Adding a means to connect back to a pydevd debugger.

That patch allows a developer to remotely run a pydev debugger and have the
keystone-all process connect back to it.  Two command line options are
introduced:
    --pydev-debug-host <host>
    --pydev-debug-port <port>
both of the above options are required to enable this behavior.

This patch only enables this behavior when the service is started with
keystone-all.  In the future parts of this patch can be used to enable
this behavior when running in Apache.

Change-Id: I92f99fa34112336a96e42e8261b7313f23ee994e

bin/keystone-all

@@ -91,6 +91,13 @@ if __name__ == '__main__':
         sys.exit(1)
 
     monkeypatch_thread = not CONF.standard_threads
+    pydev_debug_url = utils.setup_remote_pydev_debug()
+    if pydev_debug_url:
+        # in order to work around errors caused by monkey patching we have to
+        # set the thread to False.  An explanation is here:
+        # http://lists.openstack.org/pipermail/openstack-dev/2012-August/
+        # 000794.html
+        monkeypatch_thread = False
     eventlet.patcher.monkey_patch(all=False, socket=True, time=True,
                                   thread=monkeypatch_thread)
 

keystone/common/utils.py

@@ -292,3 +292,22 @@ def hash_signed_token(signed_text):
     hash_ = hashlib.md5()
     hash_.update(signed_text)
     return hash_.hexdigest()
+
+
+def setup_remote_pydev_debug():
+    if CONF.pydev_debug_host and CONF.pydev_debug_port:
+        error_msg = ('Error setting up the debug environment.  Verify that the'
+                     ' option --debug-url has the format <host>:<port> and '
+                     'that a debugger processes is listening on that port.')
+
+        try:
+            from pydev import pydevd
+
+            pydevd.settrace(CONF.pydev_debug_host,
+                            port=CONF.pydev_debug_port,
+                            stdoutToServer=True,
+                            stderrToServer=True)
+            return True
+        except:
+            LOG.exception(_(error_msg))
+            raise

keystone/config.py

@@ -125,6 +125,9 @@ def register_cli_int(*args, **kw):
 
 register_cli_bool('standard-threads', default=False)
 
+register_cli_str('pydev-debug-host', default=None)
+register_cli_int('pydev-debug-port', default=None)
+
 register_str('admin_token', default='ADMIN')
 register_str('bind_host', default='0.0.0.0')
 register_str('compute_port', default=8774)