Updated import statements according to HACKING guidelines.

Added docstrings to each document.
Verified pep8 over all files.
Replaced some constants by enums accordingly. Still little bit more left in vm_util.py and vim_util.py files.

9 files changed, 112 insertions, 25 deletions

diff --git a/nova/virt/vmwareapi/__init__.py b/nova/virt/vmwareapi/__init__.py
index e9c06d96a..52e3ddf4d 100644
--- a/nova/virt/vmwareapi/__init__.py
+++ b/nova/virt/vmwareapi/__init__.py
@@ -14,3 +14,19 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
+
+"""
+:mod:`vmwareapi` -- Nova support for VMware ESX/ESXi Server through vSphere API
+===============================================================================
+"""
+
+
+class HelperBase(object):
+    """
+    The base for helper classes. This adds the VMwareAPI class attribute
+    """
+
+    VMwareAPI = None
+
+    def __init__(self):
+        return
diff --git a/nova/virt/vmwareapi/io_util.py b/nova/virt/vmwareapi/io_util.py
index 48ea4debf..3b3cbee33 100644
--- a/nova/virt/vmwareapi/io_util.py
+++ b/nova/virt/vmwareapi/io_util.py
@@ -16,15 +16,24 @@
 #    under the License.

 

 """

-    Reads a chunk from input file and writes the same to the output file till

-    it reaches the transferable size.

+Helper classes for multi-threaded I/O (read/write) in the basis of chunks.

+

+The class ThreadSafePipe queues the chunk data.

+

+The class IOThread reads chunks from input file and pipes it to output file

+till it reaches the transferable size

+

 """

 

-from Queue import Queue, Full, Empty

+from Queue import Empty

+from Queue import Full

+from Queue import Queue

 from threading import Thread

 import time

 import traceback

 

+THREAD_SLEEP_TIME = .01

+

 

 class ThreadSafePipe(Queue):

     """

@@ -122,12 +131,12 @@ class IOThread(Thread):
                         # no more data in read

                         break

                     #Restrict tight loop

-                    time.sleep(.01)

+                    time.sleep(THREAD_SLEEP_TIME)

                 except Full:

                     # Pipe full while writing to pipe - safe to retry since

                     #chunk is preserved

                     #Restrict tight loop

-                    time.sleep(.01)

+                    time.sleep(THREAD_SLEEP_TIME)

             if isinstance(self.output_file, ThreadSafePipe):

                 # If this is the reader thread, send eof signal

                 self.output_file.set_eof(True)

@@ -137,7 +146,7 @@ class IOThread(Thread):
                     raise IOError("Not enough data (%d of %d bytes)" \

                                 % (self.read_size, self.transfer_size))

 

-        except:

+        except Exception:

             self._error = True

             self._exception = str(traceback.format_exc())

         self._done = True

diff --git a/nova/virt/vmwareapi/read_write_util.py b/nova/virt/vmwareapi/read_write_util.py
index c3eeb0566..fcd95308a 100644
--- a/nova/virt/vmwareapi/read_write_util.py
+++ b/nova/virt/vmwareapi/read_write_util.py
@@ -15,6 +15,16 @@
 #    License for the specific language governing permissions and limitations

 #    under the License.

 

+""" Image file handlers

+

+Collection of classes to handle image upload/download to/from Image service

+(like Glance image storage and retrieval service) from/to ESX/ESXi server.

+

+Also a class is available that acts as Fake image service. It uses local

+file system for storage.

+

+"""

+

 import httplib

 import json

 import logging

@@ -84,7 +94,7 @@ class ImageServiceFile:
         """

         try:

             self.file_handle.close()

-        except:

+        except Exception:

             pass

 

     def get_image_properties(self):

@@ -267,7 +277,7 @@ class VMwareHTTPFile(object):
         """

         try:

             self.file_handle.close()

-        except:

+        except Exception:

             pass

 

     def __del__(self):

diff --git a/nova/virt/vmwareapi/vim.py b/nova/virt/vmwareapi/vim.py
index 03439a049..3007535dd 100644
--- a/nova/virt/vmwareapi/vim.py
+++ b/nova/virt/vmwareapi/vim.py
@@ -15,9 +15,15 @@
 #    License for the specific language governing permissions and limitations

