From 3f56b1f3ef971d4e6123c54fdac23654bfd65cca Mon Sep 17 00:00:00 2001
From: Kefu Chai <kchai@redhat.com>
Date: Sun, 27 Oct 2019 10:00:01 +0800
Subject: [PATCH] mgr/diskprediction_cloud: refactor timeout() decorator

* timeout() is never passed any parameter when being called, so let's
  remove the parameters list of "seconds" and "error_message"
* use `getattr()` instead of `hasattr()` for retrieving the
  member variable of `self`
* pass `self` to wrapper function explicitly.
* return `func()` right away.
* hardwire the error message of `TimeoutError` to "Timer expired",
  because
  - as neither errno.ETIME nor errno.ETIMEOUT is portable
  - the only caller of `TimeoutError` is `timeout()`, so there is
    no need to have the flexibility to pass a different error message
* use `wraps()` as a decorator, simpler this way.

Signed-off-by: Kefu Chai <kchai@redhat.com>
---
 .../diskprediction_cloud/agent/__init__.py    |  4 +--
 .../diskprediction_cloud/common/__init__.py   | 32 +++++++++----------
 2 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/src/pybind/mgr/diskprediction_cloud/agent/__init__.py b/src/pybind/mgr/diskprediction_cloud/agent/__init__.py
index c7702e5242c..e7e0ddcb6ed 100644
--- a/src/pybind/mgr/diskprediction_cloud/agent/__init__.py
+++ b/src/pybind/mgr/diskprediction_cloud/agent/__init__.py
@@ -29,10 +29,10 @@ class BaseAgent(object):
         else:
             return True
 
-    @timeout()
+    @timeout
     def _run(self):
         pass
 
-    @timeout()
+    @timeout
     def _collect_data(self):
         pass
diff --git a/src/pybind/mgr/diskprediction_cloud/common/__init__.py b/src/pybind/mgr/diskprediction_cloud/common/__init__.py
index ce5131b8f2b..be409416639 100644
--- a/src/pybind/mgr/diskprediction_cloud/common/__init__.py
+++ b/src/pybind/mgr/diskprediction_cloud/common/__init__.py
@@ -26,28 +26,26 @@ class DummyResonse:
 
 
 class TimeoutError(Exception):
-    pass
+    def __init__(self):
+        super(TimeoutError, self).__init__("Timer expired")
 
 
-def timeout(seconds=10, error_message=os.strerror(errno.ETIME)):
-    def decorator(func):
-        def _handle_timeout(signum, frame):
-            raise TimeoutError(error_message)
+def timeout(func):
+    DEFAULT_TIMEOUT = 10
 
-        def wrapper(*args, **kwargs):
-            if hasattr(args[0], '_timeout') is not None:
-                seconds = args[0]._timeout
-            signal.signal(signal.SIGALRM, _handle_timeout)
-            signal.alarm(seconds)
-            try:
-                result = func(*args, **kwargs)
-            finally:
-                signal.alarm(0)
-            return result
+    def _handle_timeout(signum, frame):
+        raise TimeoutError()
 
-        return wraps(func)(wrapper)
+    @wraps(func)
+    def wrapper(self):
+        signal.signal(signal.SIGALRM, _handle_timeout)
+        signal.alarm(getattr(self, '_timeout', DEFAULT_TIMEOUT))
+        try:
+            return func(self)
+        finally:
+            signal.alarm(0)
 
-    return decorator
+    return wrapper
 
 
 def get_human_readable(size, precision=2):
-- 
2.47.3