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  <h1>Source code for pyspark.serializers</h1><div class="highlight"><pre>
<span class="c">#</span>
<span class="c"># Licensed to the Apache Software Foundation (ASF) under one or more</span>
<span class="c"># contributor license agreements.  See the NOTICE file distributed with</span>
<span class="c"># this work for additional information regarding copyright ownership.</span>
<span class="c"># The ASF licenses this file to You under the Apache License, Version 2.0</span>
<span class="c"># (the &quot;License&quot;); you may not use this file except in compliance with</span>
<span class="c"># the License.  You may obtain a copy of the License at</span>
<span class="c">#</span>
<span class="c">#    http://www.apache.org/licenses/LICENSE-2.0</span>
<span class="c">#</span>
<span class="c"># Unless required by applicable law or agreed to in writing, software</span>
<span class="c"># distributed under the License is distributed on an &quot;AS IS&quot; BASIS,</span>
<span class="c"># WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span>
<span class="c"># See the License for the specific language governing permissions and</span>
<span class="c"># limitations under the License.</span>
<span class="c">#</span>

<span class="sd">&quot;&quot;&quot;</span>
<span class="sd">PySpark supports custom serializers for transferring data; this can improve</span>
<span class="sd">performance.</span>

<span class="sd">By default, PySpark uses L{PickleSerializer} to serialize objects using Python&#39;s</span>
<span class="sd">C{cPickle} serializer, which can serialize nearly any Python object.</span>
<span class="sd">Other serializers, like L{MarshalSerializer}, support fewer datatypes but can be</span>
<span class="sd">faster.</span>

<span class="sd">The serializer is chosen when creating L{SparkContext}:</span>

<span class="sd">&gt;&gt;&gt; from pyspark.context import SparkContext</span>
<span class="sd">&gt;&gt;&gt; from pyspark.serializers import MarshalSerializer</span>
<span class="sd">&gt;&gt;&gt; sc = SparkContext(&#39;local&#39;, &#39;test&#39;, serializer=MarshalSerializer())</span>
<span class="sd">&gt;&gt;&gt; sc.parallelize(list(range(1000))).map(lambda x: 2 * x).take(10)</span>
<span class="sd">[0, 2, 4, 6, 8, 10, 12, 14, 16, 18]</span>
<span class="sd">&gt;&gt;&gt; sc.stop()</span>

<span class="sd">PySpark serialize objects in batches; By default, the batch size is chosen based</span>
<span class="sd">on the size of objects, also configurable by SparkContext&#39;s C{batchSize} parameter:</span>

<span class="sd">&gt;&gt;&gt; sc = SparkContext(&#39;local&#39;, &#39;test&#39;, batchSize=2)</span>
<span class="sd">&gt;&gt;&gt; rdd = sc.parallelize(range(16), 4).map(lambda x: x)</span>

<span class="sd">Behind the scenes, this creates a JavaRDD with four partitions, each of</span>
<span class="sd">which contains two batches of two objects:</span>

<span class="sd">&gt;&gt;&gt; rdd.glom().collect()</span>
<span class="sd">[[0, 1, 2, 3], [4, 5, 6, 7], [8, 9, 10, 11], [12, 13, 14, 15]]</span>
<span class="sd">&gt;&gt;&gt; int(rdd._jrdd.count())</span>
<span class="sd">8</span>
<span class="sd">&gt;&gt;&gt; sc.stop()</span>
<span class="sd">&quot;&quot;&quot;</span>

<span class="kn">import</span> <span class="nn">sys</span>
<span class="kn">from</span> <span class="nn">itertools</span> <span class="kn">import</span> <span class="n">chain</span><span class="p">,</span> <span class="n">product</span>
<span class="kn">import</span> <span class="nn">marshal</span>
<span class="kn">import</span> <span class="nn">struct</span>
<span class="kn">import</span> <span class="nn">types</span>
<span class="kn">import</span> <span class="nn">collections</span>
<span class="kn">import</span> <span class="nn">zlib</span>
<span class="kn">import</span> <span class="nn">itertools</span>

<span class="k">if</span> <span class="n">sys</span><span class="o">.</span><span class="n">version</span> <span class="o">&lt;</span> <span class="s">&#39;3&#39;</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">cPickle</span> <span class="kn">as</span> <span class="nn">pickle</span>
    <span class="n">protocol</span> <span class="o">=</span> <span class="mi">2</span>
    <span class="kn">from</span> <span class="nn">itertools</span> <span class="kn">import</span> <span class="n">izip</span> <span class="k">as</span> <span class="nb">zip</span>
<span class="k">else</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">pickle</span>
    <span class="n">protocol</span> <span class="o">=</span> <span class="mi">3</span>
    <span class="nb">xrange</span> <span class="o">=</span> <span class="nb">range</span>

<span class="kn">from</span> <span class="nn">pyspark</span> <span class="kn">import</span> <span class="n">cloudpickle</span>


