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   <h1>Source code for apache_beam.runners.interactive.display.display_manager</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="sd">&quot;&quot;&quot;Manages displaying pipeline graph and execution status on the frontend.</span>

 <span class="sd">This module is experimental. No backwards-compatibility guarantees.</span>
 <span class="sd">&quot;&quot;&quot;</span>

 <span class="kn">from</span> <span class="nn">__future__</span> <span class="k">import</span> <span class="n">absolute_import</span>
 <span class="kn">from</span> <span class="nn">__future__</span> <span class="k">import</span> <span class="n">division</span>
 <span class="kn">from</span> <span class="nn">__future__</span> <span class="k">import</span> <span class="n">print_function</span>

 <span class="kn">import</span> <span class="nn">collections</span>
 <span class="kn">import</span> <span class="nn">threading</span>
 <span class="kn">import</span> <span class="nn">time</span>

 <span class="kn">from</span> <span class="nn">apache_beam.runners.interactive.display</span> <span class="k">import</span> <span class="n">interactive_pipeline_graph</span>

 <span class="k">try</span><span class="p">:</span>
   <span class="kn">import</span> <span class="nn">IPython</span>  <span class="c1"># pylint: disable=import-error</span>
   <span class="c1"># _display_progress defines how outputs are printed on the frontend.</span>
   <span class="n">_display_progress</span> <span class="o">=</span> <span class="n">IPython</span><span class="o">.</span><span class="n">display</span><span class="o">.</span><span class="n">display</span>

   <span class="k">def</span> <span class="nf">_formatter</span><span class="p">(</span><span class="n">string</span><span class="p">,</span> <span class="n">pp</span><span class="p">,</span> <span class="n">cycle</span><span class="p">):</span>  <span class="c1"># pylint: disable=unused-argument</span>
     <span class="n">pp</span><span class="o">.</span><span class="n">text</span><span class="p">(</span><span class="n">string</span><span class="p">)</span>
   <span class="n">plain</span> <span class="o">=</span> <span class="n">get_ipython</span><span class="p">()</span><span class="o">.</span><span class="n">display_formatter</span><span class="o">.</span><span class="n">formatters</span><span class="p">[</span><span class="s1">&#39;text/plain&#39;</span><span class="p">]</span>  <span class="c1"># pylint: disable=undefined-variable</span>
   <span class="n">plain</span><span class="o">.</span><span class="n">for_type</span><span class="p">(</span><span class="nb">str</span><span class="p">,</span> <span class="n">_formatter</span><span class="p">)</span>

 <span class="c1"># NameError is added here because get_ipython() throws &quot;not defined&quot; NameError</span>
 <span class="c1"># if not started with IPython.</span>
 <span class="k">except</span> <span class="p">(</span><span class="ne">ImportError</span><span class="p">,</span> <span class="ne">NameError</span><span class="p">):</span>
   <span class="n">IPython</span> <span class="o">=</span> <span class="kc">None</span>
   <span class="n">_display_progress</span> <span class="o">=</span> <span class="nb">print</span>


 <div class="viewcode-block" id="DisplayManager"><a class="viewcode-back" href="../../../../../apache_beam.runners.interactive.display.display_manager.html#apache_beam.runners.interactive.display.display_manager.DisplayManager">[docs]</a><span class="k">class</span> <span class="nc">DisplayManager</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
   <span class="sd">&quot;&quot;&quot;Manages displaying pipeline graph and execution status on the frontend.&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">pipeline_proto</span><span class="p">,</span> <span class="n">pipeline_analyzer</span><span class="p">,</span> <span class="n">cache_manager</span><span class="p">,</span>
                <span class="n">pipeline_graph_renderer</span><span class="p">):</span>
     <span class="sd">&quot;&quot;&quot;Constructor of DisplayManager.</span>

