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| <h1>Source code for pyspark.accumulators</h1><div class="highlight"><pre> |
| <span></span><span class="c1">#</span> |
| <span class="c1"># Licensed to the Apache Software Foundation (ASF) under one or more</span> |
| <span class="c1"># contributor license agreements. See the NOTICE file distributed with</span> |
| <span class="c1"># this work for additional information regarding copyright ownership.</span> |
| <span class="c1"># The ASF licenses this file to You under the Apache License, Version 2.0</span> |
| <span class="c1"># (the "License"); you may not use this file except in compliance with</span> |
| <span class="c1"># the License. You may obtain a copy of the License at</span> |
| <span class="c1">#</span> |
| <span class="c1"># http://www.apache.org/licenses/LICENSE-2.0</span> |
| <span class="c1">#</span> |
| <span class="c1"># Unless required by applicable law or agreed to in writing, software</span> |
| <span class="c1"># distributed under the License is distributed on an "AS IS" BASIS,</span> |
| <span class="c1"># WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span> |
| <span class="c1"># See the License for the specific language governing permissions and</span> |
| <span class="c1"># limitations under the License.</span> |
| <span class="c1">#</span> |
| |
| <span class="kn">import</span> <span class="nn">sys</span> |
| <span class="kn">import</span> <span class="nn">select</span> |
| <span class="kn">import</span> <span class="nn">struct</span> |
| <span class="kn">import</span> <span class="nn">socketserver</span> <span class="k">as</span> <span class="nn">SocketServer</span> |
| <span class="kn">import</span> <span class="nn">threading</span> |
| <span class="kn">from</span> <span class="nn">typing</span> <span class="kn">import</span> <span class="n">Callable</span><span class="p">,</span> <span class="n">Dict</span><span class="p">,</span> <span class="n">Generic</span><span class="p">,</span> <span class="n">Tuple</span><span class="p">,</span> <span class="n">Type</span><span class="p">,</span> <span class="n">TYPE_CHECKING</span><span class="p">,</span> <span class="n">TypeVar</span><span class="p">,</span> <span class="n">Union</span> |
| |
| <span class="kn">from</span> <span class="nn">pyspark.serializers</span> <span class="kn">import</span> <span class="n">read_int</span><span class="p">,</span> <span class="n">CPickleSerializer</span> |
| <span class="kn">from</span> <span class="nn">pyspark.errors</span> <span class="kn">import</span> <span class="n">PySparkRuntimeError</span> |
| |
| <span class="k">if</span> <span class="n">TYPE_CHECKING</span><span class="p">:</span> |
| <span class="kn">from</span> <span class="nn">pyspark._typing</span> <span class="kn">import</span> <span class="n">SupportsIAdd</span> <span class="c1"># noqa: F401</span> |
| <span class="kn">import</span> <span class="nn">socketserver.BaseRequestHandler</span> <span class="c1"># type: ignore[import]</span> |
| |
| |
| <span class="n">__all__</span> <span class="o">=</span> <span class="p">[</span><span class="s2">"Accumulator"</span><span class="p">,</span> <span class="s2">"AccumulatorParam"</span><span class="p">]</span> |
| |
| <span class="n">T</span> <span class="o">=</span> <span class="n">TypeVar</span><span class="p">(</span><span class="s2">"T"</span><span class="p">)</span> |
| <span class="n">U</span> <span class="o">=</span> <span class="n">TypeVar</span><span class="p">(</span><span class="s2">"U"</span><span class="p">,</span> <span class="n">bound</span><span class="o">=</span><span class="s2">"SupportsIAdd"</span><span class="p">)</span> |
| |
| <span class="n">pickleSer</span> <span class="o">=</span> <span class="n">CPickleSerializer</span><span class="p">()</span> |
| |
| <span class="c1"># Holds accumulators registered on the current machine, keyed by ID. This is then used to send</span> |
| <span class="c1"># the local accumulator updates back to the driver program at the end of a task.</span> |
| <span class="n">_accumulatorRegistry</span><span class="p">:</span> <span class="n">Dict</span><span class="p">[</span><span class="nb">int</span><span class="p">,</span> <span class="s2">"Accumulator"</span><span class="p">]</span> <span class="o">=</span> <span class="p">{}</span> |
| |
| |
| <span class="k">def</span> <span class="nf">_deserialize_accumulator</span><span class="p">(</span> |
| <span class="n">aid</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">zero_value</span><span class="p">:</span> <span class="n">T</span><span class="p">,</span> <span class="n">accum_param</span><span class="p">:</span> <span class="s2">"AccumulatorParam[T]"</span> |
| <span class="p">)</span> <span class="o">-></span> <span class="s2">"Accumulator[T]"</span><span class="p">:</span> |