<span class="n">__all__</span> <span class="o">=</span> <span class="p">[</span><span class="s">&quot;PickleSerializer&quot;</span><span class="p">,</span> <span class="s">&quot;MarshalSerializer&quot;</span><span class="p">,</span> <span class="s">&quot;UTF8Deserializer&quot;</span><span class="p">]</span>


<span class="k">class</span> <span class="nc">SpecialLengths</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
    <span class="n">END_OF_DATA_SECTION</span> <span class="o">=</span> <span class="o">-</span><span class="mi">1</span>
    <span class="n">PYTHON_EXCEPTION_THROWN</span> <span class="o">=</span> <span class="o">-</span><span class="mi">2</span>
    <span class="n">TIMING_DATA</span> <span class="o">=</span> <span class="o">-</span><span class="mi">3</span>
    <span class="n">END_OF_STREAM</span> <span class="o">=</span> <span class="o">-</span><span class="mi">4</span>
    <span class="n">NULL</span> <span class="o">=</span> <span class="o">-</span><span class="mi">5</span>


<span class="k">class</span> <span class="nc">Serializer</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>

    <span class="k">def</span> <span class="nf">dump_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">iterator</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Serialize an iterator of objects to the output stream.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">raise</span> <span class="ne">NotImplementedError</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Return an iterator of deserialized objects from the input stream.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">raise</span> <span class="ne">NotImplementedError</span>

    <span class="k">def</span> <span class="nf">_load_stream_without_unbatching</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">load_stream</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>

    <span class="c"># Note: our notion of &quot;equality&quot; is that output generated by</span>
    <span class="c"># equal serializers can be deserialized using the same serializer.</span>

    <span class="c"># This default implementation handles the simple cases;</span>
    <span class="c"># subclasses should override __eq__ as appropriate.</span>

    <span class="k">def</span> <span class="nf">__eq__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span>
        <span class="k">return</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">)</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span> <span class="o">==</span> <span class="n">other</span><span class="o">.</span><span class="n">__dict__</span>

    <span class="k">def</span> <span class="nf">__ne__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span>
        <span class="k">return</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">__eq__</span><span class="p">(</span><span class="n">other</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;</span><span class="si">%s</span><span class="s">()&quot;</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span>

    <span class="k">def</span> <span class="nf">__hash__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="nb">hash</span><span class="p">(</span><span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="p">))</span>


<span class="k">class</span> <span class="nc">FramedSerializer</span><span class="p">(</span><span class="n">Serializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Serializer that writes objects as a stream of (length, data) pairs,</span>
<span class="sd">    where C{length} is a 32-bit integer and data is C{length} bytes.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="c"># On Python 2.6, we can&#39;t write bytearrays to streams, so we need to convert them</span>
        <span class="c"># to strings first. Check if the version number is that old.</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_only_write_strings</span> <span class="o">=</span> <span class="n">sys</span><span class="o">.</span><span class="n">version_info</span><span class="p">[</span><span class="mi">0</span><span class="p">:</span><span class="mi">2</span><span class="p">]</span> <span class="o">&lt;=</span> <span class="p">(</span><span class="mi">2</span><span class="p">,</span> <span class="mi">6</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">dump_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">iterator</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">iterator</span><span class="p">:</span>
            <span class="bp">self</span><span class="o">.</span><span class="n">_write_with_length</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">stream</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">while</span> <span class="bp">True</span><span class="p">:</span>
            <span class="k">try</span><span class="p">:</span>
                <span class="k">yield</span> <span class="bp">self</span><span class="o">.</span><span class="n">_read_with_length</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>
            <span class="k">except</span> <span class="ne">EOFError</span><span class="p">:</span>
                <span class="k">return</span>

    <span class="k">def</span> <span class="nf">_write_with_length</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="n">serialized</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>
        <span class="k">if</span> <span class="n">serialized</span> <span class="ow">is</span> <span class="bp">None</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">&quot;serialized value should not be None&quot;</span><span class="p">)</span>
        <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">serialized</span><span class="p">)</span> <span class="o">&gt;</span> <span class="p">(</span><span class="mi">1</span> <span class="o">&lt;&lt;</span> <span class="mi">31</span><span class="p">):</span>
            <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">&quot;can not serialize object larger than 2G&quot;</span><span class="p">)</span>
        <span class="n">write_int</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">serialized</span><span class="p">),</span> <span class="n">stream</span><span class="p">)</span>
        <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_only_write_strings</span><span class="p">:</span>
            <span class="n">stream</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="nb">str</span><span class="p">(</span><span class="n">serialized</span><span class="p">))</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">stream</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="n">serialized</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">_read_with_length</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="n">length</span> <span class="o">=</span> <span class="n">read_int</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>
        <span class="k">if</span> <span class="n">length</span> <span class="o">==</span> <span class="n">SpecialLengths</span><span class="o">.</span><span class="n">END_OF_DATA_SECTION</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">EOFError</span>
        <span class="k">elif</span> <span class="n">length</span> <span class="o">==</span> <span class="n">SpecialLengths</span><span class="o">.</span><span class="n">NULL</span><span class="p">:</span>
            <span class="k">return</span> <span class="bp">None</span>
        <span class="n">obj</span> <span class="o">=</span> <span class="n">stream</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="n">length</span><span class="p">)</span>
        <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span> <span class="o">&lt;</span> <span class="n">length</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">EOFError</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Serialize an object into a byte array.</span>
<span class="sd">        When batching is used, this will be called with an array of objects.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">raise</span> <span class="ne">NotImplementedError</span>