 <span class="sd">    Args:</span>
 <span class="sd">      pipeline_proto: (Pipeline proto)</span>
 <span class="sd">      pipeline_analyzer: (PipelineAnalyzer) the pipeline analyzer that</span>
 <span class="sd">          corresponds to this round of execution. This will provide more</span>
 <span class="sd">          detailed informations about the pipeline</span>
 <span class="sd">      cache_manager: (interactive_runner.CacheManager) DisplayManager fetches</span>
 <span class="sd">          the latest status of pipeline execution by querying cache_manager.</span>
 <span class="sd">      pipeline_graph_renderer: (pipeline_graph_renderer.PipelineGraphRenderer)</span>
 <span class="sd">          decides how a pipeline graph is rendered.</span>
 <span class="sd">    &quot;&quot;&quot;</span>
     <span class="c1"># Every parameter except cache_manager is expected to remain constant.</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span> <span class="o">=</span> <span class="n">pipeline_analyzer</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_cache_manager</span> <span class="o">=</span> <span class="n">cache_manager</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_pipeline_graph</span> <span class="o">=</span> <span class="n">interactive_pipeline_graph</span><span class="o">.</span><span class="n">InteractivePipelineGraph</span><span class="p">(</span>
         <span class="n">pipeline_proto</span><span class="p">,</span>
         <span class="n">required_transforms</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">tl_required_trans_ids</span><span class="p">(),</span>
         <span class="n">referenced_pcollections</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">tl_referenced_pcoll_ids</span><span class="p">(),</span>
         <span class="n">cached_pcollections</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">caches_used</span><span class="p">())</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_renderer</span> <span class="o">=</span> <span class="n">pipeline_graph_renderer</span>

     <span class="c1"># _text_to_print keeps track of information to be displayed.</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_text_to_print</span> <span class="o">=</span> <span class="n">collections</span><span class="o">.</span><span class="n">OrderedDict</span><span class="p">()</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_text_to_print</span><span class="p">[</span><span class="s1">&#39;summary&#39;</span><span class="p">]</span> <span class="o">=</span> <span class="p">(</span>
         <span class="s1">&#39;Using </span><span class="si">%s</span><span class="s1"> cached PCollections</span><span class="se">\n</span><span class="s1">Executing </span><span class="si">%s</span><span class="s1"> of </span><span class="si">%s</span><span class="s1"> &#39;</span>
         <span class="s1">&#39;transforms.&#39;</span><span class="p">)</span> <span class="o">%</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">_analyzer</span><span class="o">.</span><span class="n">caches_used</span><span class="p">()),</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">_analyzer</span><span class="o">.</span><span class="n">tl_required_trans_ids</span><span class="p">())</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">_analyzer</span><span class="o">.</span><span class="n">read_cache_ids</span><span class="p">())</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">_analyzer</span><span class="o">.</span><span class="n">write_cache_ids</span><span class="p">())),</span>
             <span class="nb">len</span><span class="p">(</span><span class="n">pipeline_proto</span><span class="o">.</span><span class="n">components</span><span class="o">.</span><span class="n">transforms</span><span class="p">[</span>
                 <span class="n">pipeline_proto</span><span class="o">.</span><span class="n">root_transform_ids</span><span class="p">[</span><span class="mi">0</span><span class="p">]]</span><span class="o">.</span><span class="n">subtransforms</span><span class="p">))</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_text_to_print</span><span class="o">.</span><span class="n">update</span><span class="p">({</span>
         <span class="n">pcoll_id</span><span class="p">:</span> <span class="s2">&quot;&quot;</span> <span class="k">for</span> <span class="n">pcoll_id</span>
         <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">tl_referenced_pcoll_ids</span><span class="p">()})</span>

     <span class="c1"># _pcollection_stats maps pcoll_id to</span>
     <span class="c1"># { &#39;cache_label&#39;: cache_label, version&#39;: version, &#39;sample&#39;: pcoll_in_list }</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_pcollection_stats</span> <span class="o">=</span> <span class="p">{}</span>
     <span class="k">for</span> <span class="n">pcoll_id</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">tl_referenced_pcoll_ids</span><span class="p">():</span>
       <span class="bp">self</span><span class="o">.</span><span class="n">_pcollection_stats</span><span class="p">[</span><span class="n">pcoll_id</span><span class="p">]</span> <span class="o">=</span> <span class="p">{</span>
           <span class="s1">&#39;cache_label&#39;</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">pipeline_info</span><span class="p">()</span><span class="o">.</span><span class="n">cache_label</span><span class="p">(</span><span class="n">pcoll_id</span><span class="p">),</span>
           <span class="s1">&#39;version&#39;</span><span class="p">:</span> <span class="o">-</span><span class="mi">1</span><span class="p">,</span>
           <span class="s1">&#39;sample&#39;</span><span class="p">:</span> <span class="p">[]</span>
       <span class="p">}</span>

