Merge "hyper-v: Converts all os-win exceptions"

1 files changed, 43 insertions, 33 deletions

diff --git a/ceilometer/compute/virt/hyperv/inspector.py b/ceilometer/compute/virt/hyperv/inspector.py
index f1819f22..3d4fcb42 100644
--- a/ceilometer/compute/virt/hyperv/inspector.py
+++ b/ceilometer/compute/virt/hyperv/inspector.py
@@ -26,39 +26,45 @@ from ceilometer.compute.pollsters import util
 from ceilometer.compute.virt import inspector as virt_inspector
 
 
-def convert_exceptions(function, exception_map):
+def convert_exceptions(exception_map, yields=True):
     expected_exceptions = tuple(exception_map.keys())
 
-    @functools.wraps(function)
-    def wrapper(*args, **kwargs):
-        try:
-            return function(*args, **kwargs)
-        except expected_exceptions as ex:
-            # exception might be a subclass of an expected exception.
-            for expected in expected_exceptions:
-                if isinstance(ex, expected):
-                    raised_exception = exception_map[expected]
-                    break
-
-            exc_info = sys.exc_info()
-            # NOTE(claudiub): Python 3 raises the exception object given as
-            # the second argument in six.reraise.
-            # The original message will be maintained by passing the original
-            # exception.
-            exc = raised_exception(six.text_type(exc_info[1]))
-            six.reraise(raised_exception, exc, exc_info[2])
-    return wrapper
-
-
-def decorate_all_methods(decorator, *args, **kwargs):
-    def decorate(cls):
-        for attr in cls.__dict__:
-            class_member = getattr(cls, attr)
-            if callable(class_member):
-                setattr(cls, attr, decorator(class_member, *args, **kwargs))
-        return cls
-
-    return decorate
+    def _reraise_exception(exc):
+        # exception might be a subclass of an expected exception.
+        for expected in expected_exceptions:
+            if isinstance(exc, expected):
+                raised_exception = exception_map[expected]
+                break
+
+        exc_info = sys.exc_info()
+        # NOTE(claudiub): Python 3 raises the exception object given as
+        # the second argument in six.reraise.
+        # The original message will be maintained by passing the
+        # original exception.
+        exc = raised_exception(six.text_type(exc_info[1]))
+        six.reraise(raised_exception, exc, exc_info[2])
+
+    def decorator(function):
+        if yields:
+            @functools.wraps(function)
+            def wrapper(*args, **kwargs):
+                try:
+                    # NOTE(claudiub): We're consuming the function's yield in
+                    # order to avoid yielding a generator.
+                    for item in function(*args, **kwargs):
+                        yield item
+                except expected_exceptions as ex:
+                    _reraise_exception(ex)
+        else:
+            @functools.wraps(function)
+            def wrapper(*args, **kwargs):
+                try:
+                    return function(*args, **kwargs)
+                except expected_exceptions as ex:
+                    _reraise_exception(ex)
+
+        return wrapper
+    return decorator
 
 
 exception_conversion_map = collections.OrderedDict([
@@ -69,12 +75,11 @@ exception_conversion_map = collections.OrderedDict([
     (os_win_exc.OSWinException, virt_inspector.InspectorException),
 ])
 
-# NOTE(claudiub): the purpose of the decorator below is to prevent any
+# NOTE(claudiub): the purpose of the decorators below is to prevent any
 # os_win exceptions (subclasses of OSWinException) to leak outside of the
 # HyperVInspector.
 
 
-@decorate_all_methods(convert_exceptions, exception_conversion_map)
 class HyperVInspector(virt_inspector.Inspector):
 
     def __init__(self, conf):
@@ -91,6 +96,7 @@ class HyperVInspector(virt_inspector.Inspector):
 
         return float(host_cpu_clock * host_cpu_count)
 
+    @convert_exceptions(exception_conversion_map, yields=False)
     def inspect_instance(self, instance, duration):
         instance_name = util.instance_name(instance)
         (cpu_clock_used,
@@ -105,6 +111,7 @@ class HyperVInspector(virt_inspector.Inspector):
             cpu_time=cpu_time,
             memory_usage=memory_usage)
 
+    @convert_exceptions(exception_conversion_map)
     def inspect_vnics(self, instance, duration):
         instance_name = util.instance_name(instance)
         for vnic_metrics in self._utils.get_vnic_metrics(instance_name):
@@ -122,6 +129,7 @@ class HyperVInspector(virt_inspector.Inspector):
                 tx_drop=0,
                 tx_errors=0)
 
+    @convert_exceptions(exception_conversion_map)
     def inspect_disks(self, instance, duration):
         instance_name = util.instance_name(instance)
         for disk_metrics in self._utils.get_disk_metrics(instance_name):
@@ -134,6 +142,7 @@ class HyperVInspector(virt_inspector.Inspector):
                 write_bytes=disk_metrics['write_mb'] * units.Mi,
                 errors=0, wr_total_times=0, rd_total_times=0)
 
+    @convert_exceptions(exception_conversion_map)
     def inspect_disk_latency(self, instance, duration):
         instance_name = util.instance_name(instance)
         for disk_metrics in self._utils.get_disk_latency_metrics(
@@ -142,6 +151,7 @@ class HyperVInspector(virt_inspector.Inspector):
                 device=disk_metrics['instance_id'],
                 disk_latency=disk_metrics['disk_latency'] / 1000)
 
+    @convert_exceptions(exception_conversion_map)
     def inspect_disk_iops(self, instance, duration):
         instance_name = util.instance_name(instance)
         for disk_metrics in self._utils.get_disk_iops_count(instance_name):