    <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">        Deserialize an object from a byte array.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="k">raise</span> <span class="ne">NotImplementedError</span>


<span class="k">class</span> <span class="nc">BatchedSerializer</span><span class="p">(</span><span class="n">Serializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Serializes a stream of objects in batches by calling its wrapped</span>
<span class="sd">    Serializer with streams of objects.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="n">UNLIMITED_BATCH_SIZE</span> <span class="o">=</span> <span class="o">-</span><span class="mi">1</span>
    <span class="n">UNKNOWN_BATCH_SIZE</span> <span class="o">=</span> <span class="mi">0</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">serializer</span><span class="p">,</span> <span class="n">batchSize</span><span class="o">=</span><span class="n">UNLIMITED_BATCH_SIZE</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span> <span class="o">=</span> <span class="n">serializer</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span> <span class="o">=</span> <span class="n">batchSize</span>

    <span class="k">def</span> <span class="nf">_batched</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">iterator</span><span class="p">):</span>
        <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span> <span class="o">==</span> <span class="bp">self</span><span class="o">.</span><span class="n">UNLIMITED_BATCH_SIZE</span><span class="p">:</span>
            <span class="k">yield</span> <span class="nb">list</span><span class="p">(</span><span class="n">iterator</span><span class="p">)</span>
        <span class="k">elif</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">iterator</span><span class="p">,</span> <span class="s">&quot;__len__&quot;</span><span class="p">)</span> <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">iterator</span><span class="p">,</span> <span class="s">&quot;__getslice__&quot;</span><span class="p">):</span>
            <span class="n">n</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="n">iterator</span><span class="p">)</span>
            <span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">xrange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="n">n</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span><span class="p">):</span>
                <span class="k">yield</span> <span class="n">iterator</span><span class="p">[</span><span class="n">i</span><span class="p">:</span> <span class="n">i</span> <span class="o">+</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span><span class="p">]</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">items</span> <span class="o">=</span> <span class="p">[]</span>
            <span class="n">count</span> <span class="o">=</span> <span class="mi">0</span>
            <span class="k">for</span> <span class="n">item</span> <span class="ow">in</span> <span class="n">iterator</span><span class="p">:</span>
                <span class="n">items</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">item</span><span class="p">)</span>
                <span class="n">count</span> <span class="o">+=</span> <span class="mi">1</span>
                <span class="k">if</span> <span class="n">count</span> <span class="o">==</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span><span class="p">:</span>
                    <span class="k">yield</span> <span class="n">items</span>
                    <span class="n">items</span> <span class="o">=</span> <span class="p">[]</span>
                    <span class="n">count</span> <span class="o">=</span> <span class="mi">0</span>
            <span class="k">if</span> <span class="n">items</span><span class="p">:</span>
                <span class="k">yield</span> <span class="n">items</span>

    <span class="k">def</span> <span class="nf">dump_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">iterator</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="o">.</span><span class="n">dump_stream</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_batched</span><span class="p">(</span><span class="n">iterator</span><span class="p">),</span> <span class="n">stream</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">chain</span><span class="o">.</span><span class="n">from_iterable</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_load_stream_without_unbatching</span><span class="p">(</span><span class="n">stream</span><span class="p">))</span>

    <span class="k">def</span> <span class="nf">_load_stream_without_unbatching</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="o">.</span><span class="n">load_stream</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;BatchedSerializer(</span><span class="si">%s</span><span class="s">, </span><span class="si">%d</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="p">(</span><span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="p">),</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span><span class="p">)</span>


<span class="k">class</span> <span class="nc">FlattenedValuesSerializer</span><span class="p">(</span><span class="n">BatchedSerializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Serializes a stream of list of pairs, split the list of values</span>
<span class="sd">    which contain more than a certain number of objects to make them</span>
<span class="sd">    have similar sizes.</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">serializer</span><span class="p">,</span> <span class="n">batchSize</span><span class="o">=</span><span class="mi">10</span><span class="p">):</span>
        <span class="n">BatchedSerializer</span><span class="o">.</span><span class="n">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">serializer</span><span class="p">,</span> <span class="n">batchSize</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">_batched</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">iterator</span><span class="p">):</span>
        <span class="n">n</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span>
        <span class="k">for</span> <span class="n">key</span><span class="p">,</span> <span class="n">values</span> <span class="ow">in</span> <span class="n">iterator</span><span class="p">:</span>
            <span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="nb">len</span><span class="p">(</span><span class="n">values</span><span class="p">),</span> <span class="n">n</span><span class="p">):</span>
                <span class="k">yield</span> <span class="n">key</span><span class="p">,</span> <span class="n">values</span><span class="p">[</span><span class="n">i</span><span class="p">:</span><span class="n">i</span> <span class="o">+</span> <span class="n">n</span><span class="p">]</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="o">.</span><span class="n">load_stream</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;FlattenedValuesSerializer(</span><span class="si">%s</span><span class="s">, </span><span class="si">%d</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">batchSize</span><span class="p">)</span>


