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Diffstat (limited to 'cherrypy/_cplogging.py')
| -rwxr-xr-x | cherrypy/_cplogging.py | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/cherrypy/_cplogging.py b/cherrypy/_cplogging.py new file mode 100755 index 0000000..d6ca979 --- /dev/null +++ b/cherrypy/_cplogging.py @@ -0,0 +1,393 @@ +""" +Simple config +============= + +Although CherryPy uses the :mod:`Python logging module <logging>`, it does so +behind the scenes so that simple logging is simple, but complicated logging +is still possible. "Simple" logging means that you can log to the screen +(i.e. console/stdout) or to a file, and that you can easily have separate +error and access log files. + +Here are the simplified logging settings. You use these by adding lines to +your config file or dict. You should set these at either the global level or +per application (see next), but generally not both. + + * ``log.screen``: Set this to True to have both "error" and "access" messages + printed to stdout. + * ``log.access_file``: Set this to an absolute filename where you want + "access" messages written. + * ``log.error_file``: Set this to an absolute filename where you want "error" + messages written. + +Many events are automatically logged; to log your own application events, call +:func:`cherrypy.log`. + +Architecture +============ + +Separate scopes +--------------- + +CherryPy provides log managers at both the global and application layers. +This means you can have one set of logging rules for your entire site, +and another set of rules specific to each application. The global log +manager is found at :func:`cherrypy.log`, and the log manager for each +application is found at :attr:`app.log<cherrypy._cptree.Application.log>`. +If you're inside a request, the latter is reachable from +``cherrypy.request.app.log``; if you're outside a request, you'll have to obtain +a reference to the ``app``: either the return value of +:func:`tree.mount()<cherrypy._cptree.Tree.mount>` or, if you used +:func:`quickstart()<cherrypy.quickstart>` instead, via ``cherrypy.tree.apps['/']``. + +By default, the global logs are named "cherrypy.error" and "cherrypy.access", +and the application logs are named "cherrypy.error.2378745" and +"cherrypy.access.2378745" (the number is the id of the Application object). +This means that the application logs "bubble up" to the site logs, so if your +application has no log handlers, the site-level handlers will still log the +messages. + +Errors vs. Access +----------------- + +Each log manager handles both "access" messages (one per HTTP request) and +"error" messages (everything else). Note that the "error" log is not just for +errors! The format of access messages is highly formalized, but the error log +isn't--it receives messages from a variety of sources (including full error +tracebacks, if enabled). + + +Custom Handlers +=============== + +The simple settings above work by manipulating Python's standard :mod:`logging` +module. So when you need something more complex, the full power of the standard +module is yours to exploit. You can borrow or create custom handlers, formats, +filters, and much more. Here's an example that skips the standard FileHandler +and uses a RotatingFileHandler instead: + +:: + + #python + log = app.log + + # Remove the default FileHandlers if present. + log.error_file = "" + log.access_file = "" + + maxBytes = getattr(log, "rot_maxBytes", 10000000) + backupCount = getattr(log, "rot_backupCount", 1000) + + # Make a new RotatingFileHandler for the error log. + fname = getattr(log, "rot_error_file", "error.log") + h = handlers.RotatingFileHandler(fname, 'a', maxBytes, backupCount) + h.setLevel(DEBUG) + h.setFormatter(_cplogging.logfmt) + log.error_log.addHandler(h) + + # Make a new RotatingFileHandler for the access log. + fname = getattr(log, "rot_access_file", "access.log") + h = handlers.RotatingFileHandler(fname, 'a', maxBytes, backupCount) + h.setLevel(DEBUG) + h.setFormatter(_cplogging.logfmt) + log.access_log.addHandler(h) + + +The ``rot_*`` attributes are pulled straight from the application log object. +Since "log.