| <span class="kn">from</span> <span class="nn">pyspark.accumulators</span> <span class="kn">import</span> <span class="n">_accumulatorRegistry</span> |
| |
| <span class="c1"># If this certain accumulator was deserialized, don't overwrite it.</span> |
| <span class="k">if</span> <span class="n">aid</span> <span class="ow">in</span> <span class="n">_accumulatorRegistry</span><span class="p">:</span> |
| <span class="k">return</span> <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> |
| <span class="k">else</span><span class="p">:</span> |
| <span class="n">accum</span> <span class="o">=</span> <span class="n">Accumulator</span><span class="p">(</span><span class="n">aid</span><span class="p">,</span> <span class="n">zero_value</span><span class="p">,</span> <span class="n">accum_param</span><span class="p">)</span> |
| <span class="n">accum</span><span class="o">.</span><span class="n">_deserialized</span> <span class="o">=</span> <span class="kc">True</span> |
| <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> <span class="o">=</span> <span class="n">accum</span> |
| <span class="k">return</span> <span class="n">accum</span> |
| |
| |
| <div class="viewcode-block" id="Accumulator"><a class="viewcode-back" href="../../reference/api/pyspark.Accumulator.html#pyspark.Accumulator">[docs]</a><span class="k">class</span> <span class="nc">Accumulator</span><span class="p">(</span><span class="n">Generic</span><span class="p">[</span><span class="n">T</span><span class="p">]):</span> |
| |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> A shared variable that can be accumulated, i.e., has a commutative and associative "add"</span> |
| <span class="sd"> operation. Worker tasks on a Spark cluster can add values to an Accumulator with the `+=`</span> |
| <span class="sd"> operator, but only the driver program is allowed to access its value, using `value`.</span> |
| <span class="sd"> Updates from the workers get propagated automatically to the driver program.</span> |
| |
| <span class="sd"> While :class:`SparkContext` supports accumulators for primitive data types like :class:`int` and</span> |
| <span class="sd"> :class:`float`, users can also define accumulators for custom types by providing a custom</span> |
| <span class="sd"> :py:class:`AccumulatorParam` object. Refer to its doctest for an example.</span> |
| |
| <span class="sd"> Examples</span> |
| <span class="sd"> --------</span> |
| <span class="sd"> >>> a = sc.accumulator(1)</span> |
| <span class="sd"> >>> a.value</span> |
| <span class="sd"> 1</span> |
| <span class="sd"> >>> a.value = 2</span> |
| <span class="sd"> >>> a.value</span> |
| <span class="sd"> 2</span> |
| <span class="sd"> >>> a += 5</span> |
| <span class="sd"> >>> a.value</span> |
| <span class="sd"> 7</span> |
| <span class="sd"> >>> sc.accumulator(1.0).value</span> |
| <span class="sd"> 1.0</span> |
| <span class="sd"> >>> sc.accumulator(1j).value</span> |
| <span class="sd"> 1j</span> |
| <span class="sd"> >>> rdd = sc.parallelize([1,2,3])</span> |
| <span class="sd"> >>> def f(x):</span> |
| <span class="sd"> ... global a</span> |
| <span class="sd"> ... a += x</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> >>> rdd.foreach(f)</span> |
| <span class="sd"> >>> a.value</span> |
| <span class="sd"> 13</span> |
| <span class="sd"> >>> b = sc.accumulator(0)</span> |
| <span class="sd"> >>> def g(x):</span> |
| <span class="sd"> ... b.add(x)</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> >>> rdd.foreach(g)</span> |
| <span class="sd"> >>> b.value</span> |
| <span class="sd"> 6</span> |
| |
| <span class="sd"> >>> rdd.map(lambda x: a.value).collect() # doctest: +IGNORE_EXCEPTION_DETAIL</span> |
| <span class="sd"> Traceback (most recent call last):</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> Py4JJavaError: ...</span> |
| |
| <span class="sd"> >>> def h(x):</span> |
| <span class="sd"> ... global a</span> |
| <span class="sd"> ... a.value = 7</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> >>> rdd.foreach(h) # doctest: +IGNORE_EXCEPTION_DETAIL</span> |
| <span class="sd"> Traceback (most recent call last):</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> Py4JJavaError: ...</span> |
| |
| <span class="sd"> >>> sc.accumulator([1.0, 2.0, 3.0]) # doctest: +IGNORE_EXCEPTION_DETAIL</span> |
| <span class="sd"> Traceback (most recent call last):</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> TypeError: ...</span> |
| <span class="sd"> """</span> |
| |
| <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">aid</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">value</span><span class="p">:</span> <span class="n">T</span><span class="p">,</span> <span class="n">accum_param</span><span class="p">:</span> <span class="s2">"AccumulatorParam[T]"</span><span class="p">):</span> |