<span class="k">class</span> <span class="nc">AutoBatchedSerializer</span><span class="p">(</span><span class="n">BatchedSerializer</span><span class="p">):</span>
    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Choose the size of batch automatically based on the size of object</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">serializer</span><span class="p">,</span> <span class="n">bestSize</span><span class="o">=</span><span class="mi">1</span> <span class="o">&lt;&lt;</span> <span class="mi">16</span><span class="p">):</span>
        <span class="n">BatchedSerializer</span><span class="o">.</span><span class="n">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">serializer</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">UNKNOWN_BATCH_SIZE</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">bestSize</span> <span class="o">=</span> <span class="n">bestSize</span>

    <span class="k">def</span> <span class="nf">dump_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">iterator</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="n">batch</span><span class="p">,</span> <span class="n">best</span> <span class="o">=</span> <span class="mi">1</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">bestSize</span>
        <span class="n">iterator</span> <span class="o">=</span> <span class="nb">iter</span><span class="p">(</span><span class="n">iterator</span><span class="p">)</span>
        <span class="k">while</span> <span class="bp">True</span><span class="p">:</span>
            <span class="n">vs</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">itertools</span><span class="o">.</span><span class="n">islice</span><span class="p">(</span><span class="n">iterator</span><span class="p">,</span> <span class="n">batch</span><span class="p">))</span>
            <span class="k">if</span> <span class="ow">not</span> <span class="n">vs</span><span class="p">:</span>
                <span class="k">break</span>

            <span class="nb">bytes</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">vs</span><span class="p">)</span>
            <span class="n">write_int</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="nb">bytes</span><span class="p">),</span> <span class="n">stream</span><span class="p">)</span>
            <span class="n">stream</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="nb">bytes</span><span class="p">)</span>

            <span class="n">size</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="nb">bytes</span><span class="p">)</span>
            <span class="k">if</span> <span class="n">size</span> <span class="o">&lt;</span> <span class="n">best</span><span class="p">:</span>
                <span class="n">batch</span> <span class="o">*=</span> <span class="mi">2</span>
            <span class="k">elif</span> <span class="n">size</span> <span class="o">&gt;</span> <span class="n">best</span> <span class="o">*</span> <span class="mi">10</span> <span class="ow">and</span> <span class="n">batch</span> <span class="o">&gt;</span> <span class="mi">1</span><span class="p">:</span>
                <span class="n">batch</span> <span class="o">//=</span> <span class="mi">2</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;AutoBatchedSerializer(</span><span class="si">%s</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span>


<span class="k">class</span> <span class="nc">CartesianDeserializer</span><span class="p">(</span><span class="n">FramedSerializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Deserializes the JavaRDD cartesian() of two PythonRDDs.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">key_ser</span><span class="p">,</span> <span class="n">val_ser</span><span class="p">):</span>
        <span class="n">FramedSerializer</span><span class="o">.</span><span class="n">__init__</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">key_ser</span> <span class="o">=</span> <span class="n">key_ser</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">val_ser</span> <span class="o">=</span> <span class="n">val_ser</span>

