Merge remote-tracking branch 'origin/asyncio' into register-returns-last-transaction

Conflicts:
	CHANGES.rst

.travis.yml

 language: python
 sudo: false
+cache:
+  pip
+  directories:
+    - eggs
 matrix:
     include:
         - os: linux
@@ -24,9 +28,8 @@ matrix:
           python: 3.5
           env: ZEO4_SERVER=1
 install:
-    - pip install -U setuptools
-    - python bootstrap.py
-    - bin/buildout
+    - pip install -U zc.buildout
+    - buildout
 script:
     - bin/test -v1j99
 notifications:

CHANGES.rst

@@ -5,6 +5,14 @@ Changelog
   transaction, allowing the client to avoid an extra round trip during
   cache verification.
 
+- Client disconnect errors are now transient errors.  When
+  applications retry jobs that raise transient errors, jobs (e.g. web
+  requests) with disconnect errors will be retried. Together with
+  blocking synchronous ZEO server calls for a limited time while
+  disconnected, this change should allow brief disconnections due to
+  server restart to avoid generating client-visible errors (e.g. 500
+  web responses).
+
 - Fixed bugs in using the ZEO 5 client with ZEO 4 servers.
 
 5.0.0a2 (2016-07-30)

README.rst

@@ -180,12 +180,10 @@ Which is a short-hand for::
   connection = db.open()
 
 If you exit the Python process, the storage exits as well, as it's run
-in an in-process thread.  It will leave behind it's configuration and
-log file.  This provides a handy way to get a configuration example.
+in an in-process thread.
 
 You shut down the server more cleanly by calling the stop function
-returned by the ``ZEO.server`` function.  This will remove the
-temporary configuration file.
+returned by the ``ZEO.server`` function.
 
 To have data stored persistently, you can specify a file-storage path
 name using a ``path`` parameter.  If you want blob support, you can

src/ZEO/Exceptions.py

@@ -13,19 +13,26 @@
 ##############################################################################
 """Exceptions for ZEO."""
 
+import transaction.interfaces
+
 from ZODB.POSException import StorageError
 
 class ClientStorageError(StorageError):
-    """An error occurred in the ZEO Client Storage."""
+    """An error occurred in the ZEO Client Storage.
+    """
 
 class UnrecognizedResult(ClientStorageError):
-    """A server call returned an unrecognized result."""
+    """A server call returned an unrecognized result.
+    """
 
-class ClientDisconnected(ClientStorageError):
-    """The database storage is disconnected from the storage."""
+class ClientDisconnected(ClientStorageError,
+                         transaction.interfaces.TransientError):
+    """The database storage is disconnected from the storage.
+    """
 
 class AuthError(StorageError):
-    """The client provided invalid authentication credentials."""
+    """The client provided invalid authentication credentials.
+    """
 
 class ProtocolError(ClientStorageError):
     """A client contacted a server with an incomparible protocol

src/ZEO/tests/forker.py

@@ -139,6 +139,7 @@ def runner(config, qin, qout, timeout=None,
             )
         thread.setDaemon(True)
         thread.start()
+        os.remove(config)
 
         try:
             qin.get(timeout=timeout) # wait for shutdown
@@ -181,7 +182,6 @@ def stop_runner(thread, config, qin, qout, stop_timeout=9, pid=None):
             gc.collect()
 
     thread.join(stop_timeout)
-    os.remove(config)
 
 def start_zeo_server(storage_conf=None, zeo_conf=None, port=None, keep=False,
                      path='Data.fs', protocol=None, blob_dir=None,

src/ZEO/tests/testZEO.py

@@ -1412,6 +1412,14 @@ call to the server. we'd get some sort of error here.
 
 
 
+    """
+
+def ClientDisconnected_errors_are_TransientErrors():
+    """
+    >>> from ZEO.Exceptions import ClientDisconnected
+    >>> from transaction.interfaces import TransientError
+    >>> issubclass(ClientDisconnected, TransientError)
+    True
     """
 
 if sys.platform.startswith('win'):