| <span class="w"> </span><span class="sd">"""Create a new Accumulator with a given initial value and AccumulatorParam object"""</span> |
| <span class="kn">from</span> <span class="nn">pyspark.accumulators</span> <span class="kn">import</span> <span class="n">_accumulatorRegistry</span> |
| |
| <span class="bp">self</span><span class="o">.</span><span class="n">aid</span> <span class="o">=</span> <span class="n">aid</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">accum_param</span> <span class="o">=</span> <span class="n">accum_param</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> <span class="o">=</span> <span class="n">value</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">_deserialized</span> <span class="o">=</span> <span class="kc">False</span> |
| <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span> |
| |
| <span class="k">def</span> <span class="nf">__reduce__</span><span class="p">(</span> |
| <span class="bp">self</span><span class="p">,</span> |
| <span class="p">)</span> <span class="o">-></span> <span class="n">Tuple</span><span class="p">[</span> |
| <span class="n">Callable</span><span class="p">[[</span><span class="nb">int</span><span class="p">,</span> <span class="n">T</span><span class="p">,</span> <span class="s2">"AccumulatorParam[T]"</span><span class="p">],</span> <span class="s2">"Accumulator[T]"</span><span class="p">],</span> |
| <span class="n">Tuple</span><span class="p">[</span><span class="nb">int</span><span class="p">,</span> <span class="n">T</span><span class="p">,</span> <span class="s2">"AccumulatorParam[T]"</span><span class="p">],</span> |
| <span class="p">]:</span> |
| <span class="w"> </span><span class="sd">"""Custom serialization; saves the zero value from our AccumulatorParam"""</span> |
| <span class="n">param</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">accum_param</span> |
| <span class="k">return</span> <span class="p">(</span><span class="n">_deserialize_accumulator</span><span class="p">,</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">aid</span><span class="p">,</span> <span class="n">param</span><span class="o">.</span><span class="n">zero</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">),</span> <span class="n">param</span><span class="p">))</span> |
| |
| <span class="nd">@property</span> |
| <span class="k">def</span> <span class="nf">value</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-></span> <span class="n">T</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""Get the accumulator's value; only usable in driver program"""</span> |
| <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deserialized</span><span class="p">:</span> |
| <span class="k">raise</span> <span class="n">PySparkRuntimeError</span><span class="p">(</span> |
| <span class="n">error_class</span><span class="o">=</span><span class="s2">"VALUE_NOT_ACCESSIBLE"</span><span class="p">,</span> |
| <span class="n">message_parameters</span><span class="o">=</span><span class="p">{</span> |
| <span class="s2">"value"</span><span class="p">:</span> <span class="s2">"Accumulator.value"</span><span class="p">,</span> |
| <span class="p">},</span> |
| <span class="p">)</span> |
| <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> |
| |
| <span class="nd">@value</span><span class="o">.</span><span class="n">setter</span> |
| <span class="k">def</span> <span class="nf">value</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">:</span> <span class="n">T</span><span class="p">)</span> <span class="o">-></span> <span class="kc">None</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""Sets the accumulator's value; only usable in driver program"""</span> |
| <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_deserialized</span><span class="p">:</span> |
| <span class="k">raise</span> <span class="n">PySparkRuntimeError</span><span class="p">(</span> |
| <span class="n">error_class</span><span class="o">=</span><span class="s2">"VALUE_NOT_ACCESSIBLE"</span><span class="p">,</span> |
| <span class="n">message_parameters</span><span class="o">=</span><span class="p">{</span> |
| <span class="s2">"value"</span><span class="p">:</span> <span class="s2">"Accumulator.value"</span><span class="p">,</span> |
| <span class="p">},</span> |
| <span class="p">)</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> <span class="o">=</span> <span class="n">value</span> |
| |