    <span class="k">def</span> <span class="nf">prepare_keys_values</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="n">key_stream</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">key_ser</span><span class="o">.</span><span class="n">_load_stream_without_unbatching</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>
        <span class="n">val_stream</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">val_ser</span><span class="o">.</span><span class="n">_load_stream_without_unbatching</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>
        <span class="n">key_is_batched</span> <span class="o">=</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">key_ser</span><span class="p">,</span> <span class="n">BatchedSerializer</span><span class="p">)</span>
        <span class="n">val_is_batched</span> <span class="o">=</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">val_ser</span><span class="p">,</span> <span class="n">BatchedSerializer</span><span class="p">)</span>
        <span class="k">for</span> <span class="p">(</span><span class="n">keys</span><span class="p">,</span> <span class="n">vals</span><span class="p">)</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="n">key_stream</span><span class="p">,</span> <span class="n">val_stream</span><span class="p">):</span>
            <span class="n">keys</span> <span class="o">=</span> <span class="n">keys</span> <span class="k">if</span> <span class="n">key_is_batched</span> <span class="k">else</span> <span class="p">[</span><span class="n">keys</span><span class="p">]</span>
            <span class="n">vals</span> <span class="o">=</span> <span class="n">vals</span> <span class="k">if</span> <span class="n">val_is_batched</span> <span class="k">else</span> <span class="p">[</span><span class="n">vals</span><span class="p">]</span>
            <span class="k">yield</span> <span class="p">(</span><span class="n">keys</span><span class="p">,</span> <span class="n">vals</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">for</span> <span class="p">(</span><span class="n">keys</span><span class="p">,</span> <span class="n">vals</span><span class="p">)</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">prepare_keys_values</span><span class="p">(</span><span class="n">stream</span><span class="p">):</span>
            <span class="k">for</span> <span class="n">pair</span> <span class="ow">in</span> <span class="n">product</span><span class="p">(</span><span class="n">keys</span><span class="p">,</span> <span class="n">vals</span><span class="p">):</span>
                <span class="k">yield</span> <span class="n">pair</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;CartesianDeserializer(</span><span class="si">%s</span><span class="s">, </span><span class="si">%s</span><span class="s">)&quot;</span> <span class="o">%</span> \
               <span class="p">(</span><span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">key_ser</span><span class="p">),</span> <span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">val_ser</span><span class="p">))</span>


<span class="k">class</span> <span class="nc">PairDeserializer</span><span class="p">(</span><span class="n">CartesianDeserializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Deserializes the JavaRDD zip() of two PythonRDDs.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">for</span> <span class="p">(</span><span class="n">keys</span><span class="p">,</span> <span class="n">vals</span><span class="p">)</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">prepare_keys_values</span><span class="p">(</span><span class="n">stream</span><span class="p">):</span>
            <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">keys</span><span class="p">)</span> <span class="o">!=</span> <span class="nb">len</span><span class="p">(</span><span class="n">vals</span><span class="p">):</span>
                <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s">&quot;Can not deserialize RDD with different number of items&quot;</span>
                                 <span class="s">&quot; in pair: (</span><span class="si">%d</span><span class="s">, </span><span class="si">%d</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">keys</span><span class="p">),</span> <span class="nb">len</span><span class="p">(</span><span class="n">vals</span><span class="p">)))</span>
            <span class="k">for</span> <span class="n">pair</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="n">keys</span><span class="p">,</span> <span class="n">vals</span><span class="p">):</span>
                <span class="k">yield</span> <span class="n">pair</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;PairDeserializer(</span><span class="si">%s</span><span class="s">, </span><span class="si">%s</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="p">(</span><span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">key_ser</span><span class="p">),</span> <span class="nb">str</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">val_ser</span><span class="p">))</span>


<span class="k">class</span> <span class="nc">NoOpSerializer</span><span class="p">(</span><span class="n">FramedSerializer</span><span class="p">):</span>

    <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">obj</span>

    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">obj</span>


<span class="c"># Hook namedtuple, make it picklable</span>

<span class="n">__cls</span> <span class="o">=</span> <span class="p">{}</span>


<span class="k">def</span> <span class="nf">_restore</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span>
    <span class="sd">&quot;&quot;&quot; Restore an object of namedtuple&quot;&quot;&quot;</span>
    <span class="n">k</span> <span class="o">=</span> <span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">fields</span><span class="p">)</span>
    <span class="n">cls</span> <span class="o">=</span> <span class="n">__cls</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">k</span><span class="p">)</span>
    <span class="k">if</span> <span class="n">cls</span> <span class="ow">is</span> <span class="bp">None</span><span class="p">:</span>
        <span class="n">cls</span> <span class="o">=</span> <span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">fields</span><span class="p">)</span>
        <span class="n">__cls</span><span class="p">[</span><span class="n">k</span><span class="p">]</span> <span class="o">=</span> <span class="n">cls</span>
    <span class="k">return</span> <span class="n">cls</span><span class="p">(</span><span class="o">*</span><span class="n">value</span><span class="p">)</span>


<span class="k">def</span> <span class="nf">_hack_namedtuple</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span>
    <span class="sd">&quot;&quot;&quot; Make class generated by namedtuple picklable &quot;&quot;&quot;</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">__name__</span>
    <span class="n">fields</span> <span class="o">=</span> <span class="n">cls</span><span class="o">.</span><span class="n">_fields</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="k">return</span> <span class="p">(</span><span class="n">_restore</span><span class="p">,</span> <span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="nb">tuple</span><span class="p">(</span><span class="bp">self</span><span class="p">)))</span>
    <span class="n">cls</span><span class="o">.</span><span class="n">__reduce__</span> <span class="o">=</span> <span class="n">__reduce__</span>
    <span class="n">cls</span><span class="o">.</span><span class="n">_is_namedtuple_</span> <span class="o">=</span> <span class="bp">True</span>
    <span class="k">return</span> <span class="n">cls</span>


