates
+    @@rescue_templates = Hash.new(DEFAULT_RESCUE_TEMPLATE)
+    @@rescue_templates.update DEFAULT_RESCUE_TEMPLATES
+
+    def initialize(app, consider_all_requests_local = false)
+      @app = app
+      @consider_all_requests_local = consider_all_requests_local
+    end
+
+    def call(env)
+      @app.call(env)
+    rescue Exception => exception
+      log_error(exception) if logger
+
+      request = Request.new(env)
+      if @consider_all_requests_local || local_request?(request)
+        rescue_action_locally(request, exception)
+      else
+        rescue_action_in_public(exception)
+      end
+    end
+
+    private
+      # Render detailed diagnostics for unhandled exceptions rescued from
+      # a controller action.
+      def rescue_action_locally(request, exception)
+        template = ActionView::Base.new([RESCUES_TEMPLATE_PATH],
+          :template => template,
+          :request => request,
+          :exception => exception
+        )
+        file = "rescues/#{@@rescue_templates[exception.class.name]}.erb"
+        body = template.render(:file => file, :layout => 'rescues/layout.erb')
+
+        headers = {'Content-Type' => 'text/html', 'Content-Length' => body.length.to_s}
+        status = status_code(exception)
+
+        [status, headers, body]
+      end
+
+      # Attempts to render a static error page based on the
+      # <tt>status_code</tt> thrown, or just return headers if no such file
+      # exists. At first, it will try to render a localized static page.
+      # For example, if a 500 error is being handled Rails and locale is :da,
+      # it will first attempt to render the file at <tt>public/500.da.html</tt>
+      # then attempt to render <tt>public/500.html</tt>. If none of them exist,
+      # the body of the response will be left empty.
+      def rescue_action_in_public(exception)
+        status = status_code(exception)
+        locale_path = "#{public_path}/#{status}.#{I18n.locale}.html" if I18n.locale
+        path = "#{public_path}/#{status}.html"
+
+        if locale_path && File.exist?(locale_path)
+          render_public_file(status, locale_path)
+        elsif File.exist?(path)
+          render_public_file(status, path)
+        else
+          [status, {'Content-Type' => 'text/html', 'Content-Length' => '0'}, []]
+        end
+      end
+
+      # True if the request came from localhost, 127.0.0.1.
+      def local_request?(request)
+        request.remote_addr == LOCALHOST && request.remote_ip == LOCALHOST
+      end
+
+      def render_public_file(status, path)
+        body = File.read(path)
+        [status, {'Content-Type' => 'text/html', 'Content-Length' => body.length.to_s}, body]
+      end
+
+      def status_code(exception)
+        interpret_status(@@rescue_responses[exception.class.name]).to_i
+      end
+
+      def public_path
+        if defined?(Rails)
+          Rails.public_path
+        else
+          "public"
+        end
+      end
+
+      def log_error(exception) #:doc:
+        ActiveSupport::Deprecation.silence do
+          if ActionView::TemplateError === exception
+            logger.fatal(exception.to_s)
+          else
+            logger.fatal(
+              "\n#{exception.class} (#{exception.message}):\n  " +
+              clean_backtrace(exception).join("\n  ") + "\n\n"
+            )
+          end
+        end
+      end
+
+      def clean_backtrace(exception)
+        defined?(Rails) && Rails.respond_to?(:backtrace_cleaner) ?
+          Rails.backtrace_cleaner.clean(exception.backtrace) :
+          exception.backtrace
+      end
+
+      def logger
+        if defined?(Rails.logger)
+          Rails.logger
+        end
+      end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb
new file mode 100644
index 0000000000..5224403dab
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb
@@ -0,0 +1,24 @@
+<% unless @exception.blamed_files.blank? %>
+  <% if (hide = @exception.blamed_files.length > 8) %>
+    <a href="#" onclick="document.getElementById('blame_trace').style.display='block'; return false;">Show blamed files</a>
+  <% end %>
+  <pre id="blame_trace" <%='style="display:none"' if hide %>><code><%=h @exception.describe_blame %></code></pre>
+<% end %>
+
+<%
+  clean_params = @request.parameters.clone
+  clean_params.delete("action")
+  clean_params.delete("controller")
+
+  request_dump = clean_params.empty? ? 'None' : clean_params.inspect.gsub(',', ",\n")
+%>
+
+<h2 style="margin-top: 30px">Request</h2>
+<p><b>Parameters</b>: <pre><%=h request_dump %></pre></p>
+
+<p><a href="#" onclick="document.getElementById('session_dump').style.display='block'; return false;">Show session dump</a></p>
+<div id="session_dump" style="display:none"><%= debug(@request.session.instance_variable_get("@data")) %></div>
+
+
+<h2 style="margin-top: 30px">Response</h2>
+<p><b>Headers</b>: <pre><%=h @response ? @response.headers.inspect.gsub(',', ",\n") : 'None' %></pre></p>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/_trace.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/_trace.erb
new file mode 100644
index 0000000000..bb2d8375bd
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/_trace.erb
@@ -0,0 +1,26 @@
+<%
+  traces = [
+    ["Application Trace", @exception.application_backtrace],
+    ["Framework Trace", @exception.framework_backtrace],
+    ["Full Trace", @exception.clean_backtrace]
+  ]
+  names = traces.collect {|name, trace| name}
+%>
+
+<p><code>RAILS_ROOT: <%= defined?(RAILS_ROOT) ? RAILS_ROOT : "unset" %></code></p>
+
+<div id="traces">
+  <% names.each do |name| %>
