packages: cache package details metadata for 59 seconds

For non-logged in users cache the expensive template which calls
get_requiredby for 59 seconds, for glibc this spawns 100 queries.

Author: jelly

Diff for: packages/views/display.py

@@ -138,7 +138,8 @@ def details(request, name='', repo='', arch=''):
                 except RebuilderdStatus.DoesNotExist:
                     pass
             return render(request, 'packages/details.html', {'pkg': pkg, 'rbstatus': rbstatus,
-                          'notreproducible': rbstatus.status == RebuilderdStatus.BAD if rbstatus else False})
+                          'notreproducible': rbstatus.status == RebuilderdStatus.BAD if rbstatus else False,
+                          'cache_time': 0 if request.user.is_authenticated else 59 })
         except Package.DoesNotExist:
             # attempt a variety of fallback options before 404ing
             options = (redirect_agnostic, split_package_details,

Diff for: templates/packages/package_details.html

@@ -1,4 +1,5 @@
 {% load humanize %}
+{% load cache %}
 {% load details_link %}
 <div id="pkgdetails" class="box">
     <h2>{{ pkg.pkgname }} {{ pkg.full_version }}</h2>
@@ -213,6 +214,7 @@ <h4>Versions Elsewhere</h4>
     </table>
     </div>
 
+    {% cache cache_time package-details-metadata user.is_authenticated %}
     <div id="metadata">
         {% with deps=pkg.get_depends %}
         <div id="pkgdeps" class="listing">
@@ -251,4 +253,5 @@ <h3 title="Complete list of so-names the package links too">
             </div>
         </div>
     </div>
+    {% endcache %}
 </div>