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<section id="policies">
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<span id="asyncio-policies"></span><h1>策略<a class="headerlink" href="#policies" title="永久链接至标题">¶</a></h1>
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<p>事件循环策略是各个进程的全局对象 ，它控制事件循环的管理。每个事件循环都有一个默认策略，可以使用策略API更改和定制该策略。</p>
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<p>策略定义了“上下文”的概念，每个上下文管理一个单独的事件循环。默认策略将*context*定义为当前线程。</p>
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<p>通过使用自定义事件循环策略，可以自定义 <a class="reference internal" href="asyncio-eventloop.html#asyncio.get_event_loop" title="asyncio.get_event_loop"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_event_loop()</span></code></a> 、 <a class="reference internal" href="asyncio-eventloop.html#asyncio.set_event_loop" title="asyncio.set_event_loop"><code class="xref py py-func docutils literal notranslate"><span class="pre">set_event_loop()</span></code></a> 和 <a class="reference internal" href="asyncio-eventloop.html#asyncio.new_event_loop" title="asyncio.new_event_loop"><code class="xref py py-func docutils literal notranslate"><span class="pre">new_event_loop()</span></code></a> 函数的行为。</p>
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<p>策略对象应该实现 <a class="reference internal" href="#asyncio.AbstractEventLoopPolicy" title="asyncio.AbstractEventLoopPolicy"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractEventLoopPolicy</span></code></a> 抽象基类中定义的API。</p>
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<section id="getting-and-setting-the-policy">
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<h2>获取和设置策略<a class="headerlink" href="#getting-and-setting-the-policy" title="永久链接至标题">¶</a></h2>
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<p>可以使用下面函数获取和设置当前进程的策略:</p>
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<dl class="function">
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<dt id="asyncio.get_event_loop_policy">
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<code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">get_event_loop_policy</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.get_event_loop_policy" title="永久链接至目标">¶</a></dt>
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<dd><p>返回当前进程域的策略。</p>
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</dd></dl>
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<dl class="function">
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<dt id="asyncio.set_event_loop_policy">
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<code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">set_event_loop_policy</code><span class="sig-paren">(</span><em class="sig-param">policy</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.set_event_loop_policy" title="永久链接至目标">¶</a></dt>
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<dd><p>将 <em>policy</em> 设置为当前进程域策略。</p>
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<p>如果 <em>policy</em> 设为 <code class="docutils literal notranslate"><span class="pre">None</span></code> 将恢复默认策略。</p>
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</dd></dl>
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</section>
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<section id="policy-objects">
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<h2>策略对象<a class="headerlink" href="#policy-objects" title="永久链接至标题">¶</a></h2>
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<p>抽象事件循环策略基类定义如下:</p>
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<dl class="class">
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<dt id="asyncio.AbstractEventLoopPolicy">
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<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">AbstractEventLoopPolicy</code><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy" title="永久链接至目标">¶</a></dt>
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<dd><p>异步策略的抽象基类。</p>
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<dl class="method">
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<dt id="asyncio.AbstractEventLoopPolicy.get_event_loop">
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<code class="sig-name descname">get_event_loop</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.get_event_loop" title="永久链接至目标">¶</a></dt>
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<dd><p>为当前上下文获取事件循环。</p>
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<p>返回一个实现 <a class="reference internal" href="asyncio-eventloop.html#asyncio.AbstractEventLoop" title="asyncio.AbstractEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractEventLoop</span></code></a> 接口的事件循环对象。</p>