<span class="k">def</span> <span class="nf">_hijack_namedtuple</span><span class="p">():</span>
    <span class="sd">&quot;&quot;&quot; Hack namedtuple() to make it picklable &quot;&quot;&quot;</span>
    <span class="c"># hijack only one time</span>
    <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="p">,</span> <span class="s">&quot;__hijack&quot;</span><span class="p">):</span>
        <span class="k">return</span>

    <span class="k">global</span> <span class="n">_old_namedtuple</span>  <span class="c"># or it will put in closure</span>

    <span class="k">def</span> <span class="nf">_copy_func</span><span class="p">(</span><span class="n">f</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">types</span><span class="o">.</span><span class="n">FunctionType</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">__code__</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">__globals__</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span>
                                  <span class="n">f</span><span class="o">.</span><span class="n">__defaults__</span><span class="p">,</span> <span class="n">f</span><span class="o">.</span><span class="n">__closure__</span><span class="p">)</span>

    <span class="n">_old_namedtuple</span> <span class="o">=</span> <span class="n">_copy_func</span><span class="p">(</span><span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">namedtuple</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span>
        <span class="n">cls</span> <span class="o">=</span> <span class="n">_old_namedtuple</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span>
        <span class="k">return</span> <span class="n">_hack_namedtuple</span><span class="p">(</span><span class="n">cls</span><span class="p">)</span>

    <span class="c"># replace namedtuple with new one</span>
    <span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="o">.</span><span class="n">__globals__</span><span class="p">[</span><span class="s">&quot;_old_namedtuple&quot;</span><span class="p">]</span> <span class="o">=</span> <span class="n">_old_namedtuple</span>
    <span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="o">.</span><span class="n">__globals__</span><span class="p">[</span><span class="s">&quot;_hack_namedtuple&quot;</span><span class="p">]</span> <span class="o">=</span> <span class="n">_hack_namedtuple</span>
    <span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="o">.</span><span class="n">__code__</span> <span class="o">=</span> <span class="n">namedtuple</span><span class="o">.</span><span class="n">__code__</span>
    <span class="n">collections</span><span class="o">.</span><span class="n">namedtuple</span><span class="o">.</span><span class="n">__hijack</span> <span class="o">=</span> <span class="mi">1</span>

    <span class="c"># hack the cls already generated by namedtuple</span>
    <span class="c"># those created in other module can be pickled as normal,</span>
    <span class="c"># so only hack those in __main__ module</span>
    <span class="k">for</span> <span class="n">n</span><span class="p">,</span> <span class="n">o</span> <span class="ow">in</span> <span class="n">sys</span><span class="o">.</span><span class="n">modules</span><span class="p">[</span><span class="s">&quot;__main__&quot;</span><span class="p">]</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">items</span><span class="p">():</span>
        <span class="k">if</span> <span class="p">(</span><span class="nb">type</span><span class="p">(</span><span class="n">o</span><span class="p">)</span> <span class="ow">is</span> <span class="nb">type</span> <span class="ow">and</span> <span class="n">o</span><span class="o">.</span><span class="n">__base__</span> <span class="ow">is</span> <span class="nb">tuple</span>
                <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">o</span><span class="p">,</span> <span class="s">&quot;_fields&quot;</span><span class="p">)</span>
                <span class="ow">and</span> <span class="s">&quot;__reduce__&quot;</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">o</span><span class="o">.</span><span class="n">__dict__</span><span class="p">):</span>
            <span class="n">_hack_namedtuple</span><span class="p">(</span><span class="n">o</span><span class="p">)</span>  <span class="c"># hack inplace</span>


<span class="n">_hijack_namedtuple</span><span class="p">()</span>


<div class="viewcode-block" id="PickleSerializer"><a class="viewcode-back" href="../../pyspark.html#pyspark.PickleSerializer">[docs]</a><span class="k">class</span> <span class="nc">PickleSerializer</span><span class="p">(</span><span class="n">FramedSerializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Serializes objects using Python&#39;s pickle serializer:</span>

<span class="sd">        http://docs.python.org/2/library/pickle.html</span>

<span class="sd">    This serializer supports nearly any Python object, but may</span>
<span class="sd">    not be as fast as more specialized serializers.</span>
<span class="sd">    &quot;&quot;&quot;</span>

<div class="viewcode-block" id="PickleSerializer.dumps"><a class="viewcode-back" href="../../pyspark.html#pyspark.PickleSerializer.dumps">[docs]</a>    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">pickle</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">protocol</span><span class="p">)</span>
</div>
    <span class="k">if</span> <span class="n">sys</span><span class="o">.</span><span class="n">version</span> <span class="o">&gt;=</span> <span class="s">&#39;3&#39;</span><span class="p">:</span>
        <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">,</span> <span class="n">encoding</span><span class="o">=</span><span class="s">&quot;bytes&quot;</span><span class="p">):</span>
            <span class="k">return</span> <span class="n">pickle</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">encoding</span><span class="o">=</span><span class="n">encoding</span><span class="p">)</span>
    <span class="k">else</span><span class="p">:</span>
<div class="viewcode-block" id="PickleSerializer.loads"><a class="viewcode-back" href="../../pyspark.html#pyspark.PickleSerializer.loads">[docs]</a>        <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">,</span> <span class="n">encoding</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
            <span class="k">return</span> <span class="n">pickle</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>