 #    under the License.

 

-import ZSI

+"""

+Class facilitating SOAP calls to ESX/ESXi server

+

+"""

+

 import httplib

 

+import ZSI

+

 from nova.virt.vmwareapi import VimService_services

 

 RESP_NOT_XML_ERROR = 'Response is "text/html", not "text/xml'

diff --git a/nova/virt/vmwareapi/vim_util.py b/nova/virt/vmwareapi/vim_util.py
index 8596a1004..d38d8b949 100644
--- a/nova/virt/vmwareapi/vim_util.py
+++ b/nova/virt/vmwareapi/vim_util.py
@@ -17,7 +17,9 @@
 

 """

 The VMware API utility module

+

 """

+

 from nova.virt.vmwareapi.VimService_services_types import ns0

 

 MAX_CLONE_RETRIES = 1

diff --git a/nova/virt/vmwareapi/vm_util.py b/nova/virt/vmwareapi/vm_util.py
index 603537278..b1202f2b1 100644
--- a/nova/virt/vmwareapi/vm_util.py
+++ b/nova/virt/vmwareapi/vm_util.py
@@ -15,6 +15,11 @@
 #    License for the specific language governing permissions and limitations

 #    under the License.

 

+"""

+Utility functions to handle virtual disks, virtual network adapters, VMs etc.

+

+"""

+

 from nova.virt.vmwareapi.VimService_services_types import ns0

 

 

diff --git a/nova/virt/vmwareapi/vmops.py b/nova/virt/vmwareapi/vmops.py
index 23247a54e..4eda4ef0e 100644
--- a/nova/virt/vmwareapi/vmops.py
+++ b/nova/virt/vmwareapi/vmops.py
@@ -15,6 +15,10 @@
 #    License for the specific language governing permissions and limitations

 #    under the License.

 

+"""

+Class for VM tasks like spawn, snapshot, suspend, resume etc.

+

+"""

 import logging

 import os

 import time

@@ -23,7 +27,6 @@ import uuid
 from nova import db

 from nova import context

 from nova.compute import power_state

-

 from nova.virt.vmwareapi import vim_util

 from nova.virt.vmwareapi import vm_util

 from nova.virt.vmwareapi import vmware_images

@@ -102,8 +105,8 @@ class VMWareVMOps(object):
                 'but that already exists on the host' % instance.name)

         bridge = db.network_get_by_instance(context.get_admin_context(),

                                             instance['id'])['bridge']

-        #TODO: Shouldn't we consider any public network in case the network

-        #name supplied isn't there

+        #TODO(sateesh): Shouldn't we consider any public network in case

+        #the network name supplied isn't there

         network_ref = \

             self._get_network_with_the_name(bridge)

         if network_ref is None:

diff --git a/nova/virt/vmwareapi/vmware_images.py b/nova/virt/vmwareapi/vmware_images.py
index aa3b263cd..d3b1dc446 100644
--- a/nova/virt/vmwareapi/vmware_images.py
+++ b/nova/virt/vmwareapi/vmware_images.py
@@ -15,12 +15,16 @@
 #    License for the specific language governing permissions and limitations

 #    under the License.

 

-import time

-import os

+"""

+Utility functions to handle vm images. Also include fake image handlers.

+

+"""

+

 import logging

+import os

+import time

 

 from nova import flags

-

 from nova.virt.vmwareapi import read_write_util

 from nova.virt.vmwareapi import io_util

 

@@ -31,6 +35,7 @@ READ_CHUNKSIZE = 2 * 1024 * 1024
 WRITE_CHUNKSIZE = 2 * 1024 * 1024

 

 LOG = logging.getLogger("nova.virt.vmwareapi.vmware_images")

+TEST_IMAGE_PATH = "/tmp/vmware-test-images"

 

 

 def start_transfer(read_file_handle, write_file_handle, data_size):

@@ -148,7 +153,7 @@ def _get_fake_image(image, instance, **kwargs):
     """

     LOG.debug("Downloading image %s from fake image service" % image)

     image = str(image)

-    file_path = os.path.join("/tmp/vmware-test-images", image, image)