| <div class="viewcode-block" id="Accumulator.add"><a class="viewcode-back" href="../../reference/api/pyspark.Accumulator.add.html#pyspark.Accumulator.add">[docs]</a> <span class="k">def</span> <span class="nf">add</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">term</span><span class="p">:</span> <span class="n">T</span><span class="p">)</span> <span class="o">-></span> <span class="kc">None</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""Adds a term to this accumulator's value"""</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">_value</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">accum_param</span><span class="o">.</span><span class="n">addInPlace</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">,</span> <span class="n">term</span><span class="p">)</span></div> |
| |
| <span class="k">def</span> <span class="fm">__iadd__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">term</span><span class="p">:</span> <span class="n">T</span><span class="p">)</span> <span class="o">-></span> <span class="s2">"Accumulator[T]"</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""The += operator; adds a term to this accumulator's value"""</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">term</span><span class="p">)</span> |
| <span class="k">return</span> <span class="bp">self</span> |
| |
| <span class="k">def</span> <span class="fm">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-></span> <span class="nb">str</span><span class="p">:</span> |
| <span class="k">return</span> <span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">)</span> |
| |
| <span class="k">def</span> <span class="fm">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-></span> <span class="nb">str</span><span class="p">:</span> |
| <span class="k">return</span> <span class="s2">"Accumulator<id=</span><span class="si">%i</span><span class="s2">, value=</span><span class="si">%s</span><span class="s2">>"</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">aid</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_value</span><span class="p">)</span></div> |
| |
| |
| <div class="viewcode-block" id="AccumulatorParam"><a class="viewcode-back" href="../../reference/api/pyspark.AccumulatorParam.html#pyspark.AccumulatorParam">[docs]</a><span class="k">class</span> <span class="nc">AccumulatorParam</span><span class="p">(</span><span class="n">Generic</span><span class="p">[</span><span class="n">T</span><span class="p">]):</span> |
| |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> Helper object that defines how to accumulate values of a given type.</span> |
| |
| <span class="sd"> Examples</span> |
| <span class="sd"> --------</span> |
| <span class="sd"> >>> from pyspark.accumulators import AccumulatorParam</span> |
| <span class="sd"> >>> class VectorAccumulatorParam(AccumulatorParam):</span> |
| <span class="sd"> ... def zero(self, value):</span> |
| <span class="sd"> ... return [0.0] * len(value)</span> |
| <span class="sd"> ... def addInPlace(self, val1, val2):</span> |
| <span class="sd"> ... for i in range(len(val1)):</span> |
| <span class="sd"> ... val1[i] += val2[i]</span> |
| <span class="sd"> ... return val1</span> |
| <span class="sd"> >>> va = sc.accumulator([1.0, 2.0, 3.0], VectorAccumulatorParam())</span> |
| <span class="sd"> >>> va.value</span> |
| <span class="sd"> [1.0, 2.0, 3.0]</span> |
| <span class="sd"> >>> def g(x):</span> |
| <span class="sd"> ... global va</span> |
| <span class="sd"> ... va += [x] * 3</span> |
| <span class="sd"> ...</span> |
| <span class="sd"> >>> rdd = sc.parallelize([1,2,3])</span> |
| <span class="sd"> >>> rdd.foreach(g)</span> |
| <span class="sd"> >>> va.value</span> |
| <span class="sd"> [7.0, 8.0, 9.0]</span> |
| <span class="sd"> """</span> |
| |
| <div class="viewcode-block" id="AccumulatorParam.zero"><a class="viewcode-back" href="../../reference/api/pyspark.AccumulatorParam.zero.html#pyspark.AccumulatorParam.zero">[docs]</a> <span class="k">def</span> <span class="nf">zero</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">:</span> <span class="n">T</span><span class="p">)</span> <span class="o">-></span> <span class="n">T</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> Provide a "zero value" for the type, compatible in dimensions with the</span> |
| <span class="sd"> provided `value` (e.g., a zero vector)</span> |
| <span class="sd"> """</span> |
| <span class="k">raise</span> <span class="ne">NotImplementedError</span></div> |
| |
| <div class="viewcode-block" id="AccumulatorParam.addInPlace"><a class="viewcode-back" href="../../reference/api/pyspark.AccumulatorParam.addInPlace.html#pyspark.AccumulatorParam.addInPlace">[docs]</a> <span class="k">def</span> <span class="nf">addInPlace</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value1</span><span class="p">:</span> <span class="n">T</span><span class="p">,</span> <span class="n">value2</span><span class="p">:</span> <span class="n">T</span><span class="p">)</span> <span class="o">-></span> <span class="n">T</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> Add two values of the accumulator's data type, returning a new value;</span> |