</div></div>
<span class="k">class</span> <span class="nc">CloudPickleSerializer</span><span class="p">(</span><span class="n">PickleSerializer</span><span class="p">):</span>

    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">cloudpickle</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>


<div class="viewcode-block" id="MarshalSerializer"><a class="viewcode-back" href="../../pyspark.html#pyspark.MarshalSerializer">[docs]</a><span class="k">class</span> <span class="nc">MarshalSerializer</span><span class="p">(</span><span class="n">FramedSerializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Serializes objects using Python&#39;s Marshal serializer:</span>

<span class="sd">        http://docs.python.org/2/library/marshal.html</span>

<span class="sd">    This serializer is faster than PickleSerializer but supports fewer datatypes.</span>
<span class="sd">    &quot;&quot;&quot;</span>

<div class="viewcode-block" id="MarshalSerializer.dumps"><a class="viewcode-back" href="../../pyspark.html#pyspark.MarshalSerializer.dumps">[docs]</a>    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">marshal</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>
</div>
<div class="viewcode-block" id="MarshalSerializer.loads"><a class="viewcode-back" href="../../pyspark.html#pyspark.MarshalSerializer.loads">[docs]</a>    <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">marshal</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>

</div></div>
<span class="k">class</span> <span class="nc">AutoSerializer</span><span class="p">(</span><span class="n">FramedSerializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Choose marshal or pickle as serialization protocol automatically</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="n">FramedSerializer</span><span class="o">.</span><span class="n">__init__</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">_type</span> <span class="o">=</span> <span class="bp">None</span>

    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_type</span> <span class="ow">is</span> <span class="ow">not</span> <span class="bp">None</span><span class="p">:</span>
            <span class="k">return</span> <span class="n">b</span><span class="s">&#39;P&#39;</span> <span class="o">+</span> <span class="n">pickle</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">)</span>
        <span class="k">try</span><span class="p">:</span>
            <span class="k">return</span> <span class="n">b</span><span class="s">&#39;M&#39;</span> <span class="o">+</span> <span class="n">marshal</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>
        <span class="k">except</span> <span class="ne">Exception</span><span class="p">:</span>
            <span class="bp">self</span><span class="o">.</span><span class="n">_type</span> <span class="o">=</span> <span class="n">b</span><span class="s">&#39;P&#39;</span>
            <span class="k">return</span> <span class="n">b</span><span class="s">&#39;P&#39;</span> <span class="o">+</span> <span class="n">pickle</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="n">_type</span> <span class="o">=</span> <span class="n">obj</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
        <span class="k">if</span> <span class="n">_type</span> <span class="o">==</span> <span class="n">b</span><span class="s">&#39;M&#39;</span><span class="p">:</span>
            <span class="k">return</span> <span class="n">marshal</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">obj</span><span class="p">[</span><span class="mi">1</span><span class="p">:])</span>
        <span class="k">elif</span> <span class="n">_type</span> <span class="o">==</span> <span class="n">b</span><span class="s">&#39;P&#39;</span><span class="p">:</span>
            <span class="k">return</span> <span class="n">pickle</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">obj</span><span class="p">[</span><span class="mi">1</span><span class="p">:])</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="s">&quot;invalid sevialization type: </span><span class="si">%s</span><span class="s">&quot;</span> <span class="o">%</span> <span class="n">_type</span><span class="p">)</span>


<span class="k">class</span> <span class="nc">CompressedSerializer</span><span class="p">(</span><span class="n">FramedSerializer</span><span class="p">):</span>
    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Compress the serialized data</span>
<span class="sd">    &quot;&quot;&quot;</span>
    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">serializer</span><span class="p">):</span>
        <span class="n">FramedSerializer</span><span class="o">.</span><span class="n">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span>
        <span class="k">assert</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">serializer</span><span class="p">,</span> <span class="n">FramedSerializer</span><span class="p">),</span> <span class="s">&quot;serializer must be a FramedSerializer&quot;</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span> <span class="o">=</span> <span class="n">serializer</span>

    <span class="k">def</span> <span class="nf">dumps</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="n">zlib</span><span class="o">.</span><span class="n">compress</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="o">.</span><span class="n">dumps</span><span class="p">(</span><span class="n">obj</span><span class="p">),</span> <span class="mi">1</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">obj</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">zlib</span><span class="o">.</span><span class="n">decompress</span><span class="p">(</span><span class="n">obj</span><span class="p">))</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;CompressedSerializer(</span><span class="si">%s</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">serializer</span>