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<p>该方法永远不应返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
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<div class="versionchanged">
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<p><span class="versionmodified changed">在 3.6 版更改.</span></p>
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</div>
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</dd></dl>
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<dl class="method">
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<dt id="asyncio.AbstractEventLoopPolicy.set_event_loop">
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<code class="sig-name descname">set_event_loop</code><span class="sig-paren">(</span><em class="sig-param">loop</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.set_event_loop" title="永久链接至目标">¶</a></dt>
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<dd><p>将当前上下文的事件循环设置为 <em>loop</em> 。</p>
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</dd></dl>
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<dl class="method">
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<dt id="asyncio.AbstractEventLoopPolicy.new_event_loop">
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<code class="sig-name descname">new_event_loop</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.new_event_loop" title="永久链接至目标">¶</a></dt>
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<dd><p>创建并返回一个新的事件循环对象。</p>
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<p>该方法永远不应返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
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</dd></dl>
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<dl class="method">
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<dt id="asyncio.AbstractEventLoopPolicy.get_child_watcher">
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<code class="sig-name descname">get_child_watcher</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.get_child_watcher" title="永久链接至目标">¶</a></dt>
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<dd><p>获取子进程监视器对象。</p>
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<p>返回一个实现 <a class="reference internal" href="#asyncio.AbstractChildWatcher" title="asyncio.AbstractChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractChildWatcher</span></code></a> 接口的监视器对象。</p>
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<p>该函数仅支持Unix。</p>
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</dd></dl>
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<dl class="method">
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<dt id="asyncio.AbstractEventLoopPolicy.set_child_watcher">
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<code class="sig-name descname">set_child_watcher</code><span class="sig-paren">(</span><em class="sig-param">watcher</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.set_child_watcher" title="永久链接至目标">¶</a></dt>
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<dd><p>将当前子进程监视器设置为 <em>watcher</em> 。</p>
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<p>该函数仅支持Unix。</p>
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</dd></dl>
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</dd></dl>
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<p>asyncio附带下列内置策略:</p>
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<dl class="class">
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<dt id="asyncio.DefaultEventLoopPolicy">
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<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">DefaultEventLoopPolicy</code><a class="headerlink" href="#asyncio.DefaultEventLoopPolicy" title="永久链接至目标">¶</a></dt>
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<dd><p>默认的 asyncio 策略。 在 Unix 上使用 <a class="reference internal" href="asyncio-eventloop.html#asyncio.SelectorEventLoop" title="asyncio.SelectorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">SelectorEventLoop</span></code></a> 而在 Windows 上使用 <a class="reference internal" href="asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a>。</p>
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<p>不需要手动安装默认策略。asyncio已配置成自动使用默认策略。</p>
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<div class="versionchanged">
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<p><span class="versionmodified changed">在 3.8 版更改: </span>在 Windows 上，现在默认会使用 <a class="reference internal" href="asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a>。</p>
