Add display of README files for webapp

For each webapp when a README is registered in the database, I read the
file stored in the media directory and convert it using the mistune
library from markdown into HTML. I updated the dockerfile to be used in
the Django container as well.
Signed-off-by: Matthieu Berjon <matthieu.berjon@inria.fr>

django/Dockerfile

@@ -5,7 +5,7 @@ RUN echo "deb http://ftp.debian.org/debian stretch-backports main" \
       >> /etc/apt/sources.list.d/stretch.list
 
 RUN apt-get update && apt-get -t stretch-backports install -y \
-      python3-django python3-django-allauth
+      python3-django python3-django-allauth python3-mistune
 
 RUN apt-get install -y  mysql-server default-libmysqlclient-dev \
   nginx-light zip	python3-dev python3-pip python3-mysqldb \

django/allgo/main/templatetags/markdownify.py

+from django import template
+import mistune
+
+
+register = template.Library()
+
+
+@register.filter
+def markdown(value):
+    """ Convert markdown content into HTML. """
+    markdown = mistune.Markdown()
+    return markdown(value)

django/allgo/main/views.py

+from django.conf import settings
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.shortcuts import render, get_object_or_404
 from django.urls import reverse
@@ -6,11 +7,15 @@ from django.views.generic import (
         DetailView,
         UpdateView,
         )
+import os
 
 from .models import Webapp, Job, AllgoUser
 
 
 def index(request):
+    """
+    Do nothing specific just return a specific template
+    """
     return render(request, "home.html")
 
 
@@ -44,12 +49,36 @@ class WebappDetail(DetailView):
     context_object_name = 'webapp'
 
     def get_object(self):
+        """recover data according the docker_name rather than the ID."""
         data = self.kwargs.get('docker_name', None)
         queryset = get_object_or_404(Webapp, docker_name=data)
         return queryset
 
+    def get_context_data(self, **kwargs):
+        """Recover the README file if exist and convert it from markdown to
+        HTML
+        """
+        context = super(WebappDetail, self).get_context_data(**kwargs)
+
+        # Check if a readme is declared in the database
+        if self.object.readme:
+            readme_file = os.path.join(
+                    settings.MEDIA_ROOT,
+                    self.object.docker_name,
+                    'Readme')
+            with open(readme_file, 'r') as md_data:
+                print(md_data)
+                context['readme'] = md_data.read()
+        else:
+            readme_file = None
+
+        return context
+
 
 class JobList(LoginRequiredMixin, ListView):
+    """
+    Display the list of jobs for a given identified user
+    """
     model = Job
     pattern_name = 'job_list'
     template_name = 'job_list.html'
@@ -58,6 +87,7 @@ class JobList(LoginRequiredMixin, ListView):
     redirect_field_name = 'redirect_to'
 
     def get_queryset(self):
+        """Filter jobs for a given user"""
         queryset = Job.objects.filter(user_id=self.request.user.id)
         return queryset
 

django/allgo/templates/webapp_detail.html

 {% extends "base.html" %}
+{% load markdownify %}
 
 {% block title %}{{ webapp.name }}{% endblock %}
 
 {% block content %}
 <h2>{{ webapp.name }}</h2>
 
-<p>{{ webapp.description }}</p>
+{% if readme %}
+  {{ readme | markdown | safe }}
+{% else %}
+  <p>No description available</p>
+{% endif %}
 
 {% endblock %}