*" config entries simply set attributes on the log object, you can +add custom attributes to your heart's content. Note that these handlers are +used ''instead'' of the default, simple handlers outlined above (so don't set +the "log.error_file" config entry, for example). +""" + +import datetime +import logging +# Silence the no-handlers "warning" (stderr write!) in stdlib logging +logging.Logger.manager.emittedNoHandlerWarning = 1 +logfmt = logging.Formatter("%(message)s") +import os +import sys + +import cherrypy +from cherrypy import _cperror + + +class LogManager(object): + """An object to assist both simple and advanced logging. + + ``cherrypy.log`` is an instance of this class. + """ + + appid = None + """The id() of the Application object which owns this log manager. If this + is a global log manager, appid is None.""" + + error_log = None + """The actual :class:`logging.Logger` instance for error messages.""" + + access_log = None + """The actual :class:`logging.Logger` instance for access messages.""" + + access_log_format = \ + '%(h)s %(l)s %(u)s %(t)s "%(r)s" %(s)s %(b)s "%(f)s" "%(a)s"' + + logger_root = None + """The "top-level" logger name. + + This string will be used as the first segment in the Logger names. + The default is "cherrypy", for example, in which case the Logger names + will be of the form:: + + cherrypy.error.<appid> + cherrypy.access.<appid> + """ + + def __init__(self, appid=None, logger_root="cherrypy"): + self.logger_root = logger_root + self.appid = appid + if appid is None: + self.error_log = logging.getLogger("%s.error" % logger_root) + self.access_log = logging.getLogger("%s.access" % logger_root) + else: + self.error_log = logging.getLogger("%s.error.%s" % (logger_root, appid)) + self.access_log = logging.getLogger("%s.access.%s" % (logger_root, appid)) + self.error_log.setLevel(logging.INFO) + self.access_log.setLevel(logging.INFO) + cherrypy.engine.subscribe('graceful', self.reopen_files) + + def reopen_files(self): + """Close and reopen all file handlers.""" + for log in (self.error_log, self.access_log): + for h in log.handlers: + if isinstance(h, logging.FileHandler): + h.acquire() + h.stream.close() + h.stream = open(h.baseFilename, h.mode) + h.release() + + def error(self, msg='', context='', severity=logging.INFO, traceback=False): + """Write the given ``msg`` to the error log. + + This is not just for errors! Applications may call this at any time + to log application-specific information. + + If ``traceback`` is True, the traceback of the current exception + (if any) will be appended to ``msg``. + """ + if traceback: + msg += _cperror.format_exc() + self.error_log.log(severity, ' '.join((self.time(), context, msg))) + + def __call__(self, *args, **kwargs): + """An alias for ``error``.""" + return self.error(*args, **kwargs) + + def access(self): + """Write to the access log (in Apache/NCSA Combined Log format). + + See http://httpd.apache.org/docs/2.0/logs.html#combined for format + details. + + CherryPy calls this automatically for you. Note there are no arguments; + it collects the data itself from + :class:`cherrypy.request<cherrypy._cprequest.Request>`. + + Like Apache started doing in 2.0.46, non-printable and other special + characters in %r (and we expand that to all parts) are escaped using + \\xhh sequences, where hh stands for the hexadecimal representation + of the raw byte. Exceptions from this rule are " and \\, which are + escaped by prepending a backslash, and all whitespace characters, + which are written in their C-style notation (\\n, \\t, etc). + """ + request = cherrypy.serving.request + remote = request.remote + response = cherrypy.serving.response + outheaders = response.headers + inheaders = request.headers + if response.output_status is None: + status = "-" + else: + status = response.output_status.split(" ", 1)[0] + + atoms = {'h': remote.name or remote.ip, + 'l': '-', + 'u': getattr(request, "login", None) or "-", + 't': self.time(), + 'r': request.request_line, + 's': status, + 'b': dict.get(outheaders, 'Content-Length', '') or "-", + 'f': dict.get(inheaders, 'Referer', ''), + 'a': dict.get(inheaders, 'User-Agent', ''), + } + for k, v in atoms.items(): + if isinstance(v, unicode): + v = v.encode('utf8') + elif not isinstance(v, str): + v = str(v) + # Fortunately, repr(str) escapes unprintable chars, \n, \t, etc + # and backslash for us. All we have to do is strip the quotes. + v = repr(v)[1:-1] + # Escape double-quote. + atoms[k] = v.replace('"', '\\"') + + try: + self.access_log.log(logging.INFO, self.access_log_format % atoms) + except: + self(traceback=True) + + def time(self): + """Return now() in Apache Common Log Format (no timezone).""" + now = datetime.datetime.now() + monthnames = ['jan', 'feb', 'mar', 