<span class="k">class</span> <span class="nc">UTF8Deserializer</span><span class="p">(</span><span class="n">Serializer</span><span class="p">):</span>

    <span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Deserializes streams written by String.getBytes.</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">use_unicode</span><span class="o">=</span><span class="bp">True</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">use_unicode</span> <span class="o">=</span> <span class="n">use_unicode</span>

    <span class="k">def</span> <span class="nf">loads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="n">length</span> <span class="o">=</span> <span class="n">read_int</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>
        <span class="k">if</span> <span class="n">length</span> <span class="o">==</span> <span class="n">SpecialLengths</span><span class="o">.</span><span class="n">END_OF_DATA_SECTION</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">EOFError</span>
        <span class="k">elif</span> <span class="n">length</span> <span class="o">==</span> <span class="n">SpecialLengths</span><span class="o">.</span><span class="n">NULL</span><span class="p">:</span>
            <span class="k">return</span> <span class="bp">None</span>
        <span class="n">s</span> <span class="o">=</span> <span class="n">stream</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="n">length</span><span class="p">)</span>
        <span class="k">return</span> <span class="n">s</span><span class="o">.</span><span class="n">decode</span><span class="p">(</span><span class="s">&quot;utf-8&quot;</span><span class="p">)</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">use_unicode</span> <span class="k">else</span> <span class="n">s</span>

    <span class="k">def</span> <span class="nf">load_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">try</span><span class="p">:</span>
            <span class="k">while</span> <span class="bp">True</span><span class="p">:</span>
                <span class="k">yield</span> <span class="bp">self</span><span class="o">.</span><span class="n">loads</span><span class="p">(</span><span class="n">stream</span><span class="p">)</span>
        <span class="k">except</span> <span class="n">struct</span><span class="o">.</span><span class="n">error</span><span class="p">:</span>
            <span class="k">return</span>
        <span class="k">except</span> <span class="ne">EOFError</span><span class="p">:</span>
            <span class="k">return</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="k">return</span> <span class="s">&quot;UTF8Deserializer(</span><span class="si">%s</span><span class="s">)&quot;</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">use_unicode</span>


<span class="k">def</span> <span class="nf">read_long</span><span class="p">(</span><span class="n">stream</span><span class="p">):</span>
    <span class="n">length</span> <span class="o">=</span> <span class="n">stream</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="mi">8</span><span class="p">)</span>
    <span class="k">if</span> <span class="ow">not</span> <span class="n">length</span><span class="p">:</span>
        <span class="k">raise</span> <span class="ne">EOFError</span>
    <span class="k">return</span> <span class="n">struct</span><span class="o">.</span><span class="n">unpack</span><span class="p">(</span><span class="s">&quot;!q&quot;</span><span class="p">,</span> <span class="n">length</span><span class="p">)[</span><span class="mi">0</span><span class="p">]</span>


<span class="k">def</span> <span class="nf">write_long</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
    <span class="n">stream</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="s">&quot;!q&quot;</span><span class="p">,</span> <span class="n">value</span><span class="p">))</span>


<span class="k">def</span> <span class="nf">pack_long</span><span class="p">(</span><span class="n">value</span><span class="p">):</span>
    <span class="k">return</span> <span class="n">struct</span><span class="o">.</span><span class="n">pack</span><span class="p">(</span><span class="s">&quot;!q&quot;</span><span class="p">,</span> <span class="n">value</span><span class="p">)</span>


<span class="k">def</span> <span class="nf">read_int</span><span class="p">(</span><span class="n">stream</span><span class="p">):</span>
    <span class="n">length</span> <span class="o">=</span> <span class="n">stream</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="mi">4</span><span class="p">)</span>
    <span class="k">if</span> <span class="ow">not</span> <span class="n">length</span><span class="p">:</span>
        <span class="k">raise</span> <span class="ne">EOFError</span>
    <span class="k">return</span> <span class="n">struct</span><span class="o">.</span><span class="n">unpack</span><span class="p">(</span><span class="s">&quot;!i&quot;</span><span class="p">,</span> <span class="n">length</span><span class="p">)[</span><span class="mi">0</span><span class="p">]</span>


<span class="k">def</span> <span class="nf">write_int</span><span class="p">(</span><span class="n">value</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
    <span class="n">stream</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="s">&quot;!i&quot;</span><span class="p">,</span> <span class="n">value</span><span class="p">))</span>


<span class="k">def</span> <span class="nf">write_with_length</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
    <span class="n">write_int</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">obj</span><span class="p">),</span> <span class="n">stream</span><span class="p">)</span>
    <span class="n">stream</span><span class="o">.</span><span class="n">write</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>


<span class="k">if</span> <span class="n">__name__</span> <span class="o">==</span> <span class="s">&#39;__main__&#39;</span><span class="p">:</span>
    <span class="kn">import</span> <span class="nn">doctest</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="k">if</span> <span class="n">failure_count</span><span class="p">:</span>
        <span class="nb">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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