[libvirt] [PATCH python] libvirtaio: Fix compat with python 3.7
In python 3.7, async is now a keyword, so this throws a syntax error: File "/usr/lib64/python3.7/site-packages/libvirtaio.py", line 49 from asyncio import async as ensure_future ^ SyntaxError: invalid syntax Switch to getattr trickery to accomplish the same goal Signed-off-by: Cole Robinson <crobinso@redhat.com> --- libvirtaio.py | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) If we don't care about python3 < 3.4.4 compat, we can just do from asyncio import ensure_future diff --git a/libvirtaio.py b/libvirtaio.py index 1c432dd..9d517e6 100644 --- a/libvirtaio.py +++ b/libvirtaio.py @@ -43,10 +43,12 @@ import warnings import libvirt -try: - from asyncio import ensure_future -except ImportError: - from asyncio import async as ensure_future +# python < 3.4.4: we want 'async' +# python >= 3.4.4 < 3.7, we want 'ensure_future' +# python >= 3.7, 'async' is a reserved keyword, so we can't import it +ensure_future = getattr(asyncio, "ensure_future", None) +if not ensure_future: + ensure_future = getattr(asyncio, "async") class Callback(object): -- 2.17.1
On 06/25/2018 02:35 PM, Cole Robinson wrote:
In python 3.7, async is now a keyword, so this throws a syntax error:
File "/usr/lib64/python3.7/site-packages/libvirtaio.py", line 49 from asyncio import async as ensure_future ^ SyntaxError: invalid syntax
Switch to getattr trickery to accomplish the same goal
Signed-off-by: Cole Robinson <crobinso@redhat.com> --- libvirtaio.py | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
If we don't care about python3 < 3.4.4 compat, we can just do
from asyncio import ensure_future
Also I meant to say, this was prompted by python3.7 rebase in Fedora: https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/...
On Mon, 2018-06-25 at 14:35 -0400, Cole Robinson wrote:
If we don't care about python3 < 3.4.4 compat, we can just do
from asyncio import ensure_future
Debian 8, which is still a supported target platform[1], only has Python 3.4.2. [1] At least for libvirt; I'm going to assume libvirt-python doesn't have its own support policy. -- Andrea Bolognani / Red Hat / Virtualization
On Mon, Jun 25, 2018 at 02:35:28PM -0400, Cole Robinson wrote:
In python 3.7, async is now a keyword, so this throws a syntax error:
File "/usr/lib64/python3.7/site-packages/libvirtaio.py", line 49 from asyncio import async as ensure_future ^ SyntaxError: invalid syntax
Switch to getattr trickery to accomplish the same goal
Signed-off-by: Cole Robinson <crobinso@redhat.com> --- libvirtaio.py | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
If we don't care about python3 < 3.4.4 compat, we can just do
from asyncio import ensure_future
diff --git a/libvirtaio.py b/libvirtaio.py index 1c432dd..9d517e6 100644 --- a/libvirtaio.py +++ b/libvirtaio.py @@ -43,10 +43,12 @@ import warnings
import libvirt
-try: - from asyncio import ensure_future -except ImportError: - from asyncio import async as ensure_future +# python < 3.4.4: we want 'async' +# python >= 3.4.4 < 3.7, we want 'ensure_future'
This is slightly misleading, I would remove the ' < 3.7' part as we need 'ensure_future' even for that versions. The following explanation is good enough.
+# python >= 3.7, 'async' is a reserved keyword, so we can't import it +ensure_future = getattr(asyncio, "ensure_future", None) +if not ensure_future: + ensure_future = getattr(asyncio, "async")
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
On Mon, 2018-06-25 at 14:35 -0400, Cole Robinson wrote: [...]
-try: - from asyncio import ensure_future -except ImportError: - from asyncio import async as ensure_future +# python < 3.4.4: we want 'async' +# python >= 3.4.4 < 3.7, we want 'ensure_future' +# python >= 3.7, 'async' is a reserved keyword, so we can't import it +ensure_future = getattr(asyncio, "ensure_future", None) +if not ensure_future: + ensure_future = getattr(asyncio, "async")
Python is not exactly my forte, but the above makes sense to me and it stood up to some testing across all platforms supported by libvirt, so Reviewed-by: Andrea Bolognani <abologna@redhat.com> One nit is that the comment above the code doesn't IMHO describe the situation properly: I would have worded it along the lines of # Python < 3.4.4 doesn't have 'ensure_future', so we have to fall # back to 'async'; however, since 'async' is a reserved keyword # in Python >= 3.7, we can't perform a straightforward import and # we have to resort to getattr() instead I leave it up to you whether or not you want to reword the comment. -- Andrea Bolognani / Red Hat / Virtualization
On 06/27/2018 07:50 AM, Andrea Bolognani wrote:
On Mon, 2018-06-25 at 14:35 -0400, Cole Robinson wrote: [...]
-try: - from asyncio import ensure_future -except ImportError: - from asyncio import async as ensure_future +# python < 3.4.4: we want 'async' +# python >= 3.4.4 < 3.7, we want 'ensure_future' +# python >= 3.7, 'async' is a reserved keyword, so we can't import it +ensure_future = getattr(asyncio, "ensure_future", None) +if not ensure_future: + ensure_future = getattr(asyncio, "async")
Python is not exactly my forte, but the above makes sense to me and it stood up to some testing across all platforms supported by libvirt, so
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
One nit is that the comment above the code doesn't IMHO describe the situation properly: I would have worded it along the lines of
# Python < 3.4.4 doesn't have 'ensure_future', so we have to fall # back to 'async'; however, since 'async' is a reserved keyword # in Python >= 3.7, we can't perform a straightforward import and # we have to resort to getattr() instead
I leave it up to you whether or not you want to reword the comment.
I used your comment and pushed it now Thanks, Cole
participants (3)
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Andrea Bolognani -
Cole Robinson -
Pavel Hrdina