| <span class="sd"> for efficiency, can also update `value1` in place and return it.</span> |
| <span class="sd"> """</span> |
| <span class="k">raise</span> <span class="ne">NotImplementedError</span></div></div> |
| |
| |
| <span class="k">class</span> <span class="nc">AddingAccumulatorParam</span><span class="p">(</span><span class="n">AccumulatorParam</span><span class="p">[</span><span class="n">U</span><span class="p">]):</span> |
| |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> An AccumulatorParam that uses the + operators to add values. Designed for simple types</span> |
| <span class="sd"> such as integers, floats, and lists. Requires the zero value for the underlying type</span> |
| <span class="sd"> as a parameter.</span> |
| <span class="sd"> """</span> |
| |
| <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">zero_value</span><span class="p">:</span> <span class="n">U</span><span class="p">):</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">zero_value</span> <span class="o">=</span> <span class="n">zero_value</span> |
| |
| <span class="k">def</span> <span class="nf">zero</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value</span><span class="p">:</span> <span class="n">U</span><span class="p">)</span> <span class="o">-></span> <span class="n">U</span><span class="p">:</span> |
| <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">zero_value</span> |
| |
| <span class="k">def</span> <span class="nf">addInPlace</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">value1</span><span class="p">:</span> <span class="n">U</span><span class="p">,</span> <span class="n">value2</span><span class="p">:</span> <span class="n">U</span><span class="p">)</span> <span class="o">-></span> <span class="n">U</span><span class="p">:</span> |
| <span class="n">value1</span> <span class="o">+=</span> <span class="n">value2</span> <span class="c1"># type: ignore[operator]</span> |
| <span class="k">return</span> <span class="n">value1</span> |
| |
| |
| <span class="c1"># Singleton accumulator params for some standard types</span> |
| <span class="n">INT_ACCUMULATOR_PARAM</span> <span class="o">=</span> <span class="n">AddingAccumulatorParam</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span> <span class="c1"># type: ignore[type-var]</span> |
| <span class="n">FLOAT_ACCUMULATOR_PARAM</span> <span class="o">=</span> <span class="n">AddingAccumulatorParam</span><span class="p">(</span><span class="mf">0.0</span><span class="p">)</span> <span class="c1"># type: ignore[type-var]</span> |
| <span class="n">COMPLEX_ACCUMULATOR_PARAM</span> <span class="o">=</span> <span class="n">AddingAccumulatorParam</span><span class="p">(</span><span class="mf">0.0</span><span class="n">j</span><span class="p">)</span> <span class="c1"># type: ignore[type-var]</span> |
| |
| |
| <span class="k">class</span> <span class="nc">_UpdateRequestHandler</span><span class="p">(</span><span class="n">SocketServer</span><span class="o">.</span><span class="n">StreamRequestHandler</span><span class="p">):</span> |
| |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> This handler will keep polling updates from the same socket until the</span> |
| <span class="sd"> server is shutdown.</span> |
| <span class="sd"> """</span> |
| |
| <span class="k">def</span> <span class="nf">handle</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-></span> <span class="kc">None</span><span class="p">:</span> |
| <span class="kn">from</span> <span class="nn">pyspark.accumulators</span> <span class="kn">import</span> <span class="n">_accumulatorRegistry</span> |
| |
| <span class="n">auth_token</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">server</span><span class="o">.</span><span class="n">auth_token</span> <span class="c1"># type: ignore[attr-defined]</span> |
| |
| <span class="k">def</span> <span class="nf">poll</span><span class="p">(</span><span class="n">func</span><span class="p">:</span> <span class="n">Callable</span><span class="p">[[],</span> <span class="nb">bool</span><span class="p">])</span> <span class="o">-></span> <span class="kc">None</span><span class="p">:</span> |
| <span class="k">while</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">server</span><span class="o">.</span><span class="n">server_shutdown</span><span class="p">:</span> <span class="c1"># type: ignore[attr-defined]</span> |
| <span class="c1"># Poll every 1 second for new data -- don't block in case of shutdown.</span> |
| <span class="n">r</span><span class="p">,</span> <span class="n">_</span><span class="p">,</span> <span class="n">_</span> <span class="o">=</span> <span class="n">select</span><span class="o">.</span><span class="n">select</span><span class="p">([</span><span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="p">],</span> <span class="p">[],</span> <span class="p">[],</span> <span class="mi">1</span><span class="p">)</span> |
