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<h1>Source code for apache_beam.coders.row_coder</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 &quot;License&quot;); 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 &quot;AS IS&quot; 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="c1"># pytype: skip-file</span>
<span class="kn">from</span> <span class="nn">__future__</span> <span class="kn">import</span> <span class="n">absolute_import</span>
<span class="kn">import</span> <span class="nn">itertools</span>
<span class="kn">from</span> <span class="nn">array</span> <span class="kn">import</span> <span class="n">array</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coder_impl</span> <span class="kn">import</span> <span class="n">StreamCoderImpl</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">BytesCoder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">Coder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">FastCoder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">FloatCoder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">IterableCoder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">StrUtf8Coder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">TupleCoder</span>
<span class="kn">from</span> <span class="nn">apache_beam.coders.coders</span> <span class="kn">import</span> <span class="n">VarIntCoder</span>
<span class="kn">from</span> <span class="nn">apache_beam.portability</span> <span class="kn">import</span> <span class="n">common_urns</span>
<span class="kn">from</span> <span class="nn">apache_beam.portability.api</span> <span class="kn">import</span> <span class="n">schema_pb2</span>
<span class="kn">from</span> <span class="nn">apache_beam.typehints.schemas</span> <span class="kn">import</span> <span class="n">named_tuple_from_schema</span>
<span class="kn">from</span> <span class="nn">apache_beam.typehints.schemas</span> <span class="kn">import</span> <span class="n">named_tuple_to_schema</span>
<span class="n">__all__</span> <span class="o">=</span> <span class="p">[</span><span class="s2">&quot;RowCoder&quot;</span><span class="p">]</span>
<div class="viewcode-block" id="RowCoder"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder">[docs]</a><span class="k">class</span> <span class="nc">RowCoder</span><span class="p">(</span><span class="n">FastCoder</span><span class="p">):</span>
<span class="sd">&quot;&quot;&quot; Coder for `typing.NamedTuple` instances.</span>
<span class="sd"> Implements the beam:coder:row:v1 standard coder spec.</span>
<span class="sd"> &quot;&quot;&quot;</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">schema</span><span class="p">):</span>
<span class="sd">&quot;&quot;&quot;Initializes a :class:`RowCoder`.</span>
<span class="sd"> Args:</span>
<span class="sd"> schema (apache_beam.portability.api.schema_pb2.Schema): The protobuf</span>
<span class="sd"> representation of the schema of the data that the RowCoder will be used</span>
<span class="sd"> to encode/decode.</span>
<span class="sd"> &quot;&quot;&quot;</span>
<span class="bp">self</span><span class="o">.</span><span class="n">schema</span> <span class="o">=</span> <span class="n">schema</span>
<span class="bp">self</span><span class="o">.</span><span class="n">components</span> <span class="o">=</span> <span class="p">[</span>
<span class="n">RowCoder</span><span class="o">.</span><span class="n">coder_from_type</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">type</span><span class="p">)</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="o">.</span><span class="n">fields</span>
<span class="p">]</span>
<span class="k">def</span> <span class="nf">_create_impl</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="n">RowCoderImpl</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">)</span>
<div class="viewcode-block" id="RowCoder.is_deterministic"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.is_deterministic">[docs]</a> <span class="k">def</span> <span class="nf">is_deterministic</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="nb">all</span><span class="p">(</span><span class="n">c</span><span class="o">.</span><span class="n">is_deterministic</span><span class="p">()</span> <span class="k">for</span> <span class="n">c</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">)</span></div>
<div class="viewcode-block" id="RowCoder.to_type_hint"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.to_type_hint">[docs]</a> <span class="k">def</span> <span class="nf">to_type_hint</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
<span class="k">return</span> <span class="n">named_tuple_from_schema</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="p">)</span></div>
<div class="viewcode-block" id="RowCoder.as_cloud_object"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.as_cloud_object">[docs]</a> <span class="k">def</span> <span class="nf">as_cloud_object</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">coders_context</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span>
<span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s2">&quot;as_cloud_object not supported for RowCoder&quot;</span><span class="p">)</span></div>
<span class="fm">__hash__</span> <span class="o">=</span> <span class="kc">None</span> <span class="c1"># type: ignore[assignment]</span>
