logging: add logging handler SysLogHandler

- it properly handle unicode,
 - it wraps long content as multiple log lines.

entrouvert/logging/handlers.py

@@ -0,0 +1,50 @@
+import logging.handlers
+import socket
+try:
+    import codecs
+except ImportError:
+    codecs = None
+
+class SysLogHandler(logging.handlers.SysLogHandler):
+    def emit(self, record):
+        """
+        Emit a record.
+
+        The record is formatted, and then sent to the syslog server. If
+        exception information is present, it is NOT sent to the server.
+        """
+        source_msg = self.format(record)
+        """
+        We need to convert record level to lowercase, maybe this will
+        change in the future.
+        """
+        prio = '<%d>' % self.encodePriority(self.facility,
+                                            self.mapPriority(record.levelname))
+        max_length = 70
+        i = 0
+        while source_msg[i:]:
+            msg = source_msg[i:i+max_length] + '\000'
+            if i:
+                msg = ' ' + msg
+            i += max_length
+            # Message is a string. Convert to bytes as required by RFC 5424
+            if type(msg) is unicode:
+                msg = msg.encode('utf-8')
+                if codecs:
+                    msg = codecs.BOM_UTF8 + msg
+            msg = prio + msg
+            try:
+                if self.unixsocket:
+                    try:
+                        self.socket.send(msg)
+                    except socket.error:
+                        self._connect_unixsocket(self.address)
+                        self.socket.send(msg)
+                elif self.socktype == socket.SOCK_DGRAM:
+                    self.socket.sendto(msg, self.address)
+                else:
+                    self.socket.sendall(msg)
+            except (KeyboardInterrupt, SystemExit):
+                raise
+            except:
+                self.handleError(record)