| <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">rfile</span> <span class="ow">in</span> <span class="n">r</span> <span class="ow">and</span> <span class="n">func</span><span class="p">():</span> |
| <span class="k">break</span> |
| |
| <span class="k">def</span> <span class="nf">accum_updates</span><span class="p">()</span> <span class="o">-></span> <span class="nb">bool</span><span class="p">:</span> |
| <span class="n">num_updates</span> <span class="o">=</span> <span class="n">read_int</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="p">)</span> |
| <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">num_updates</span><span class="p">):</span> |
| <span class="p">(</span><span class="n">aid</span><span class="p">,</span> <span class="n">update</span><span class="p">)</span> <span class="o">=</span> <span class="n">pickleSer</span><span class="o">.</span><span class="n">_read_with_length</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="p">)</span> |
| <span class="n">_accumulatorRegistry</span><span class="p">[</span><span class="n">aid</span><span class="p">]</span> <span class="o">+=</span> <span class="n">update</span> |
| <span class="c1"># Write a byte in acknowledgement</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">wfile</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="n">struct</span><span class="o">.</span><span class="n">pack</span><span class="p">(</span><span class="s2">"!b"</span><span class="p">,</span> <span class="mi">1</span><span class="p">))</span> |
| <span class="k">return</span> <span class="kc">False</span> |
| |
| <span class="k">def</span> <span class="nf">authenticate_and_accum_updates</span><span class="p">()</span> <span class="o">-></span> <span class="nb">bool</span><span class="p">:</span> |
| <span class="n">received_token</span><span class="p">:</span> <span class="n">Union</span><span class="p">[</span><span class="nb">bytes</span><span class="p">,</span> <span class="nb">str</span><span class="p">]</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">rfile</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">auth_token</span><span class="p">))</span> |
| <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">received_token</span><span class="p">,</span> <span class="nb">bytes</span><span class="p">):</span> |
| <span class="n">received_token</span> <span class="o">=</span> <span class="n">received_token</span><span class="o">.</span><span class="n">decode</span><span class="p">(</span><span class="s2">"utf-8"</span><span class="p">)</span> |
| <span class="k">if</span> <span class="n">received_token</span> <span class="o">==</span> <span class="n">auth_token</span><span class="p">:</span> |
| <span class="n">accum_updates</span><span class="p">()</span> |
| <span class="c1"># we've authenticated, we can break out of the first loop now</span> |
| <span class="k">return</span> <span class="kc">True</span> |
| <span class="k">else</span><span class="p">:</span> |
| <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span> |
| <span class="s2">"The value of the provided token to the AccumulatorServer is not correct."</span> |
| <span class="p">)</span> |
| |
| <span class="c1"># first we keep polling till we've received the authentication token</span> |
| <span class="n">poll</span><span class="p">(</span><span class="n">authenticate_and_accum_updates</span><span class="p">)</span> |
| <span class="c1"># now we've authenticated, don't need to check for the token anymore</span> |
| <span class="n">poll</span><span class="p">(</span><span class="n">accum_updates</span><span class="p">)</span> |
| |
| |
| <span class="k">class</span> <span class="nc">AccumulatorServer</span><span class="p">(</span><span class="n">SocketServer</span><span class="o">.</span><span class="n">TCPServer</span><span class="p">):</span> |
| <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span> |
| <span class="bp">self</span><span class="p">,</span> |
| <span class="n">server_address</span><span class="p">:</span> <span class="n">Tuple</span><span class="p">[</span><span class="nb">str</span><span class="p">,</span> <span class="nb">int</span><span class="p">],</span> |
| <span class="n">RequestHandlerClass</span><span class="p">:</span> <span class="n">Type</span><span class="p">[</span><span class="s2">"socketserver.BaseRequestHandler"</span><span class="p">],</span> |
| <span class="n">auth_token</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span> |
| <span class="p">):</span> |