+    <%
+      show = "document.getElementById('#{name.gsub /\s/, '-'}').style.display='block';"
+      hide = (names - [name]).collect {|hide_name| "document.getElementById('#{hide_name.gsub /\s/, '-'}').style.display='none';"}
+    %>
+    <a href="#" onclick="<%= hide %><%= show %>; return false;"><%= name %></a> <%= '|' unless names.last == name %>
+  <% end %>
+
+  <% traces.each do |name, trace| %>
+    <div id="<%= name.gsub /\s/, '-' %>" style="display: <%= name == "Application Trace" ? 'block' : 'none' %>;">
+      <pre><code><%= trace.join "\n" %></code></pre>
+    </div>
+  <% end %>
+</div>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb
new file mode 100644
index 0000000000..693e56270a
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb
@@ -0,0 +1,10 @@
+<h1>
+  <%=h @exception.class.to_s %>
+  <% if @request.parameters['controller'] %>
+    in <%=h @request.parameters['controller'].humanize %>Controller<% if @request.parameters['action'] %>#<%=h @request.parameters['action'] %><% end %>
+  <% end %>
+</h1>
+<pre><%=h @exception.clean_message %></pre>
+
+<%= render :file => "rescues/_trace.erb" %>
+<%= render :file => "rescues/_request_and_response.erb" %>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb
new file mode 100644
index 0000000000..6c32fb17b8
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/layout.erb
@@ -0,0 +1,29 @@
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head>
+  <title>Action Controller: Exception caught</title>
+  <style>
+    body { background-color: #fff; color: #333; }
+
+    body, p, ol, ul, td {
+      font-family: verdana, arial, helvetica, sans-serif;
+      font-size:   13px;
+      line-height: 18px;
+    }
+
+    pre {
+      background-color: #eee;
+      padding: 10px;
+      font-size: 11px;
+    }
+
+    a { color: #000; }
+    a:visited { color: #666; }
+    a:hover { color: #fff; background-color:#000; }
+  </style>
+</head>
+<body>
+
+<%= yield %>
+
+</body>
+</html>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/missing_template.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/missing_template.erb
new file mode 100644
index 0000000000..dbfdf76947
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/missing_template.erb
@@ -0,0 +1,2 @@
+<h1>Template is missing</h1>
+<p><%=h @exception.message %></p>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/routing_error.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/routing_error.erb
new file mode 100644
index 0000000000..ccfa858cce
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/routing_error.erb
@@ -0,0 +1,10 @@
+<h1>Routing Error</h1>
+<p><pre><%=h @exception.message %></pre></p>
+<% unless @exception.failures.empty? %><p>
+  <h2>Failure reasons:</h2>
+  <ol>
+  <% @exception.failures.each do |route, reason| %>
+    <li><code><%=h route.inspect.gsub('\\', '') %></code> failed because <%=h reason.downcase %></li>
+  <% end %>
+  </ol>
+</p><% end %>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/template_error.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/template_error.erb
new file mode 100644
index 0000000000..02fa18211d
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/template_error.erb
@@ -0,0 +1,21 @@
+<h1>
+  <%=h @exception.original_exception.class.to_s %> in
+  <%=h @request.parameters["controller"].capitalize if @request.parameters["controller"]%>#<%=h @request.parameters["action"] %>
+</h1>
+
+<p>
+  Showing <i><%=h @exception.file_name %></i> where line <b>#<%=h @exception.line_number %></b> raised:
+  <pre><code><%=h @exception.message %></code></pre>
+</p>
+
+<p>Extracted source (around line <b>#<%=h @exception.line_number %></b>):
+<pre><code><%=h @exception.source_extract %></code></pre></p>
+
+<p><%=h @exception.sub_template_message %></p>
+
+<% @real_exception = @exception
+   @exception = @exception.original_exception || @exception %>
+<%= render :file => "rescues/_trace.erb" %>
+<% @exception = @real_exception %>
+
+<%= render :file => "rescues/_request_and_response.erb" %>
diff --git a/actionpack/lib/action_dispatch/middleware/templates/rescues/unknown_action.erb b/actionpack/lib/action_dispatch/middleware/templates/rescues/unknown_action.erb
new file mode 100644
index 0000000000..683379da10
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/templates/rescues/unknown_action.erb
@@ -0,0 +1,2 @@
+<h1>Unknown action</h1>
+<p><%=h @exception.message %></p>
diff --git a/actionpack/lib/action_dispatch/testing/assertions/response.rb b/actionpack/lib/action_dispatch/testing/assertions/response.rb
index 92e3da580e..501a7c4dfb 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/response.rb
@@ -31,13 +31,7 @@ module ActionDispatch
         elsif type.is_a?(Symbol) && @response.response_code == ActionDispatch::StatusCodes::SYMBOL_TO_STATUS_CODE[type]
           assert_block("") { true } # to count the assertion
         else
-          if @controller && @response.error?
-            exception = @controller.template.instance_variable_get(:@exception)
-            exception_message = exception && exception.message
-            assert_block(build_message(message, "Expected response to be a <?>, but was <?>\n<?>", type, @response.response_code, exception_message.to_s)) { false }
-          else
-            assert_block(build_message(message, "Expected response to be a <?>, but was <?>", type, @response.response_code)) { false }
-          end
+          assert_block(build_message(message, "Expected response to be a <?>, but was <?>", type, @response.response_code)) { false }
         end
       end