Issue #528: Add metrics table for counting

atmo/settings.py

@@ -314,6 +314,7 @@ class Core(AWS, Celery, Constance, CSP, Configuration):
         'atmo.jobs',
         'atmo.apps.KeysAppConfig',
         'atmo.users',
+        'atmo.stats',
 
         # Third party apps
         'allauth',

atmo/stats/migrations/0001_initial.py

@@ -0,0 +1,29 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.3 on 2017-07-19 19:56
+from __future__ import unicode_literals
+
+import django.contrib.postgres.fields.jsonb
+import django.core.serializers.json
+from django.db import migrations, models
+import django.utils.timezone
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Metric',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('created_at', models.DateTimeField(blank=True, default=django.utils.timezone.now, editable=False)),
+                ('key', models.CharField(help_text='Name of the metric being recorded', max_length=100)),
+                ('value', models.PositiveIntegerField(help_text='Integer value of the metric')),
+                ('data', django.contrib.postgres.fields.jsonb.JSONField(blank=True, encoder=django.core.serializers.json.DjangoJSONEncoder, help_text='Extra data about this metric', null=True)),
+            ],
+        ),
+    ]

atmo/stats/models.py

@@ -0,0 +1,53 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, you can obtain one at http://mozilla.org/MPL/2.0/.
+from django.contrib.postgres.fields import JSONField
+from django.core.serializers.json import DjangoJSONEncoder
+from django.db import models
+from django.utils import timezone
+
+
+class Metric(models.Model):
+    created_at = models.DateTimeField(
+        editable=False,
+        blank=True,
+        default=timezone.now,
+    )
+    key = models.CharField(
+        max_length=100,
+        help_text='Name of the metric being recorded',
+    )
+    value = models.PositiveIntegerField(
+        help_text='Integer value of the metric',
+    )
+    data = JSONField(
+        encoder=DjangoJSONEncoder,
+        blank=True,
+        null=True,
+        help_text='Extra data about this metric',
+    )
+
+    @classmethod
+    def record(cls, key, value=1, **kwargs):
+        """
+        Create a new entry in the ``Metric`` table.
+
+        :param key:
+            The metric key name.
+
+        :param value:
+            The metric value as an integer.
+
+        :param data:
+            Any extra data to be stored with this record as a dictionary.
+
+        """
+        created_at = kwargs.pop('created_at', None) or timezone.now()
+        data = kwargs.pop('data', None)
+
+        cls.objects.create(
+            created_at=created_at,
+            key=key,
+            value=value,
+            data=data
+        )

tests/test_stats.py

@@ -0,0 +1,32 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, you can obtain one at http://mozilla.org/MPL/2.0/.
+from atmo.stats.models import Metric
+
+
+def test_metrics_record(now, one_hour_ago):
+    Metric.record('metric-key-1')
+    Metric.record('metric-key-2', 500)
+    Metric.record('metric-key-3', data={'other-value': 'test'})
+    Metric.record('metric-key-4', created_at=one_hour_ago,
+                  data={'other-value-2': 100})
+
+    m = Metric.objects.get(key='metric-key-1')
+    assert m.value == 1
+    assert m.created_at.replace(microsecond=0) == now
+    assert m.data is None
+
+    m = Metric.objects.get(key='metric-key-2')
+    assert m.value == 500
+    assert m.created_at.replace(microsecond=0) == now
+    assert m.data is None
+
+    m = Metric.objects.get(key='metric-key-3')
+    assert m.value == 1
+    assert m.created_at.replace(microsecond=0) == now
+    assert m.data == {'other-value': 'test'}
+
+    m = Metric.objects.get(key='metric-key-4')
+    assert m.value == 1
+    assert m.created_at.replace(microsecond=0) == one_hour_ago
+    assert m.data == {'other-value-2': 100}