     <span class="bp">self</span><span class="o">.</span><span class="n">_producers</span> <span class="o">=</span> <span class="p">{}</span>
     <span class="k">for</span> <span class="n">_</span><span class="p">,</span> <span class="n">transform</span> <span class="ow">in</span> <span class="n">pipeline_proto</span><span class="o">.</span><span class="n">components</span><span class="o">.</span><span class="n">transforms</span><span class="o">.</span><span class="n">items</span><span class="p">():</span>
       <span class="k">for</span> <span class="n">pcoll_id</span> <span class="ow">in</span> <span class="n">transform</span><span class="o">.</span><span class="n">outputs</span><span class="o">.</span><span class="n">values</span><span class="p">():</span>
         <span class="k">if</span> <span class="n">pcoll_id</span> <span class="ow">not</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_producers</span> <span class="ow">or</span> <span class="s1">&#39;/&#39;</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">transform</span><span class="o">.</span><span class="n">unique_name</span><span class="p">:</span>
           <span class="bp">self</span><span class="o">.</span><span class="n">_producers</span><span class="p">[</span><span class="n">pcoll_id</span><span class="p">]</span> <span class="o">=</span> <span class="n">transform</span><span class="o">.</span><span class="n">unique_name</span>

     <span class="c1"># For periodic update.</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_lock</span> <span class="o">=</span> <span class="n">threading</span><span class="o">.</span><span class="n">Lock</span><span class="p">()</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_periodic_update</span> <span class="o">=</span> <span class="kc">False</span>

 <div class="viewcode-block" id="DisplayManager.update_display"><a class="viewcode-back" href="../../../../../apache_beam.runners.interactive.display.display_manager.html#apache_beam.runners.interactive.display.display_manager.DisplayManager.update_display">[docs]</a>  <span class="k">def</span> <span class="nf">update_display</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">force</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span>
     <span class="sd">&quot;&quot;&quot;Updates display on the frontend.</span>

 <span class="sd">    Retrieves the latest execution status by querying CacheManager and updates</span>
 <span class="sd">    display on the fronend. The assumption is that there is only one pipeline in</span>
 <span class="sd">    a cell, because it clears up everything in the cell output every update</span>
 <span class="sd">    cycle.</span>

 <span class="sd">    Args:</span>
 <span class="sd">      force: (bool) whether to force updating when no stats change happens.</span>
 <span class="sd">    &quot;&quot;&quot;</span>
     <span class="k">with</span> <span class="bp">self</span><span class="o">.</span><span class="n">_lock</span><span class="p">:</span>
       <span class="n">stats_updated</span> <span class="o">=</span> <span class="kc">False</span>

       <span class="k">for</span> <span class="n">pcoll_id</span><span class="p">,</span> <span class="n">stats</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_pcollection_stats</span><span class="o">.</span><span class="n">items</span><span class="p">():</span>
         <span class="n">cache_label</span> <span class="o">=</span> <span class="n">stats</span><span class="p">[</span><span class="s1">&#39;cache_label&#39;</span><span class="p">]</span>
         <span class="n">version</span> <span class="o">=</span> <span class="n">stats</span><span class="p">[</span><span class="s1">&#39;version&#39;</span><span class="p">]</span>

         <span class="k">if</span> <span class="n">force</span> <span class="ow">or</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_cache_manager</span><span class="o">.</span><span class="n">is_latest_version</span><span class="p">(</span>
             <span class="n">version</span><span class="p">,</span> <span class="s1">&#39;sample&#39;</span><span class="p">,</span> <span class="n">cache_label</span><span class="p">):</span>
           <span class="n">pcoll_list</span><span class="p">,</span> <span class="n">version</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_cache_manager</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="s1">&#39;sample&#39;</span><span class="p">,</span> <span class="n">cache_label</span><span class="p">)</span>
           <span class="n">stats</span><span class="p">[</span><span class="s1">&#39;sample&#39;</span><span class="p">]</span> <span class="o">=</span> <span class="n">pcoll_list</span>
           <span class="n">stats</span><span class="p">[</span><span class="s1">&#39;version&#39;</span><span class="p">]</span> <span class="o">=</span> <span class="n">version</span>
           <span class="n">stats_updated</span> <span class="o">=</span> <span class="kc">True</span>

           <span class="k">if</span> <span class="n">pcoll_id</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_analyzer</span><span class="o">.</span><span class="n">tl_referenced_pcoll_ids</span><span class="p">():</span>
             <span class="bp">self</span><span class="o">.</span><span class="n">_text_to_print</span><span class="p">[</span><span class="n">pcoll_id</span><span class="p">]</span> <span class="o">=</span> <span class="p">(</span><span class="nb">str</span><span class="p">(</span>
                 <span class="s1">&#39;</span><span class="si">%s</span><span class="s1"> produced </span><span class="si">%s</span><span class="s1">&#39;</span> <span class="o">%</span> <span class="p">(</span>
                     <span class="bp">self</span><span class="o">.</span><span class="n">_producers</span><span class="p">[</span><span class="n">pcoll_id</span><span class="p">],</span>
                     <span class="n">interactive_pipeline_graph</span><span class="o">.</span><span class="n">format_sample</span><span class="p">(</span><span class="n">pcoll_list</span><span class="p">,</span> <span class="mi">5</span><span class="p">))))</span>