| <span class="n">SocketServer</span><span class="o">.</span><span class="n">TCPServer</span><span class="o">.</span><span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">server_address</span><span class="p">,</span> <span class="n">RequestHandlerClass</span><span class="p">)</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">auth_token</span> <span class="o">=</span> <span class="n">auth_token</span> |
| |
| <span class="w"> </span><span class="sd">"""</span> |
| <span class="sd"> A simple TCP server that intercepts shutdown() in order to interrupt</span> |
| <span class="sd"> our continuous polling on the handler.</span> |
| <span class="sd"> """</span> |
| <span class="n">server_shutdown</span> <span class="o">=</span> <span class="kc">False</span> |
| |
| <span class="k">def</span> <span class="nf">shutdown</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-></span> <span class="kc">None</span><span class="p">:</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">server_shutdown</span> <span class="o">=</span> <span class="kc">True</span> |
| <span class="n">SocketServer</span><span class="o">.</span><span class="n">TCPServer</span><span class="o">.</span><span class="n">shutdown</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> |
| <span class="bp">self</span><span class="o">.</span><span class="n">server_close</span><span class="p">()</span> |
| |
| |
| <span class="k">def</span> <span class="nf">_start_update_server</span><span class="p">(</span><span class="n">auth_token</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-></span> <span class="n">AccumulatorServer</span><span class="p">:</span> |
| <span class="w"> </span><span class="sd">"""Start a TCP server to receive accumulator updates in a daemon thread, and returns it"""</span> |
| <span class="n">server</span> <span class="o">=</span> <span class="n">AccumulatorServer</span><span class="p">((</span><span class="s2">"localhost"</span><span class="p">,</span> <span class="mi">0</span><span class="p">),</span> <span class="n">_UpdateRequestHandler</span><span class="p">,</span> <span class="n">auth_token</span><span class="p">)</span> |
| <span class="n">thread</span> <span class="o">=</span> <span class="n">threading</span><span class="o">.</span><span class="n">Thread</span><span class="p">(</span><span class="n">target</span><span class="o">=</span><span class="n">server</span><span class="o">.</span><span class="n">serve_forever</span><span class="p">)</span> |
| <span class="n">thread</span><span class="o">.</span><span class="n">daemon</span> <span class="o">=</span> <span class="kc">True</span> |
| <span class="n">thread</span><span class="o">.</span><span class="n">start</span><span class="p">()</span> |
| <span class="k">return</span> <span class="n">server</span> |
| |
| |
| <span class="k">if</span> <span class="vm">__name__</span> <span class="o">==</span> <span class="s2">"__main__"</span><span class="p">:</span> |
| <span class="kn">import</span> <span class="nn">doctest</span> |
| |
| <span class="kn">from</span> <span class="nn">pyspark.context</span> <span class="kn">import</span> <span class="n">SparkContext</span> |
| |
| <span class="n">globs</span> <span class="o">=</span> <span class="nb">globals</span><span class="p">()</span><span class="o">.</span><span class="n">copy</span><span class="p">()</span> |
| <span class="c1"># The small batch size here ensures that we see multiple batches,</span> |
| <span class="c1"># even in these small test examples:</span> |
| <span class="n">globs</span><span class="p">[</span><span class="s2">"sc"</span><span class="p">]</span> <span class="o">=</span> <span class="n">SparkContext</span><span class="p">(</span><span class="s2">"local"</span><span class="p">,</span> <span class="s2">"test"</span><span class="p">)</span> |
| <span class="p">(</span><span class="n">failure_count</span><span class="p">,</span> <span class="n">test_count</span><span class="p">)</span> <span class="o">=</span> <span class="n">doctest</span><span class="o">.</span><span class="n">testmod</span><span class="p">(</span><span class="n">globs</span><span class="o">=</span><span class="n">globs</span><span class="p">,</span> <span class="n">optionflags</span><span class="o">=</span><span class="n">doctest</span><span class="o">.</span><span class="n">ELLIPSIS</span><span class="p">)</span> |
| <span class="n">globs</span><span class="p">[</span><span class="s2">"sc"</span><span class="p">]</span><span class="o">.</span><span class="n">stop</span><span class="p">()</span> |
| <span class="k">if</span> <span class="n">failure_count</span><span class="p">:</span> |
| <span class="n">sys</span><span class="o">.</span><span class="n">exit</span><span class="p">(</span><span class="o">-</span><span class="mi">1</span><span class="p">)</span> |
| </pre></div> |
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