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</div>
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</dd></dl>
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<dl class="class">
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<dt id="asyncio.WindowsSelectorEventLoopPolicy">
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<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">WindowsSelectorEventLoopPolicy</code><a class="headerlink" href="#asyncio.WindowsSelectorEventLoopPolicy" title="永久链接至目标">¶</a></dt>
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<dd><p>一个使用 <a class="reference internal" href="asyncio-eventloop.html#asyncio.SelectorEventLoop" title="asyncio.SelectorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">SelectorEventLoop</span></code></a> 事件循环实现的替代事件循环策略。</p>
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<p class="availability"><a class="reference internal" href="intro.html#availability"><span class="std std-ref">可用性</span></a>: Windows。</p>
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</dd></dl>
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|
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<dl class="class">
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<dt id="asyncio.WindowsProactorEventLoopPolicy">
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<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">WindowsProactorEventLoopPolicy</code><a class="headerlink" href="#asyncio.WindowsProactorEventLoopPolicy" title="永久链接至目标">¶</a></dt>
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<dd><p>使用 <a class="reference internal" href="asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a> 事件循环实现的另一种事件循环策略。</p>
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<p class="availability"><a class="reference internal" href="intro.html#availability"><span class="std std-ref">可用性</span></a>: Windows。</p>
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</dd></dl>
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</section>
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<section id="process-watchers">
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<span id="asyncio-watchers"></span><h2>进程监视器<a class="headerlink" href="#process-watchers" title="永久链接至标题">¶</a></h2>
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<p>进程监视器允许定制事件循环如何监视Unix子进程。具体来说，事件循环需要知道子进程何时退出。</p>
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<p>在asyncio中子进程由 <a class="reference internal" href="asyncio-subprocess.html#asyncio.create_subprocess_exec" title="asyncio.create_subprocess_exec"><code class="xref py py-func docutils literal notranslate"><span class="pre">create_subprocess_exec()</span></code></a> 和 <a class="reference internal" href="asyncio-eventloop.html#asyncio.loop.subprocess_exec" title="asyncio.loop.subprocess_exec"><code class="xref py py-meth docutils literal notranslate"><span class="pre">loop.subprocess_exec()</span></code></a> 函数创建。</p>
|
||
<p>asyncio 定义了 <a class="reference internal" href="#asyncio.AbstractChildWatcher" title="asyncio.AbstractChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractChildWatcher</span></code></a> 抽象基类，子监视器必须要实现它，并具有四种不同实现: <a class="reference internal" href="#asyncio.ThreadedChildWatcher" title="asyncio.ThreadedChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">ThreadedChildWatcher</span></code></a> (已配置为默认使用), <a class="reference internal" href="#asyncio.MultiLoopChildWatcher" title="asyncio.MultiLoopChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">MultiLoopChildWatcher</span></code></a>, <a class="reference internal" href="#asyncio.SafeChildWatcher" title="asyncio.SafeChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">SafeChildWatcher</span></code></a> 和 <a class="reference internal" href="#asyncio.FastChildWatcher" title="asyncio.FastChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">FastChildWatcher</span></code></a>。</p>
|
||
<p>请参阅 <a class="reference internal" href="asyncio-subprocess.html#asyncio-subprocess-threads"><span class="std std-ref">子进程和线程</span></a> 部分。</p>
|
||
<p>以下两个函数可用于自定义子进程监视器实现，它将被asyncio事件循环使用:</p>
|
||
<dl class="function">
|
||
<dt id="asyncio.get_child_watcher">
|
||
<code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">get_child_watcher</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.get_child_watcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回当前策略的当前子监视器。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="asyncio.set_child_watcher">
|
||
