Question

我有一个基于GUI的项目。我希望将它扩展到代码本身和GUI部分。

这是我的代码： Main.py：

class NewerVersionWarning(Exception):
    def __init__(self, newest, current=__version__):
        self.newest = newest
        self.current = current
    def __str__(self):
        return "Version v%s is the latest version. You have v%s." % (self.newest, self.current)

class NoResultsException(Exception):
    pass

# ... and so on
def sanity_check():
    "Sanity Check for script."
    try:
        newest_version = WebParser.WebServices.get_newestversion()
        if newest_version > float(__version__):
            raise NewerVersionWarning(newest_version)
    except IOError as e:
        log.error("Could not check for the newest version (%s)" % str(e))

    if utils.get_free_space(config.temp_dir) < 200*1024**2: # 200 MB
        drive = os.path.splitdrive(config.temp_dir)[0]
        raise NoSpaceWarning(drive, utils.get_free_space(config.temp_dir))

# ... and so on

现在，在GUI部分，我只是在try-except块中调用该函数：

    try:
        Main.sanity_check()
    except NoSpaceWarning, e:
        s = tr("There are less than 200MB available in drive %s (%.2fMB left). Application may not function properly.") % (e.drive, e.space/1024.0**2)
        log.warning(s)
        QtGui.QMessageBox.warning(self, tr("Warning"), s, QtGui.QMessageBox.Ok)
    except NewerVersionWarning, e:
        log.warning("A new version of iQuality is available (%s)." % e.newest)
        QtGui.QMessageBox.information(self, tr("Information"), tr("A new version of iQuality is available (%s). Updates includes performance enhancements, bug fixes, new features and fixed parsers.<br /><br />You can grab it from the bottom box of the main window, or from the <a href=\"%s\">iQuality website</a>.") % (e.newest, config.website), QtGui.QMessageBox.Ok)

在当前设计中，检查在第一个警告/异常时停止。当然，异常应该停止代码，但是警告应该只向用户显示消息并在之后继续。我怎样才能这样设计？

Answer 1

也许你应该查看Python的warning mechanism。

它应该允许您在不停止程序的情况下警告用户危险情况。

Answer 2

尽管python提供了一种警告机制，但我觉得这样做更容易：

使用Warning类的子类警告。
使用_warnings列表并附加所有警告。

返回_warnings并在外部代码处理它：

try:
    _warnings = Main.sanity_check()
except CustomException1, e:
    # handle exception
except CustomException2, e:
    # handle exception

for w in _warnings:
    if isinstance(w, NoSpaceWarning):
        pass # handle warning
    if isinstance(w, NewerVersionWarning):
        pass # handle warning

设计一个健全性检查

2 个答案: