Louis-Philippe Véronneau - pelicanhttps://veronneau.org/2019-01-23T00:00:00-05:00Migrating from Pelican 3 to Pelican 42019-01-23T00:00:00-05:002019-01-23T00:00:00-05:00Louis-Philippe Véronneautag:veronneau.org,2019-01-23:/migrating-from-pelican-3-to-pelican-4.html<p>A couple of days ago, <code>pelican</code> got updated from version <code>3.7.1</code> in testing to
<code>4.0.1</code>. Good news is that it's now written in Python 3, bad news is that
breaking changes in the main configuration file need to be made.</p>
<p>Here's two things you'll need to …</p><p>A couple of days ago, <code>pelican</code> got updated from version <code>3.7.1</code> in testing to
<code>4.0.1</code>. Good news is that it's now written in Python 3, bad news is that
breaking changes in the main configuration file need to be made.</p>
<p>Here's two things you'll need to change in <code>pelicanconf.py</code> to migrate:</p>
<p>1. <code>%s</code> in the Atom feed path needs to be replaced by either <code>{slug}</code> or
<code>{lang}</code>, depending on the variable.</p>
<p>For example:</p>
<pre>
-TAG_FEED_ATOM = 'feeds/tags/%s.atom.xml'
+TAG_FEED_ATOM = 'feeds/tags/{slug}.atom.xml'
</pre>
<p>2. <code>FEED_MAX_ITEMS</code> now needs to be an integer and not a string.</p>
<p>My previous configuration had <code>FEED_MAX_ITEMS = '20'</code> and this crashed <code>pelican</code>
with this error:</p>
<div class="highlight"><pre><span></span><code><span class="n">CRITICAL</span><span class="p">:</span> <span class="ne">TypeError</span><span class="p">:</span> <span class="s1">'<'</span> <span class="ow">not</span> <span class="n">supported</span> <span class="n">between</span> <span class="n">instances</span> <span class="n">of</span> <span class="s1">'int'</span> <span class="ow">and</span> <span class="s1">'str'</span>
<span class="n">Traceback</span> <span class="p">(</span><span class="n">most</span> <span class="n">recent</span> <span class="n">call</span> <span class="n">last</span><span class="p">):</span>
<span class="n">File</span> <span class="s2">"/usr/bin/pelican"</span><span class="p">,</span> <span class="n">line</span> <span class="mi">11</span><span class="p">,</span> <span class="ow">in</span> <span class="o"><</span><span class="n">module</span><span class="o">></span>
<span class="n">load_entry_point</span><span class="p">(</span><span class="s1">'pelican==4.0.1'</span><span class="p">,</span> <span class="s1">'console_scripts'</span><span class="p">,</span> <span class="s1">'pelican'</span><span class="p">)()</span>
<span class="n">File</span> <span class="s2">"/usr/lib/python3/dist-packages/pelican/__init__.py"</span><span class="p">,</span> <span class="n">line</span> <span class="mi">623</span><span class="p">,</span> <span class="ow">in</span> <span class="n">main</span>
<span class="n">pelican</span><span class="o">.</span><span class="n">run</span><span class="p">()</span>
<span class="n">File</span> <span class="s2">"/usr/lib/python3/dist-packages/pelican/__init__.py"</span><span class="p">,</span> <span class="n">line</span> <span class="mi">190</span><span class="p">,</span> <span class="ow">in</span> <span class="n">run</span>
<span class="n">p</span><span class="o">.</span><span class="n">generate_output</span><span class="p">(</span><span class="n">writer</span><span class="p">)</span>
<span class="n">File</span> <span class="s2">"/usr/lib/python3/dist-packages/pelican/generators.py"</span><span class="p">,</span> <span class="n">line</span> <span class="mi">688</span><span class="p">,</span> <span class="ow">in</span> <span class="n">generate_output</span>
<span class="bp">self</span><span class="o">.</span><span class="n">generate_feeds</span><span class="p">(</span><span class="n">writer</span><span class="p">)</span>
<span class="n">File</span> <span class="s2">"/usr/lib/python3/dist-packages/pelican/generators.py"</span><span class="p">,</span> <span class="n">line</span> <span class="mi">335</span><span class="p">,</span> <span class="ow">in</span> <span class="n">generate_feeds</span>
<span class="bp">self</span><span class="o">.</span><span class="n">settings</span><span class="p">[</span><span class="s1">'FEED_ALL_ATOM'</span><span class="p">])</span>
<span class="n">File</span> <span class="s2">"/usr/lib/python3/dist-packages/pelican/writers.py"</span><span class="p">,</span> <span class="n">line</span> <span class="mi">131</span><span class="p">,</span> <span class="ow">in</span> <span class="n">write_feed</span>
<span class="n">max_items</span> <span class="o">=</span> <span class="nb">min</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">settings</span><span class="p">[</span><span class="s1">'FEED_MAX_ITEMS'</span><span class="p">],</span> <span class="n">max_items</span><span class="p">)</span>
<span class="ne">TypeError</span><span class="p">:</span> <span class="s1">'<'</span> <span class="ow">not</span> <span class="n">supported</span> <span class="n">between</span> <span class="n">instances</span> <span class="n">of</span> <span class="s1">'int'</span> <span class="ow">and</span> <span class="s1">'str'</span>
</code></pre></div>
<p>This can be fixed this way:</p>
<pre>
-FEED_MAX_ITEMS = '20'
+FEED_MAX_ITEMS = 20
</pre>