Add the code for class serve_mixin, it will be used by cmdctl and xfrout. TODO, 1. add test case for ServeMixIn. 2 change the code of cmdctl and xfrout to use it.

git-svn-id: svn://bind10.isc.org/svn/bind10/branches/trac352@3064 e5f2f494-b856-4b98-b285-d166d9295462

src/lib/python/isc/utils/Makefile.am

@@ -1,5 +1,5 @@
 SUBDIRS = tests
 
-python_PYTHON = __init__.py process.py
+python_PYTHON = __init__.py process.py serve_mixin.py
 
 pythondir = $(pyexecdir)/isc/utils

src/lib/python/isc/utils/__init__.py

@@ -0,0 +1 @@
+from isc.utils.serve_mixin import *

src/lib/python/isc/utils/serve_mixin.py

@@ -0,0 +1,60 @@
+# Copyright (C) 2010  Internet Systems Consortium.
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SYSTEMS CONSORTIUM
+# DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+# INTERNET SYSTEMS CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
+# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
+# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
+# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+import threading
+import socket
+import select
+
+class ServeMixIn():
+    '''Mix-In class to override the function serve_forever()
+    and shutdown() in class socketserver. 
+    '''
+    _serving = False
+    _is_shut_down = threading.Event()
+    _read_sock, _write_sock = socket.socketpair()
+
+    def serve_forever(self, poll_interval=0.5):
+        ''' Override the serve_forever() in class BaseServer.
+        use one socket pair to wake up the select when shutdown()
+        is called in anther thread.
+        '''        
+        self._serving = True
+        self._is_shut_down.clear()
+        while self._serving:
+            # block until the self.socket or self._read_sock is readable 
+            try:
+                r, w, e = select.select([self, self._read_sock], [], [])
+            except select.error as err:
+                if err.args[0] != EINTR:
+                    raise
+                else:
+                    continue
+            if r:
+                if self._read_sock in r:
+                    break
+                else:
+                    self._handle_request_noblock()
+
+        self._is_shut_down.set()
+
+    def shutdown(self):
+        '''Stops the serve_forever loop.
+        Blocks until the loop has finished, the function should be called
+        in another thread when serve_forever is running, or it will block.
+        '''
+        self._serving = False
+        self._write_sock.send(b'anydata') # make self._read_sock readable.
+        self._is_shut_down.wait()
+

src/lib/python/isc/utils/tests/Makefile.am

@@ -1,4 +1,4 @@
-PYTESTS = process_test.py
+PYTESTS = process_test.py serve_mixin.py
 EXTRA_DIST = $(PYTESTS)
 
 # later will have configure option to choose this, like: coverage run --branch

src/lib/python/isc/utils/tests/serve_mixin_test.py

@@ -0,0 +1,26 @@
+# Copyright (C) 2010  Internet Systems Consortium.
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SYSTEMS CONSORTIUM
+# DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+# INTERNET SYSTEMS CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
+# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
+# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
+# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+import unittest
+import isc.utils.serve_mixin
+
+class TestServeMixIn(unittest.TestCase):
+    def test_serve_forever(self):
+        pass
+
+   if __name__== "__main__":
+    unittest.main()
+
+