From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.6 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 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 0E7E4C11F67 for ; Thu, 1 Jul 2021 04:14:37 +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 7DCE261467 for ; Thu, 1 Jul 2021 04:14:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7DCE261467 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]:40736 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lyo5z-0002bl-KG for qemu-devel@archiver.kernel.org; Thu, 01 Jul 2021 00:14:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42280) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lyo4z-0008Gz-61 for qemu-devel@nongnu.org; Thu, 01 Jul 2021 00:13:33 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:20206) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lyo4u-0000co-Ry for qemu-devel@nongnu.org; Thu, 01 Jul 2021 00:13:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625112808; 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=u37O0ssgS4A0aLWMkEpMNTyBmETh8DDdyDuOTHgvjtg=; b=ds+KH2PasmcHi4gT/7/PGGo8E6cYR48V4qToUhfveNrm+OfQZCNiDB9Y1cTKrDvdqKQVJh y4cmTJbDDL+tzSnQd18rK1YQCgyDQkvDw5ks4cWi0dchbdRURN3z2A4sDx4jjz9JGQKSUi 28NxP+BD7rSazio6HXL62Hlbf2U4hBU= 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-506-xtBaVglIOHGtS0_UN-ZfMQ-1; Thu, 01 Jul 2021 00:13:27 -0400 X-MC-Unique: xtBaVglIOHGtS0_UN-ZfMQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 39EE2801F97; Thu, 1 Jul 2021 04:13:26 +0000 (UTC) Received: from scv.redhat.com (ovpn-118-71.rdu2.redhat.com [10.10.118.71]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3E88069CB4; Thu, 1 Jul 2021 04:13:25 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org Subject: [PATCH 04/20] python/aqmp: add error classes Date: Thu, 1 Jul 2021 00:12:57 -0400 Message-Id: <20210701041313.1696009-5-jsnow@redhat.com> In-Reply-To: <20210701041313.1696009-1-jsnow@redhat.com> References: <20210701041313.1696009-1-jsnow@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 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 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=170.10.133.124; envelope-from=jsnow@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.435, 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: Eduardo Habkost , Eric Blake , Stefan Hajnoczi , Markus Armbruster , Wainer dos Santos Moschetta , "Niteesh G . S ." , Willian Rampazzo , Cleber Rosa , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Signed-off-by: John Snow --- python/qemu/aqmp/__init__.py | 7 +++ python/qemu/aqmp/error.py | 97 ++++++++++++++++++++++++++++++++++++ 2 files changed, 104 insertions(+) create mode 100644 python/qemu/aqmp/error.py diff --git a/python/qemu/aqmp/__init__.py b/python/qemu/aqmp/__init__.py index 4c713b3ccf..8e955d784d 100644 --- a/python/qemu/aqmp/__init__.py +++ b/python/qemu/aqmp/__init__.py @@ -21,7 +21,14 @@ # This work is licensed under the terms of the GNU GPL, version 2. See # the COPYING file in the top-level directory. +from .error import AQMPError, MultiException + # The order of these fields impact the Sphinx documentation order. __all__ = ( + # Exceptions + 'AQMPError', + + # Niche topics + 'MultiException', ) diff --git a/python/qemu/aqmp/error.py b/python/qemu/aqmp/error.py new file mode 100644 index 0000000000..126f77bb5c --- /dev/null +++ b/python/qemu/aqmp/error.py @@ -0,0 +1,97 @@ +""" +AQMP Error Classes + +This package seeks to provide semantic error classes that are intended +to be used directly by clients when they would like to handle particular +semantic failures (e.g. "failed to connect") without needing to know the +enumeration of possible reasons for that failure. + +AQMPError serves as the ancestor for *almost* all exceptions raised by +this package, and is suitable for use in handling semantic errors from +this library. In most cases, individual public methods will attempt to +catch and re-encapsulate various exceptions to provide a semantic +error-handling interface. + +.. caution:: + + The only exception that is not an `AQMPError` is + `MultiException`. It is special, and used to encapsulate one-or-more + exceptions of an arbitrary kind; this exception MAY be raised on + `disconnect()` when there are two or more exceptions from the AQMP + event loop to report back to the caller. + + Every pain has been taken to prevent this circumstance but in + certain cases these exceptions may occasionally be (unfortunately) + visible. See `MultiException` and `AsyncProtocol.disconnect()` for + more details. + + +.. admonition:: AQMP Exception Hierarchy Reference + + | `Exception` + | +-- `MultiException` + | +-- `AQMPError` + | +-- `ConnectError` + | +-- `StateError` + | +-- `ExecInterruptedError` + | +-- `ExecuteError` + | +-- `ListenerError` + | +-- `ProtocolError` + | +-- `DeserializationError` + | +-- `UnexpectedTypeError` + | +-- `ServerParseError` + | +-- `BadReplyError` + | +-- `GreetingError` + | +-- `NegotiationError` +""" + +from typing import Iterable, Iterator, List + + +class AQMPError(Exception): + """Abstract error class for all errors originating from this package.""" + + +class ProtocolError(AQMPError): + """ + Abstract error class for protocol failures. + + Semantically, these errors are generally the fault of either the + protocol server or as a result of a bug in this this library. + + :param error_message: Human-readable string describing the error. + """ + def __init__(self, error_message: str): + super().__init__(error_message) + #: Human-readable error message, without any prefix. + self.error_message: str = error_message + + +class MultiException(Exception): + """ + Used for multiplexing exceptions. + + This exception is used in the case that errors were encountered in both the + Reader and Writer tasks, and we must raise more than one. + + PEP 0654 seeks to remedy this clunky infrastructure, but it will not be + available for quite some time -- possibly Python 3.11 or even later. + + :param exceptions: An iterable of `BaseException` objects. + """ + def __init__(self, exceptions: Iterable[BaseException]): + super().__init__(exceptions) + self._exceptions: List[BaseException] = list(exceptions) + + def __str__(self) -> str: + ret = "------------------------------\n" + ret += "Multiple Exceptions occurred:\n" + ret += "\n" + for i, exc in enumerate(self._exceptions): + ret += f"{i}) {str(exc)}\n" + ret += "\n" + ret += "-----------------------------\n" + return ret + + def __iter__(self) -> Iterator[BaseException]: + return iter(self._exceptions) -- 2.31.1