       <span class="k">if</span> <span class="n">force</span> <span class="ow">or</span> <span class="n">stats_updated</span><span class="p">:</span>
         <span class="bp">self</span><span class="o">.</span><span class="n">_pipeline_graph</span><span class="o">.</span><span class="n">update_pcollection_stats</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_pcollection_stats</span><span class="p">)</span>

         <span class="k">if</span> <span class="n">IPython</span><span class="p">:</span>
           <span class="kn">from</span> <span class="nn">IPython.core</span> <span class="k">import</span> <span class="n">display</span>
           <span class="n">display</span><span class="o">.</span><span class="n">clear_output</span><span class="p">(</span><span class="kc">True</span><span class="p">)</span>
           <span class="n">rendered_graph</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_renderer</span><span class="o">.</span><span class="n">render_pipeline_graph</span><span class="p">(</span>
               <span class="bp">self</span><span class="o">.</span><span class="n">_pipeline_graph</span><span class="p">)</span>
           <span class="n">display</span><span class="o">.</span><span class="n">display</span><span class="p">(</span><span class="n">display</span><span class="o">.</span><span class="n">HTML</span><span class="p">(</span><span class="n">rendered_graph</span><span class="p">))</span>

         <span class="n">_display_progress</span><span class="p">(</span><span class="s1">&#39;Running...&#39;</span><span class="p">)</span>
         <span class="k">for</span> <span class="n">text</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_text_to_print</span><span class="o">.</span><span class="n">values</span><span class="p">():</span>
           <span class="k">if</span> <span class="n">text</span> <span class="o">!=</span> <span class="s2">&quot;&quot;</span><span class="p">:</span>
             <span class="n">_display_progress</span><span class="p">(</span><span class="n">text</span><span class="p">)</span></div>

 <div class="viewcode-block" id="DisplayManager.start_periodic_update"><a class="viewcode-back" href="../../../../../apache_beam.runners.interactive.display.display_manager.html#apache_beam.runners.interactive.display.display_manager.DisplayManager.start_periodic_update">[docs]</a>  <span class="k">def</span> <span class="nf">start_periodic_update</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
     <span class="sd">&quot;&quot;&quot;Start a thread that periodically updates the display.&quot;&quot;&quot;</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">update_display</span><span class="p">(</span><span class="kc">True</span><span class="p">)</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_periodic_update</span> <span class="o">=</span> <span class="kc">True</span>

     <span class="k">def</span> <span class="nf">_updater</span><span class="p">():</span>
       <span class="k">while</span> <span class="bp">self</span><span class="o">.</span><span class="n">_periodic_update</span><span class="p">:</span>
         <span class="bp">self</span><span class="o">.</span><span class="n">update_display</span><span class="p">()</span>
         <span class="n">time</span><span class="o">.</span><span class="n">sleep</span><span class="p">(</span><span class="o">.</span><span class="mi">02</span><span class="p">)</span>

     <span class="n">t</span> <span class="o">=</span> <span class="n">threading</span><span class="o">.</span><span class="n">Thread</span><span class="p">(</span><span class="n">target</span><span class="o">=</span><span class="n">_updater</span><span class="p">)</span>
     <span class="n">t</span><span class="o">.</span><span class="n">daemon</span> <span class="o">=</span> <span class="kc">True</span>
     <span class="n">t</span><span class="o">.</span><span class="n">start</span><span class="p">()</span></div>

 <div class="viewcode-block" id="DisplayManager.stop_periodic_update"><a class="viewcode-back" href="../../../../../apache_beam.runners.interactive.display.display_manager.html#apache_beam.runners.interactive.display.display_manager.DisplayManager.stop_periodic_update">[docs]</a>  <span class="k">def</span> <span class="nf">stop_periodic_update</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
     <span class="sd">&quot;&quot;&quot;Stop periodically updating the display.&quot;&quot;&quot;</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">update_display</span><span class="p">(</span><span class="kc">True</span><span class="p">)</span>
     <span class="bp">self</span><span class="o">.</span><span class="n">_periodic_update</span> <span class="o">=</span> <span class="kc">False</span></div></div>
 </pre></div>

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