<code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">set_child_watcher</code><span class="sig-paren">(</span><em class="sig-param">watcher</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.set_child_watcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>将当前策略的子监视器设置为 <em>watcher</em> 。<em>watcher</em> 必须实现 <a class="reference internal" href="#asyncio.AbstractChildWatcher" title="asyncio.AbstractChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractChildWatcher</span></code></a> 基类定义的方法。</p>
|
||
</dd></dl>
|
||
|
||
<div class="admonition note">
|
||
<p class="admonition-title">注解</p>
|
||
<p>第三方事件循环实现可能不支持自定义子监视器。对于这样的事件循环，禁止使用 <a class="reference internal" href="#asyncio.set_child_watcher" title="asyncio.set_child_watcher"><code class="xref py py-func docutils literal notranslate"><span class="pre">set_child_watcher()</span></code></a> 或不起作用。</p>
|
||
</div>
|
||
<dl class="class">
|
||
<dt id="asyncio.AbstractChildWatcher">
|
||
<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">AbstractChildWatcher</code><a class="headerlink" href="#asyncio.AbstractChildWatcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><dl class="method">
|
||
<dt id="asyncio.AbstractChildWatcher.add_child_handler">
|
||
<code class="sig-name descname">add_child_handler</code><span class="sig-paren">(</span><em class="sig-param">pid</em>, <em class="sig-param">callback</em>, <em class="sig-param">*args</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractChildWatcher.add_child_handler" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>注册一个新的子处理回调函数。</p>
|
||
<p>安排 <code class="docutils literal notranslate"><span class="pre">callback(pid,</span> <span class="pre">returncode,</span> <span class="pre">*args)</span></code> 在进程的PID与 <em>pid</em> 相等时调用。指定另一个同进程的回调函数替换之前的回调处理函数。</p>
|
||
<p>回调函数 <em>callback</em> 必须是线程安全。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="asyncio.AbstractChildWatcher.remove_child_handler">
|
||
<code class="sig-name descname">remove_child_handler</code><span class="sig-paren">(</span><em class="sig-param">pid</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractChildWatcher.remove_child_handler" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>删除进程PID与 <em>pid</em> 相等的进程的处理函数。</p>
|
||
<p>处理函数成功删除时返回 <code class="docutils literal notranslate"><span class="pre">True</span></code> ，没有删除时返回 <code class="docutils literal notranslate"><span class="pre">False</span></code> 。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="asyncio.AbstractChildWatcher.attach_loop">
|
||
<code class="sig-name descname">attach_loop</code><span class="sig-paren">(</span><em class="sig-param">loop</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractChildWatcher.attach_loop" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>给一个事件循环绑定监视器。</p>
|
||
<p>如果监视器之前已绑定另一个事件循环，那么在绑定新循环前会先解绑原来的事件循环。</p>
|
||
<p>注意：循环有可能是 <code class="docutils literal notranslate"><span class="pre">None</span></code> 。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="asyncio.AbstractChildWatcher.is_active">
|
||
<code class="sig-name descname">is_active</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractChildWatcher.is_active" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果监视器已准备好使用则返回 <code class="docutils literal notranslate"><span class="pre">True</span></code>。</p>
|
||
<p>使用 <em>不活动的</em> 当前子监视器生成子进程将引发 <a class="reference internal" href="exceptions.html#RuntimeError" title="RuntimeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">RuntimeError</span></code></a>。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.8 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="asyncio.AbstractChildWatcher.close">
|
||
<code class="sig-name descname">close</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractChildWatcher.close" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>关闭监视器。</p>
|
||
<p>必须调用这个方法以确保相关资源会被清理。</p>
|
||
</dd></dl>
|
||
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt id="asyncio.ThreadedChildWatcher">
|
||
<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">ThreadedChildWatcher</code><a class="headerlink" href="#asyncio.ThreadedChildWatcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>此实现会为每个生成的子进程启动一具新的等待线程。</p>
|
||
<p>即使是当 asyncio 事件循环运行在非主 OS 线程上时它也能可靠地工作。</p>
|
||
<p>当处理大量子进程时不存在显著的开销 (每次子进程结束时为 <em>O(1)</em>)，但当每个进程启动一个线程时则需要额外的内存。</p>
|
||
<p>此监视器会默认被使用。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.8 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt id="asyncio.MultiLoopChildWatcher">
|
||