<span class="k">def</span> <span class="fm">__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">type</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">==</span> <span class="nb">type</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">schema</span> <span class="o">==</span> <span class="n">other</span><span class="o">.</span><span class="n">schema</span>
<div class="viewcode-block" id="RowCoder.to_runner_api_parameter"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.to_runner_api_parameter">[docs]</a> <span class="k">def</span> <span class="nf">to_runner_api_parameter</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">unused_context</span><span class="p">):</span>
<span class="k">return</span> <span class="p">(</span><span class="n">common_urns</span><span class="o">.</span><span class="n">coders</span><span class="o">.</span><span class="n">ROW</span><span class="o">.</span><span class="n">urn</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="p">,</span> <span class="p">[])</span></div>
<div class="viewcode-block" id="RowCoder.from_runner_api_parameter"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.from_runner_api_parameter">[docs]</a> <span class="nd">@Coder</span><span class="o">.</span><span class="n">register_urn</span><span class="p">(</span><span class="n">common_urns</span><span class="o">.</span><span class="n">coders</span><span class="o">.</span><span class="n">ROW</span><span class="o">.</span><span class="n">urn</span><span class="p">,</span> <span class="n">schema_pb2</span><span class="o">.</span><span class="n">Schema</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">from_runner_api_parameter</span><span class="p">(</span><span class="n">payload</span><span class="p">,</span> <span class="n">components</span><span class="p">,</span> <span class="n">unused_context</span><span class="p">):</span>
<span class="k">return</span> <span class="n">RowCoder</span><span class="p">(</span><span class="n">payload</span><span class="p">)</span></div>
<div class="viewcode-block" id="RowCoder.from_type_hint"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.from_type_hint">[docs]</a> <span class="nd">@staticmethod</span>
<span class="k">def</span> <span class="nf">from_type_hint</span><span class="p">(</span><span class="n">named_tuple_type</span><span class="p">,</span> <span class="n">registry</span><span class="p">):</span>
<span class="k">return</span> <span class="n">RowCoder</span><span class="p">(</span><span class="n">named_tuple_to_schema</span><span class="p">(</span><span class="n">named_tuple_type</span><span class="p">))</span></div>
<div class="viewcode-block" id="RowCoder.coder_from_type"><a class="viewcode-back" href="../../../apache_beam.coders.row_coder.html#apache_beam.coders.row_coder.RowCoder.coder_from_type">[docs]</a> <span class="nd">@staticmethod</span>
<span class="k">def</span> <span class="nf">coder_from_type</span><span class="p">(</span><span class="n">field_type</span><span class="p">):</span>
<span class="n">type_info</span> <span class="o">=</span> <span class="n">field_type</span><span class="o">.</span><span class="n">WhichOneof</span><span class="p">(</span><span class="s2">&quot;type_info&quot;</span><span class="p">)</span>
<span class="k">if</span> <span class="n">type_info</span> <span class="o">==</span> <span class="s2">&quot;atomic_type&quot;</span><span class="p">:</span>
<span class="k">if</span> <span class="n">field_type</span><span class="o">.</span><span class="n">atomic_type</span> <span class="ow">in</span> <span class="p">(</span><span class="n">schema_pb2</span><span class="o">.</span><span class="n">INT32</span><span class="p">,</span>
<span class="n">schema_pb2</span><span class="o">.</span><span class="n">INT64</span><span class="p">):</span>
<span class="k">return</span> <span class="n">VarIntCoder</span><span class="p">()</span>
<span class="k">elif</span> <span class="n">field_type</span><span class="o">.</span><span class="n">atomic_type</span> <span class="o">==</span> <span class="n">schema_pb2</span><span class="o">.</span><span class="n">DOUBLE</span><span class="p">:</span>
<span class="k">return</span> <span class="n">FloatCoder</span><span class="p">()</span>
<span class="k">elif</span> <span class="n">field_type</span><span class="o">.</span><span class="n">atomic_type</span> <span class="o">==</span> <span class="n">schema_pb2</span><span class="o">.</span><span class="n">STRING</span><span class="p">:</span>
<span class="k">return</span> <span class="n">StrUtf8Coder</span><span class="p">()</span>
<span class="k">elif</span> <span class="n">type_info</span> <span class="o">==</span> <span class="s2">&quot;array_type&quot;</span><span class="p">:</span>
<span class="k">return</span> <span class="n">IterableCoder</span><span class="p">(</span>
<span class="n">RowCoder</span><span class="o">.</span><span class="n">coder_from_type</span><span class="p">(</span><span class="n">field_type</span><span class="o">.</span><span class="n">array_type</span><span class="o">.</span><span class="n">element_type</span><span class="p">))</span>
<span class="c1"># The Java SDK supports several more types, but the coders are not yet</span>
<span class="c1"># standard, and are not implemented in Python.</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span>
<span class="s2">&quot;Encountered a type that is not currently supported by RowCoder: </span><span class="si">%s</span><span class="s2">&quot;</span> <span class="o">%</span>
<span class="n">field_type</span><span class="p">)</span></div></div>
<span class="k">class</span> <span class="nc">RowCoderImpl</span><span class="p">(</span><span class="n">StreamCoderImpl</span><span class="p">):</span>
