1 # Copyright (C) 2014 Ipsilon Project Contributors
3 # See the file named COPYING for the project license
12 def log_request_response():
13 '''Log the contents of the request and subsequent response.
15 This is run as a tool hook and should be run as the last hook
16 (on_end_resource) just before the server writes the response to
17 the client. The tool is registered like this:
19 cherrypy.tools.log_request_response = \
20 cherrypy.Tool('on_end_resource', log_request_response)
22 Then the logging can be enabled or disabled via the config option,
23 for example to turn the logging on via a config dict add this
26 'tools.log_request_response.on': True,
28 or for a config file add this line:
30 tools.log_request_response.on = True
32 At first blush it would seem easy to log the request received and
33 the response emitted, just hook those locations and output the raw
34 data. Unfortunately there are no such locations in cherrypy where
35 you have access to the raw input and output data. The complicating
38 * Input data is consumed by the Request object off a file object
39 which cannot seek back (i.e. rewind), once the data is read it
40 cannot be read again. Therefore any attempt to log the raw input
41 will starve read operations done by the Request object to read
44 * Automatic consumption and processing of the body contents is
45 enabled by default (controlled by the
46 request.process_request_body config option). You generally do
47 not want to turn these automatic request processors off because
48 they provide valuable input processing useful to the request
49 processing pipeline (e.g. when Content-Type is
50 application/x-www-form-urlencoded, or multipart/form-data or
51 multipart). Most cherrypy page handlers expect this
52 pre-processing to have been performed and the 'cooked' data to
53 be availabe on the Request object. Thus rather than logging the
54 raw input HTTP which will have been consumed by the request
55 processing logic we are forced into logging only the 'cooked'
56 values available to us after the request has been read and
59 * The response body may not be available if response streaming is
60 enabled. This is because control is passed directly to the
61 object writing the data to the client bypassing the normal
62 cherrypy hooks. Fortunately streaming is not recommended and we
63 can expect it will be disabled. When streaming is disabled the
64 response body can be composed as:
68 - a generator yielding chunks of strings
70 When the response body is a string or list of strings logging
71 the body and then passing down the pipeline to be written to the
72 client is trivial. However when part of the body is produced by
73 a generator we must run the generator to produce that part of
74 the body and store it as a string. This is an issue equivalent
75 to not being able to re-read a file object as seen in the input
76 situation. Once the generator has run it cannot be run
77 again. Therefore we consume all the body output, store it in a
78 string, log it and then replace the request body contents with
79 the body string we formed. It's this body string which is
80 subsequently sent down the processing pipeline to be written to
85 # --- Begin local functions ---
87 def indent_text(text, level=0, indent=' '):
89 Input is a block of text potentially containing newlines which
90 seperate the text into a sequence of lines. The text block is
91 split into individual lines and indented according to the
92 indentation level. The width of the indent is controlled by
93 the optional indent parameter.
95 The result is a single block of text where each of the
96 original lines of text are indented.
99 f = cStringIO.StringIO()
101 lines = text.split('\n')
103 # Do not output trailing newline
104 if lines and lines[-1] == '':
108 f.write(indent*level)
112 string = f.getvalue()
116 def print_part(part):
118 Format a cherrypy._cpreqbody.Part object into a string.
120 When the request Content-Type is a multipart cherrypy splits
121 each part of the multipart into a Part object containing
122 information about the part and it's content.
124 f = cStringIO.StringIO()
126 f.write(indent_text('Name = %s\n' % part.name))
128 f.write(indent_text('Headers:\n'))
129 for name, value in part.headers.items():
130 f.write(indent_text('%s: %s\n' % (name, value), 1))
132 f.write(indent_text("Body:\n"))
133 f.write(indent_text(part.fullvalue(), 1))
135 string = f.getvalue()
139 def collapse_body(body):
140 '''The cherrypy response body can be:
144 * generator yielding a string
146 Generators are typically used for file contents but any
147 cherrypy response is permitted to use a generator to provide
148 the body of the response.
150 Strings and lists of strings are immediately available and
151 stored in the request object. During normal cherrypy
152 processing when writing the response to the client response
153 data which is provided by a generator will be iterated over
154 and written to the client. In order for us to be able to log
155 all the response data prior to it being sent to the client we
156 must also iterate over the generator provided content, however
157 this exhausts the generator making it unavailable to be
158 written to the client.
