From patchwork Tue Apr 13 15:55:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Snow X-Patchwork-Id: 12200865 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6225C433ED for ; Tue, 13 Apr 2021 15:57:43 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 39EEF60C40 for ; Tue, 13 Apr 2021 15:57:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 39EEF60C40 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43866 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lWLQ6-00037C-CF for qemu-devel@archiver.kernel.org; Tue, 13 Apr 2021 11:57:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38406) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lWLOb-0001RF-FW for qemu-devel@nongnu.org; Tue, 13 Apr 2021 11:56:09 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:58774) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lWLOX-00009E-4c for qemu-devel@nongnu.org; Tue, 13 Apr 2021 11:56:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618329362; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lkwW4qd7cXMVTa9AkNsmmBjla4GICLiyPDDcma8u0a4=; b=aD0IgotGpM+NIY5WdJ9QdvWNcwhlawfk3BanwMNjiyuey3/rl7/3g3iNkRSNi1YNP7TTuQ RXuoK/TIpINi8es7epWF0rzmuSBGXnZt1GcPy+LPUBh2XtuZ+nu2z/hKbVvLbedXrhXnh5 WsPermGeYmGI8sYx7PpYGE8IC5ouL38= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-157-9ulr9YSiPf-13uA4TPR50g-1; Tue, 13 Apr 2021 11:56:00 -0400 X-MC-Unique: 9ulr9YSiPf-13uA4TPR50g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 74F1B79EC6 for ; Tue, 13 Apr 2021 15:55:59 +0000 (UTC) Received: from scv.redhat.com (ovpn-117-61.rdu2.redhat.com [10.10.117.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id 990886A034; Tue, 13 Apr 2021 15:55:58 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org Subject: [PATCH RFC 1/7] util: asyncio-related helpers Date: Tue, 13 Apr 2021 11:55:47 -0400 Message-Id: <20210413155553.2660523-2-jsnow@redhat.com> In-Reply-To: <20210413155553.2660523-1-jsnow@redhat.com> References: <20210413155553.2660523-1-jsnow@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jsnow@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=jsnow@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: crosa@redhat.com, John Snow , ehabkost@redhat.com, stefanha@redhat.com, armbru@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Nothing too interesting design-wise here; mostly asyncio-related helpers designed to make writing Python 3.6-compliant code a little nicer to read. Signed-off-by: John Snow --- util.py | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 util.py diff --git a/util.py b/util.py new file mode 100644 index 0000000..2640f82 --- /dev/null +++ b/util.py @@ -0,0 +1,87 @@ +""" +Misc. utils and helper functions +""" + +import asyncio +import traceback +import sys +from typing import ( + Any, + Coroutine, + TypeVar, +) + + +T = TypeVar('T') + + +def create_task(coro: Coroutine[Any, Any, T]) -> 'asyncio.Future[T]': + """ + Python 3.6-compatible create_task() wrapper. + """ + if hasattr(asyncio, 'create_task'): + # Python 3.7+ + return asyncio.create_task(coro) + + # Python 3.6 + return asyncio.ensure_future(coro) + + +async def wait_closed(writer: asyncio.StreamWriter) -> None: + """ + Python 3.6-compatible StreamWriter.wait_closed() wrapper. + """ + if hasattr(writer, 'wait_closed'): + # Python 3.7+ + await writer.wait_closed() + else: + # Python 3.6 + transport = writer.transport + assert isinstance(transport, asyncio.WriteTransport) + + while not transport.is_closing(): + await asyncio.sleep(0.0) + while transport.get_write_buffer_size() > 0: + await asyncio.sleep(0.0) + + +def asyncio_run(coro: Coroutine[Any, Any, T]) -> T: + """ + Python 3.6-compatible asyncio.run() wrapper. + """ + # Python 3.7+ + if hasattr(asyncio, 'run'): + return asyncio.run(coro) + + # Python 3.6 + loop = asyncio.get_event_loop() + ret = loop.run_until_complete(coro) + loop.close() + + return ret + + +def pretty_traceback() -> str: + """ + Print the current traceback, but indented to provide visual distinction. + + This is useful for printing a traceback within a traceback for + debugging purposes when encapsulating errors to deliver them up the + stack; when those errors are printed, this helps provide a nice + visual grouping to quickly identify the parts of the error that + belong to the inner exception. + + :returns: A string, formatted something like the following:: + + | Traceback (most recent call last): + | File "foobar.py", line 42, in arbitrary_example + | foo.baz() + | ArbitraryError: [Errno 42] Something bad happened! + + """ + exc_lines = [] + for chunk in traceback.format_exception(*sys.exc_info()): + for line in chunk.split("\n"): + if line: + exc_lines.append(f" | {line}") + return "\n".join(exc_lines)