aboutsummaryrefslogtreecommitdiffstats
path: root/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb
blob: 8974258cf7bee931e879fd7933e9693141a2bc33 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
require 'action_dispatch/http/request'
require 'action_dispatch/middleware/exception_wrapper'
require 'action_dispatch/routing/inspector'
require 'action_view'
require 'action_view/base'

require 'pp'

module ActionDispatch
  # This middleware is responsible for logging exceptions and
  # showing a debugging page in case the request is local.
  class DebugExceptions
    RESCUES_TEMPLATE_PATH = File.expand_path('../templates', __FILE__)

    class DebugView < ActionView::Base
      def debug_params(params)
        clean_params = params.clone
        clean_params.delete("action")
        clean_params.delete("controller")

        if clean_params.empty?
          'None'
        else
          PP.pp(clean_params, "", 200)
        end
      end

      def debug_headers(headers)
        if headers.present?
          headers.inspect.gsub(',', ",\n")
        else
          'None'
        end
      end

      def debug_hash(object)
        object.to_hash.sort_by { |k, _| k.to_s }.map { |k, v| "#{k}: #{v.inspect rescue $!.message}" }.join("\n")
      end

      def render(*)
        if logger = ActionView::Base.logger
          logger.silence { super }
        else
          super
        end
      end
    end

    def initialize(app, routes_app = nil, response_format = :default)
      @app             = app
      @routes_app      = routes_app
      @response_format = response_format
    end

    def call(env)
      request = ActionDispatch::Request.new env
      _, headers, body = response = @app.call(env)

      if headers['X-Cascade'] == 'pass'
        body.close if body.respond_to?(:close)
        raise ActionController::RoutingError, "No route matches [#{env['REQUEST_METHOD']}] #{env['PATH_INFO'].inspect}"
      end

      response
    rescue Exception => exception
      raise exception unless request.show_exceptions?
      render_exception(request, exception)
    end

    private

    def render_exception(request, exception)
      backtrace_cleaner = request.get_header('action_dispatch.backtrace_cleaner')
      wrapper = ExceptionWrapper.new(backtrace_cleaner, exception)
      log_error(request, wrapper)

      if request.get_header('action_dispatch.show_detailed_exceptions')
        content_type = request.formats.first

        if api_request?(content_type)
          render_for_api_request(content_type, wrapper)
        else
          render_for_browser_request(request, wrapper)
        end
      else
        raise exception
      end
    end

    def render_for_browser_request(request, wrapper)
      template = create_template(request, wrapper)
      file = "rescues/#{wrapper.rescue_template}"

      if request.xhr?
        body = template.render(template: file, layout: false, formats: [:text])
        format = "text/plain"
      else
        body = template.render(template: file, layout: 'rescues/layout')
        format = "text/html"
      end
      render(wrapper.status_code, body, format)
    end

    def render_for_api_request(content_type, wrapper)
      body = {
        status: wrapper.status_code,
        error:  Rack::Utils::HTTP_STATUS_CODES.fetch(
          wrapper.status_code,
          Rack::Utils::HTTP_STATUS_CODES[500]
        ),
        exception: wrapper.exception.inspect,
        traces: wrapper.traces
      }

      to_format = "to_#{content_type.to_sym}"

      if content_type && body.respond_to?(to_format)
        formatted_body = body.public_send(to_format)
        format = content_type
      else
        formatted_body = body.to_json
        format = Mime[:json]
      end

      render(wrapper.status_code, formatted_body, format)
    end

    def create_template(request, wrapper)
      traces = wrapper.traces

      trace_to_show = 'Application Trace'
      if traces[trace_to_show].empty? && wrapper.rescue_template != 'routing_error'
        trace_to_show = 'Full Trace'
      end

      if source_to_show = traces[trace_to_show].first
        source_to_show_id = source_to_show[:id]
      end

      DebugView.new([RESCUES_TEMPLATE_PATH],
        request: request,
        exception: wrapper.exception,
        traces: traces,
        show_source_idx: source_to_show_id,
        trace_to_show: trace_to_show,
        routes_inspector: routes_inspector(wrapper.exception),
        source_extracts: wrapper.source_extracts,
        line_number: wrapper.line_number,
        file: wrapper.file
      )
    end

    def render(status, body, format)
      [status, {'Content-Type' => "#{format}; charset=#{Response.default_charset}", 'Content-Length' => body.bytesize.to_s}, [body]]
    end

    def log_error(request, wrapper)
      logger = logger(request)
      return unless logger

      exception = wrapper.exception

      trace = wrapper.application_trace
      trace = wrapper.framework_trace if trace.empty?

      ActiveSupport::Deprecation.silence do
        logger.fatal "  "
        logger.fatal "#{exception.class} (#{exception.message}):"
        log_array logger, exception.annoted_source_code if exception.respond_to?(:annoted_source_code)
        logger.fatal "  "
        log_array logger, trace
      end
    end

    def log_array(logger, array)
      array.map { |line| logger.fatal line }
    end

    def logger(request)
      request.logger || ActionView::Base.logger || stderr_logger
    end

    def stderr_logger
      @stderr_logger ||= ActiveSupport::Logger.new($stderr)
    end

    def routes_inspector(exception)
      if @routes_app.respond_to?(:routes) && (exception.is_a?(ActionController::RoutingError) || exception.is_a?(ActionView::Template::Error))
        ActionDispatch::Routing::RoutesInspector.new(@routes_app.routes.routes)
      end
    end

    def api_request?(content_type)
      @response_format == :api && !content_type.html?
    end
  end
end