160 To solve this problem we collect all the response data. Now we
161 have the full body contents, we can log it and then set this
162 as the new body contents for remainder of the processing
163 pipeline to act upon (i.e. sent to the client)
165 f = cStringIO.StringIO()
170 string = f.getvalue()
174 # --- End local functions ---
176 f = cStringIO.StringIO()
177 request = cherrypy.serving.request
178 remote = request.remote
183 f.write(indent_text("<Request> [%s] %s\n" %
184 (remote.name or remote.ip, request.request_line), 0))
188 f.write(indent_text("Headers:\n", 1))
189 for name, value in request.headers.items():
190 f.write(indent_text("%s: %s\n" % (name, value), 2))
192 # Request parameters from URL query string and
193 # x-www-form-urlencoded POST data
194 if request.body.params:
195 f.write(indent_text("Params:\n", 1))
196 for name, value in request.body.params.items():
197 # Multi-valued paramater is in a list
198 if isinstance(value, list):
199 for i, item in enumerate(value):
200 # Might be a multipart Part object, if so format it
201 if getattr(item, "part_class", None):
202 f.write(indent_text("%s[%s]:\n" % (name, i), 2))
203 f.write(indent_text(print_part(item), 3))
205 # Not a mulitpart, just write it as a string
206 f.write(indent_text("%s[%s]: %s\n" %
209 # Just a string value
210 f.write(indent_text("%s: %s\n" % (name, value), 2))
212 # If the body is multipart format each of the parts
213 if request.body.parts:
214 f.write(indent_text("Body Parts:\n"))
215 for i, part in enumerate(request.body.parts):
216 f.write(indent_text("Part %s name=%s:\n" % (i, part.name), 3))
217 f.write(indent_text(print_part(part), 4))
222 response = cherrypy.response
223 f.write(indent_text("<Response> %s\n" % response.status, 0))
225 # Log the response headers
226 if response.header_list:
227 f.write(indent_text("Headers:\n", 1))
228 for name, value in response.header_list:
229 f.write(indent_text("%s: %s\n" % (name, value), 2))
231 # Log the response body
233 # We can only do this if the response is not streaming because we have
234 # no way to hook the streaming content.
235 f.write(indent_text("Body:\n", 1))
238 f.write(indent_text("body omitted because response is streaming\n", 2))
240 response.body = collapse_body(response.body)
241 for chunk in response.body:
242 f.write(indent_text(chunk, 2))
244 string = f.getvalue()
248 cherrypy.tools.log_request_response = cherrypy.Tool('on_end_resource',
249 log_request_response)
256 buf = cStringIO.StringIO()
258 stack = traceback.extract_stack()
259 traceback.print_list(stack[:-2], file=buf)
261 stacktrace_string = buf.getvalue()
263 return stacktrace_string
266 def get_class_from_frame(frame_obj):
269 http://stackoverflow.com/questions/2203424/
270 python-how-to-retrieve-class-information-from-a-frame-object
272 At the frame object level, there does not seem to be any way
273 to find the actual python function object that has been
276 However, if your code relies on the common convention of naming
277 the instance parameter of a method self, then you could do this.
280 args, _, _, value_dict = inspect.getargvalues(frame_obj)
281 # Is the functions first parameter named 'self'?
282 if len(args) and args[0] == 'self':
283 # in that case, 'self' will be referenced in value_dict
284 instance = value_dict.get('self', None)
287 return getattr(instance, '__class__', None)
288 # return None otherwise
293 frame = inspect.stack()[2]
296 line_number = frame[2]
299 # Only report the last 3 components of the path
300 filename = os.sep.join(filename.split(os.sep)[-3:])
302 cls = Log.get_class_from_frame(frame_obj)
304 location = '%s:%s %s.%s()' % \
305 (filename, line_number, cls.__name__, func)
307 location = '%s:%s %s()' % (filename, line_number, func)
310 def debug(self, fact):
311 if cherrypy.config.get('debug', False):
312 location = Log.call_location()
313 cherrypy.log('DEBUG(%s): %s' % (location, fact))
315 # for compatibility with existing code
321 def error(self, fact):
322 cherrypy.log.error('ERROR: %s' % fact)
323 if cherrypy.config.get('stacktrace_on_error', False):
324 cherrypy.log.error(Log.stacktrace())