<span class="sd">&quot;&quot;&quot;For internal use only; no backwards-compatibility guarantees.&quot;&quot;&quot;</span>
<span class="n">SIZE_CODER</span> <span class="o">=</span> <span class="n">VarIntCoder</span><span class="p">()</span><span class="o">.</span><span class="n">get_impl</span><span class="p">()</span>
<span class="n">NULL_MARKER_CODER</span> <span class="o">=</span> <span class="n">BytesCoder</span><span class="p">()</span><span class="o">.</span><span class="n">get_impl</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">schema</span><span class="p">,</span> <span class="n">components</span><span class="p">):</span>
<span class="bp">self</span><span class="o">.</span><span class="n">schema</span> <span class="o">=</span> <span class="n">schema</span>
<span class="bp">self</span><span class="o">.</span><span class="n">constructor</span> <span class="o">=</span> <span class="n">named_tuple_from_schema</span><span class="p">(</span><span class="n">schema</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">components</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">c</span><span class="o">.</span><span class="n">get_impl</span><span class="p">()</span> <span class="k">for</span> <span class="n">c</span> <span class="ow">in</span> <span class="n">components</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">has_nullable_fields</span> <span class="o">=</span> <span class="nb">any</span><span class="p">(</span>
<span class="n">field</span><span class="o">.</span><span class="n">type</span><span class="o">.</span><span class="n">nullable</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="o">.</span><span class="n">fields</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">encode_to_stream</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">out</span><span class="p">,</span> <span class="n">nested</span><span class="p">):</span>
<span class="n">nvals</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="o">.</span><span class="n">fields</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">SIZE_CODER</span><span class="o">.</span><span class="n">encode_to_stream</span><span class="p">(</span><span class="n">nvals</span><span class="p">,</span> <span class="n">out</span><span class="p">,</span> <span class="kc">True</span><span class="p">)</span>
<span class="n">attrs</span> <span class="o">=</span> <span class="p">[</span><span class="nb">getattr</span><span class="p">(</span><span class="n">value</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="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="o">.</span><span class="n">fields</span><span class="p">]</span>
<span class="n">words</span> <span class="o">=</span> <span class="n">array</span><span class="p">(</span><span class="s1">&#39;B&#39;</span><span class="p">)</span>
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">has_nullable_fields</span><span class="p">:</span>
<span class="n">nulls</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">attr</span> <span class="ow">is</span> <span class="kc">None</span> <span class="k">for</span> <span class="n">attr</span> <span class="ow">in</span> <span class="n">attrs</span><span class="p">)</span>
<span class="k">if</span> <span class="nb">any</span><span class="p">(</span><span class="n">nulls</span><span class="p">):</span>
<span class="n">words</span> <span class="o">=</span> <span class="n">array</span><span class="p">(</span><span class="s1">&#39;B&#39;</span><span class="p">,</span> <span class="n">itertools</span><span class="o">.</span><span class="n">repeat</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="p">(</span><span class="n">nvals</span><span class="o">+</span><span class="mi">7</span><span class="p">)</span><span class="o">//</span><span class="mi">8</span><span class="p">))</span>
<span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">is_null</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">nulls</span><span class="p">):</span>
<span class="n">words</span><span class="p">[</span><span class="n">i</span><span class="o">//</span><span class="mi">8</span><span class="p">]</span> <span class="o">|=</span> <span class="n">is_null</span> <span class="o">&lt;&lt;</span> <span class="p">(</span><span class="n">i</span> <span class="o">%</span> <span class="mi">8</span><span class="p">)</span>
<span class="bp">self</span><span class="o">.</span><span class="n">NULL_MARKER_CODER</span><span class="o">.</span><span class="n">encode_to_stream</span><span class="p">(</span><span class="n">words</span><span class="o">.</span><span class="n">tostring</span><span class="p">(),</span> <span class="n">out</span><span class="p">,</span> <span class="kc">True</span><span class="p">)</span>
<span class="k">for</span> <span class="n">c</span><span class="p">,</span> <span class="n">field</span><span class="p">,</span> <span class="n">attr</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">schema</span><span class="o">.</span><span class="n">fields</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span>
<span class="k">if</span> <span class="n">attr</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">field</span><span class="o">.</span><span class="n">type</span><span class="o">.</span><span class="n">nullable</span><span class="p">:</span>
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span>
<span class="s2">&quot;Attempted to encode null for non-nullable field </span><span class="se">\&quot;</span><span class="si">{}</span><span class="se">\&quot;</span><span class="s2">.&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span>