<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">MultiLoopChildWatcher</code><a class="headerlink" href="#asyncio.MultiLoopChildWatcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>此实现会在实例化时注册一个 <code class="xref py py-data docutils literal notranslate"><span class="pre">SIGCHLD</span></code> 信号处理程序。 这可能会破坏为 <code class="xref py py-data docutils literal notranslate"><span class="pre">SIGCHLD</span></code> 信号安装自定义处理程序的第三方代码。</p>
|
||
<p>此监视器会在收到 <code class="xref py py-data docutils literal notranslate"><span class="pre">SIGCHLD</span></code> 信号时通过显式地轮询每个进程来避免干扰其他代码生成的进程。</p>
|
||
<p>该监视器一旦被安装就不会限制从不同线程运行子进程。</p>
|
||
<p>该解决方案是安全的，但在处理大量进程时会有显著的开销 (每收到一个 <code class="xref py py-data docutils literal notranslate"><span class="pre">SIGCHLD</span></code> 时为 <em>O(n)</em>)。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.8 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt id="asyncio.SafeChildWatcher">
|
||
<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">SafeChildWatcher</code><a class="headerlink" href="#asyncio.SafeChildWatcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>该实现会使用主线程中的活动事件循环来处理 <code class="xref py py-data docutils literal notranslate"><span class="pre">SIGCHLD</span></code> 信号。 如果主线程没有正在运行的事件循环，则其他线程无法生成子进程 (会引发 <a class="reference internal" href="exceptions.html#RuntimeError" title="RuntimeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">RuntimeError</span></code></a>)。</p>
|
||
<p>此监视器会在收到 <code class="xref py py-data docutils literal notranslate"><span class="pre">SIGCHLD</span></code> 信号时通过显式地轮询每个进程来避免干扰其他代码生成的进程。</p>
|
||
<p>该解决方案与 <a class="reference internal" href="#asyncio.MultiLoopChildWatcher" title="asyncio.MultiLoopChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">MultiLoopChildWatcher</span></code></a> 同样安全并同样具有 <em>O(N)</em> 复杂度，但需要主线程有正在运行的事件循环才能工作。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt id="asyncio.FastChildWatcher">
|
||
<em class="property">class </em><code class="sig-prename descclassname">asyncio.</code><code class="sig-name descname">FastChildWatcher</code><a class="headerlink" href="#asyncio.FastChildWatcher" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>这种实现直接调用 <code class="docutils literal notranslate"><span class="pre">os.waitpid(-1)</span></code> 来获取所有已结束的进程，可能会中断其它代码洐生进程并等待它们结束。</p>
|
||
<p>在处理大量子监视器时没有明显的开销( <em>O(1)</em> 每次子监视器结束)。</p>
|
||
<p>该解决方案需要主线程有正在运行的事件循环才能工作，这与 <a class="reference internal" href="#asyncio.SafeChildWatcher" title="asyncio.SafeChildWatcher"><code class="xref py py-class docutils literal notranslate"><span class="pre">SafeChildWatcher</span></code></a> 一样。</p>
|
||
</dd></dl>
|
||
|
||
</section>
|
||
<section id="custom-policies">
|
||
<h2>自定义策略<a class="headerlink" href="#custom-policies" title="永久链接至标题">¶</a></h2>
|
||
<p>要实现一个新的事件循环策略，建议子类化 <a class="reference internal" href="#asyncio.DefaultEventLoopPolicy" title="asyncio.DefaultEventLoopPolicy"><code class="xref py py-class docutils literal notranslate"><span class="pre">DefaultEventLoopPolicy</span></code></a> 并重写需要定制行为的方法，例如:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">MyEventLoopPolicy</span><span class="p">(</span><span class="n">asyncio</span><span class="o">.</span><span class="n">DefaultEventLoopPolicy</span><span class="p">):</span>
|
||
|
||
<span class="k">def</span> <span class="nf">get_event_loop</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
||
<span class="w"> </span><span class="sd">"""Get the event loop.</span>
|
||
|
||
<span class="sd"> This may be None or an instance of EventLoop.</span>
|
||
<span class="sd"> """</span>
|
||
<span class="n">loop</span> <span class="o">=</span> <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="n">get_event_loop</span><span class="p">()</span>
|
||
<span class="c1"># Do something with loop ...</span>
|
||
<span class="k">return</span> <span class="n">loop</span>
|
||
|
||
<span class="n">asyncio</span><span class="o">.</span><span class="n">set_event_loop_policy</span><span class="p">(</span><span class="n">MyEventLoopPolicy</span><span class="p">())</span>
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
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|
||
<li><a class="reference internal" href="#">策略</a><ul>
|
||
<li><a class="reference internal" href="#getting-and-setting-the-policy">获取和设置策略</a></li>
|
||
<li><a class="reference internal" href="#policy-objects">策略对象</a></li>
|
||
<li><a class="reference internal" href="#process-watchers">进程监视器</a></li>
|
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<li><a class="reference internal" href="#custom-policies">自定义策略</a></li>
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