Add a Diaper Change amounts report

dashboard/templates/dashboard/child_button_group.html

@@ -16,6 +16,7 @@
                 aria-haspopup="true"
                 aria-expanded="false"><i class="icon icon-graph" aria-hidden="true"></i></button>
         <div class="dropdown-menu" aria-labelledby="reports-dropdown">
+            <a class="dropdown-item" href="{% url 'reports:report-diaperchange-amounts-child' object.slug %}">{% trans "Diaper Change Amounts" %}</a>
             <a class="dropdown-item" href="{% url 'reports:report-diaperchange-types-child' object.slug %}">{% trans "Diaper Change Types" %}</a>
             <a class="dropdown-item" href="{% url 'reports:report-diaperchange-lifetimes-child' object.slug %}">{% trans "Diaper Lifetimes" %}</a>
             <a class="dropdown-item" href="{% url 'reports:report-feeding-amounts-child' object.slug %}">{% trans "Feeding Amounts" %}</a>

reports/graphs/__init__.py

@@ -1,3 +1,4 @@
+from .diaperchange_amounts import diaperchange_amounts  # NOQA
 from .diaperchange_lifetimes import diaperchange_lifetimes  # NOQA
 from .diaperchange_types import diaperchange_types  # NOQA
 from .feeding_amounts import feeding_amounts  # NOQA

reports/graphs/diaperchange_amounts.py

@@ -0,0 +1,46 @@
+# -*- coding: utf-8 -*-
+from django.utils import timezone
+from django.utils.translation import gettext as _
+
+import plotly.offline as plotly
+import plotly.graph_objs as go
+
+from reports import utils
+
+
+def diaperchange_amounts(instances):
+    """
+    Create a graph showing daily diaper change amounts over time.
+    :param instances: a QuerySet of DiaperChange instances.
+    :returns: a tuple of the the graph's html and javascript.
+    """
+    totals = {}
+    for instance in instances:
+        time_local = timezone.localtime(instance.time)
+        date = time_local.date()
+        if date not in totals.keys():
+            totals[date] = 0
+        totals[date] += instance.amount or 0
+
+    amounts = [round(amount, 2) for amount in totals.values()]
+    trace = go.Bar(
+        name=_('Diaper change amount'),
+        x=list(totals.keys()),
+        y=amounts,
+        hoverinfo='text',
+        textposition='outside',
+        text=amounts
+    )
+
+    layout_args = utils.default_graph_layout_options()
+    layout_args['title'] = _('<b>Diaper Change Amounts</b>')
+    layout_args['xaxis']['title'] = _('Date')
+    layout_args['xaxis']['rangeselector'] = utils.rangeselector_date()
+    layout_args['yaxis']['title'] = _('Change amount')
+
+    fig = go.Figure({
+        'data': [trace],
+        'layout': go.Layout(**layout_args)
+    })
+    output = plotly.plot(fig, output_type='div', include_plotlyjs=False)
+    return utils.split_graph_output(output)

reports/templates/reports/diaperchange_amounts.html

@@ -0,0 +1,9 @@
+{% extends 'reports/report_base.html' %}
+{% load i18n %}
+
+{% block title %}{% trans "Diaper Amounts" %} - {{ object }}{% endblock %}
+
+{% block breadcrumbs %}
+    {{ block.super }}
+    <li class="breadcrumb-item active" aria-current="page">{% trans "Diaper Amounts" %}</li>
+{% endblock %}

reports/tests/tests_views.py

@@ -33,6 +33,8 @@ class ViewsTestCase(TestCase):
         child = models.Child.objects.first()
         base_url = '/children/{}/reports'.format(child.slug)
 
+        page = self.c.get('{}/changes/amounts/'.format(base_url))
+        self.assertEqual(page.status_code, 200)
         page = self.c.get('{}/changes/lifetimes/'.format(base_url))
         self.assertEqual(page.status_code, 200)
         page = self.c.get('{}/changes/types/'.format(base_url))

reports/urls.py

@@ -6,6 +6,11 @@ from . import views
 app_name = 'reports'
 
 urlpatterns = [
+    path(
+        'children/<slug:slug>/reports/changes/amounts/',
+        views.DiaperChangeAmounts.as_view(),
+        name='report-diaperchange-amounts-child'
+    ),
     path(
         'children/<slug:slug>/reports/changes/lifetimes/',
         views.DiaperChangeLifetimesChildReport.as_view(),

reports/views.py

@@ -7,6 +7,24 @@ from core import models
 from . import graphs
 
 
+class DiaperChangeAmounts(PermissionRequired403Mixin, DetailView):
+    """
+    Graph of diaper "amounts" - measurements of urine output.
+    """
+    model = models.Child
+    permission_required = ('core.view_child',)
+    template_name = 'reports/diaperchange_amounts.html'
+
+    def get_context_data(self, **kwargs):
+        context = super(DiaperChangeAmounts, self).get_context_data(**kwargs)
+        child = context['object']
+        changes = models.DiaperChange.objects.filter(child=child, amount__gt=0)
+        if changes and changes.count() > 0:
+            context['html'], context['js'] = \
+                graphs.diaperchange_amounts(changes)
+        return context
+
+
 class DiaperChangeLifetimesChildReport(PermissionRequired403Mixin, DetailView):
     """
     Graph of diaper "lifetimes" - time between diaper changes.