+    file_path = os.path.join(TEST_IMAGE_PATH, image, image)

     file_path = os.path.abspath(file_path)

     read_file_handle = read_write_util.FakeFileRead(file_path)

     file_size = read_file_handle.get_size()

@@ -215,9 +220,9 @@ def _put_fake_image(image, instance, **kwargs):
                                 kwargs.get("file_path"))

     file_size = read_file_handle.get_size()

     image = str(image)

-    image_dir_path = os.path.join("/tmp/vmware-test-images", image)

-    if not os.path.exists("/tmp/vmware-test-images"):

-        os.mkdir("/tmp/vmware-test-images")

+    image_dir_path = os.path.join(TEST_IMAGE_PATH, image)

+    if not os.path.exists(TEST_IMAGE_PATH):

+        os.mkdir(TEST_IMAGE_PATH)

         os.mkdir(image_dir_path)

     else:

         if not os.path.exists(image_dir_path):

@@ -247,7 +252,7 @@ def get_vmdk_size_and_properties(image, instance):
         raise NotImplementedError

     elif FLAGS.image_service == "nova.FakeImageService":

         image = str(image)

-        file_path = os.path.join("/tmp/vmware-test-images", image, image)

+        file_path = os.path.join(TEST_IMAGE_PATH, image, image)

         file_path = os.path.abspath(file_path)

         read_file_handle = read_write_util.FakeFileRead(file_path)

     size = read_file_handle.get_size()

diff --git a/nova/virt/vmwareapi_conn.py b/nova/virt/vmwareapi_conn.py
index d53a1c129..421efe91c 100644
--- a/nova/virt/vmwareapi_conn.py
+++ b/nova/virt/vmwareapi_conn.py
@@ -15,6 +15,23 @@
 #    License for the specific language governing permissions and limitations

 #    under the License.

 

+"""

+Connection class for VMware Infrastructure API in VMware ESX/ESXi platform

+

+Encapsulates the session management activties and acts as interface for VI API.

+The connection class sets up a session with the ESX/ESXi compute provider host

+and handles all the calls made to the host.

+

+**Related Flags**

+

+:vmwareapi_host_ip: IP of VMware ESX/ESXi compute provider host

+:vmwareapi_host_username: ESX/ESXi server user to be used for API session

+:vmwareapi_host_password: Password for the user "vmwareapi_host_username"

+:vmwareapi_task_poll_interval: The interval used for polling of remote tasks

+:vmwareapi_api_retry_count: Max number of retry attempts upon API failures

+

+"""

+

 import logging

 import time

 import urlparse

@@ -58,6 +75,19 @@ flags.DEFINE_float('vmwareapi_api_retry_count',
 TIME_BETWEEN_API_CALL_RETRIES = 2.0

 

 

+class TaskState:

+    """

+    Enumeration class for different states of task

+        0 - Task completed successfully

+        1 - Task is in queued state

+        2 - Task is in running state

+    """

+

+    TASK_SUCCESS = 0

+    TASK_QUEUED = 1

+    TASK_RUNNING = 2

+

+

 class Failure(Exception):

     """

     Base Exception class for handling task failures

@@ -278,7 +308,7 @@ class VMWareAPISession(object):
         # ESX host

         try:

             self.vim.Logout(self.vim.get_service_content().SessionManager)

-        except:

+        except Exception:

             pass

 

     def _call_method(self, module, method, *args, **kwargs):

@@ -363,17 +393,18 @@ class VMWareAPISession(object):
                 instance_id=int(instance_id),

                 action=task_name[0:255],

                 error=None)

-            if task_info.State in ['queued', 'running']:

+            if task_info.State in [TaskState.TASK_QUEUED,

+                                   TaskState.TASK_RUNNING]:

                 return

-            elif task_info.State == 'success':

+            elif task_info.State == TaskState.TASK_SUCCESS:

                 LOG.info("Task [%s] %s status: success " % (

                     task_name,

                     str(task_ref)))

-                done.send("success")

+                done.send(TaskState.TASK_SUCCESS)

             else:

                 error_info = str(task_info.Error.LocalizedMessage)

                 action["error"] = error_info

-                LOG.warn("Task [%s] %s status: error    %s" % (

+                LOG.warn("Task [%s] %s status: error [%s]" % (

                     task_name,

                     str(task_ref),

                     error_info))