<span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">))</span>
<span class="k">continue</span>
<span class="n">c</span><span class="o">.</span><span class="n">encode_to_stream</span><span class="p">(</span><span class="n">attr</span><span class="p">,</span> <span class="n">out</span><span class="p">,</span> <span class="kc">True</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">decode_from_stream</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">in_stream</span><span class="p">,</span> <span class="n">nested</span><span class="p">):</span>
<span class="n">nvals</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">SIZE_CODER</span><span class="o">.</span><span class="n">decode_from_stream</span><span class="p">(</span><span class="n">in_stream</span><span class="p">,</span> <span class="kc">True</span><span class="p">)</span>
<span class="n">words</span> <span class="o">=</span> <span class="n">array</span><span class="p">(</span><span class="s1">&#39;B&#39;</span><span class="p">)</span>
<span class="n">words</span><span class="o">.</span><span class="n">fromstring</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">NULL_MARKER_CODER</span><span class="o">.</span><span class="n">decode_from_stream</span><span class="p">(</span><span class="n">in_stream</span><span class="p">,</span> <span class="kc">True</span><span class="p">))</span>
<span class="k">if</span> <span class="n">words</span><span class="p">:</span>
<span class="n">nulls</span> <span class="o">=</span> <span class="p">((</span><span class="n">words</span><span class="p">[</span><span class="n">i</span> <span class="o">//</span> <span class="mi">8</span><span class="p">]</span> <span class="o">&gt;&gt;</span> <span class="p">(</span><span class="n">i</span> <span class="o">%</span> <span class="mi">8</span><span class="p">))</span> <span class="o">&amp;</span> <span class="mh">0x01</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="n">nvals</span><span class="p">))</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">nulls</span> <span class="o">=</span> <span class="n">itertools</span><span class="o">.</span><span class="n">repeat</span><span class="p">(</span><span class="kc">False</span><span class="p">,</span> <span class="n">nvals</span><span class="p">)</span>
<span class="c1"># If this coder&#39;s schema has more attributes than the encoded value, then</span>
<span class="c1"># the schema must have changed. Populate the unencoded fields with nulls.</span>
<span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">)</span> <span class="o">&gt;</span> <span class="n">nvals</span><span class="p">:</span>
<span class="n">nulls</span> <span class="o">=</span> <span class="n">itertools</span><span class="o">.</span><span class="n">chain</span><span class="p">(</span>
<span class="n">nulls</span><span class="p">,</span>
<span class="n">itertools</span><span class="o">.</span><span class="n">repeat</span><span class="p">(</span><span class="kc">True</span><span class="p">,</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">)</span> <span class="o">-</span> <span class="n">nvals</span><span class="p">))</span>
<span class="c1"># Note that if this coder&#39;s schema has *fewer* attributes than the encoded</span>
<span class="c1"># value, we just need to ignore the additional values, which will occur</span>
<span class="c1"># here because we only decode as many values as we have coders for.</span>
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">constructor</span><span class="p">(</span><span class="o">*</span><span class="p">(</span>
<span class="kc">None</span> <span class="k">if</span> <span class="n">is_null</span> <span class="k">else</span> <span class="n">c</span><span class="o">.</span><span class="n">decode_from_stream</span><span class="p">(</span><span class="n">in_stream</span><span class="p">,</span> <span class="kc">True</span><span class="p">)</span>
<span class="k">for</span> <span class="n">c</span><span class="p">,</span> <span class="n">is_null</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">,</span> <span class="n">nulls</span><span class="p">)))</span>
<span class="k">def</span> <span class="nf">_make_value_coder</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">nulls</span><span class="o">=</span><span class="n">itertools</span><span class="o">.</span><span class="n">repeat</span><span class="p">(</span><span class="kc">False</span><span class="p">)):</span>
<span class="n">components</span> <span class="o">=</span> <span class="p">[</span>
<span class="n">component</span> <span class="k">for</span> <span class="n">component</span><span class="p">,</span> <span class="n">is_null</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">components</span><span class="p">,</span> <span class="n">nulls</span><span class="p">)</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">is_null</span>
<span class="p">]</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">has_nullable_fields</span> <span class="k">else</span> <span class="bp">self</span><span class="o">.</span><span class="n">components</span>
<span class="k">return</span> <span class="n">TupleCoder</span><span class="p">(</span><span class="n">components</span><span class="p">)</span><span class="o">.</span><span class="n">get_impl</span><span class="p">()</span>
</pre></div>
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