'apr', 'may', 'jun', + 'jul', 'aug', 'sep', 'oct', 'nov', 'dec'] + month = monthnames[now.month - 1].capitalize() + return ('[%02d/%s/%04d:%02d:%02d:%02d]' % + (now.day, month, now.year, now.hour, now.minute, now.second)) + + def _get_builtin_handler(self, log, key): + for h in log.handlers: + if getattr(h, "_cpbuiltin", None) == key: + return h + + + # ------------------------- Screen handlers ------------------------- # + + def _set_screen_handler(self, log, enable, stream=None): + h = self._get_builtin_handler(log, "screen") + if enable: + if not h: + if stream is None: + stream=sys.stderr + h = logging.StreamHandler(stream) + h.setFormatter(logfmt) + h._cpbuiltin = "screen" + log.addHandler(h) + elif h: + log.handlers.remove(h) + + def _get_screen(self): + h = self._get_builtin_handler + has_h = h(self.error_log, "screen") or h(self.access_log, "screen") + return bool(has_h) + + def _set_screen(self, newvalue): + self._set_screen_handler(self.error_log, newvalue, stream=sys.stderr) + self._set_screen_handler(self.access_log, newvalue, stream=sys.stdout) + screen = property(_get_screen, _set_screen, + doc="""Turn stderr/stdout logging on or off. + + If you set this to True, it'll add the appropriate StreamHandler for + you. If you set it to False, it will remove the handler. + """) + + # -------------------------- File handlers -------------------------- # + + def _add_builtin_file_handler(self, log, fname): + h = logging.FileHandler(fname) + h.setFormatter(logfmt) + h._cpbuiltin = "file" + log.addHandler(h) + + def _set_file_handler(self, log, filename): + h = self._get_builtin_handler(log, "file") + if filename: + if h: + if h.baseFilename != os.path.abspath(filename): + h.close() + log.handlers.remove(h) + self._add_builtin_file_handler(log, filename) + else: + self._add_builtin_file_handler(log, filename) + else: + if h: + h.close() + log.handlers.remove(h) + + def _get_error_file(self): + h = self._get_builtin_handler(self.error_log, "file") + if h: + return h.baseFilename + return '' + def _set_error_file(self, newvalue): + self._set_file_handler(self.error_log, newvalue) + error_file = property(_get_error_file, _set_error_file, + doc="""The filename for self.error_log. + + If you set this to a string, it'll add the appropriate FileHandler for + you. If you set it to ``None`` or ``''``, it will remove the handler. + """) + + def _get_access_file(self): + h = self._get_builtin_handler(self.access_log, "file") + if h: + return h.baseFilename + return '' + def _set_access_file(self, newvalue): + self._set_file_handler(self.access_log, newvalue) + access_file = property(_get_access_file, _set_access_file, + doc="""The filename for self.access_log. + + If you set this to a string, it'll add the appropriate FileHandler for + you. If you set it to ``None`` or ``''``, it will remove the handler. + """) + + # ------------------------- WSGI handlers ------------------------- # + + def _set_wsgi_handler(self, log, enable): + h = self._get_builtin_handler(log, "wsgi") + if enable: + if not h: + h = WSGIErrorHandler() + h.setFormatter(logfmt) + h._cpbuiltin = "wsgi" + log.addHandler(h) + elif h: + log.handlers.remove(h) + + def _get_wsgi(self): + return bool(self._get_builtin_handler(self.error_log, "wsgi")) + + def _set_wsgi(self, newvalue): + self._set_wsgi_handler(self.error_log, newvalue) + wsgi = property(_get_wsgi, _set_wsgi, + doc="""Write errors to wsgi.errors. + + If you set this to True, it'll add the appropriate + :class:`WSGIErrorHandler<cherrypy._cplogging.WSGIErrorHandler>` for you + (which writes errors to ``wsgi.errors``). + If you set it to False, it will remove the handler. + """) + + +class WSGIErrorHandler(logging.Handler): + "A handler class which writes logging records to environ['wsgi.errors']." + + def flush(self): + """Flushes the stream.""" + try: + stream = cherrypy.serving.request.wsgi_environ.get('wsgi.errors') + except (AttributeError, KeyError): + pass + else: + stream.flush() + + def emit(self, record): + """Emit a record.""" + try: + stream = cherrypy.serving.request.wsgi_environ.get('wsgi.errors') + except (AttributeError, KeyError): + pass + else: + try: + msg = self.format(record) + fs = "%s\n" + import types + if not hasattr(types, "UnicodeType"): #if no unicode support... + stream.write(fs % msg) + else: + try: + stream.write(fs % msg) + except UnicodeError: + stream.write(fs % msg.encode("UTF-8")) + self.flush() + except: + self.handleError(record) |