API: Add stats host filter for 'gt >' and 'lt <'

This provides the ability to search for hosts based on their stats.

For example:

- return hosts with no changes: /api/v1/hosts?changed__lt=1
- return hosts with failures: /api/v1/hosts?failed__gt=0
- return hosts with unreachable tasks: /api/v1/hosts?unreachable__gt=0

Change-Id: Iccd74c3e419fdd52b8305505335f57d599eec1ee

ara/api/filters.py

@@ -126,6 +126,18 @@ class HostFilter(BaseFilter):
     playbook = django_filters.NumberFilter(field_name="playbook__id", lookup_expr="exact")
     name = django_filters.CharFilter(field_name="name", lookup_expr="icontains")
 
+    # For example: /api/v1/hosts/failed__gt=0 to return hosts with 1 failure or more
+    changed__gt = django_filters.NumberFilter(field_name="changed", lookup_expr="gt")
+    changed__lt = django_filters.NumberFilter(field_name="changed", lookup_expr="lt")
+    failed__gt = django_filters.NumberFilter(field_name="failed", lookup_expr="gt")
+    failed__lt = django_filters.NumberFilter(field_name="failed", lookup_expr="lt")
+    ok__gt = django_filters.NumberFilter(field_name="ok", lookup_expr="gt")
+    ok__lt = django_filters.NumberFilter(field_name="ok", lookup_expr="lt")
+    skipped__gt = django_filters.NumberFilter(field_name="skipped", lookup_expr="gt")
+    skipped__lt = django_filters.NumberFilter(field_name="skipped", lookup_expr="lt")
+    unreachable__gt = django_filters.NumberFilter(field_name="unreachable", lookup_expr="gt")
+    unreachable__lt = django_filters.NumberFilter(field_name="unreachable", lookup_expr="lt")
+
     # fmt: off
     order = django_filters.OrderingFilter(
         fields=(

ara/api/tests/factories.py

@@ -101,6 +101,11 @@ class HostFactory(factory.DjangoModelFactory):
     facts = utils.compressed_obj(HOST_FACTS)
     name = "hostname"
     playbook = factory.SubFactory(PlaybookFactory)
+    changed = 0
+    failed = 0
+    ok = 0
+    skipped = 0
+    unreachable = 0
 
 
 class ResultFactory(factory.DjangoModelFactory):

ara/api/tests/tests_host.py

@@ -120,6 +120,32 @@ class HostTestCase(APITestCase):
         self.assertEqual(1, len(request.data["results"]))
         self.assertEqual(host.name, request.data["results"][0]["name"])
 
+    def test_get_hosts_by_stats(self):
+        # Create two hosts with different stats
+        first_host = factories.HostFactory(name="first_host", changed=2, failed=2, ok=2, skipped=2, unreachable=2)
+        second_host = factories.HostFactory(name="second_host", changed=0, failed=0, ok=0, skipped=0, unreachable=0)
+
+        # There must be two distinct hosts
+        request = self.client.get("/api/v1/hosts")
+        self.assertEqual(2, request.data["count"])
+        self.assertEqual(2, len(request.data["results"]))
+
+        statuses = ["changed", "failed", "ok", "skipped", "unreachable"]
+
+        # Searching for > should only return the first host
+        for status in statuses:
+            request = self.client.get("/api/v1/hosts?%s__gt=1" % status)
+            self.assertEqual(1, request.data["count"])
+            self.assertEqual(1, len(request.data["results"]))
+            self.assertEqual(first_host.id, request.data["results"][0]["id"])
+
+        # Searching for < should only return the second host
+        for status in statuses:
+            request = self.client.get("/api/v1/hosts?%s__lt=1" % status)
+            self.assertEqual(1, request.data["count"])
+            self.assertEqual(1, len(request.data["results"]))
+            self.assertEqual(second_host.id, request.data["results"][0]["id"])
+
     def test_get_host_by_date(self):
         host = factories.HostFactory()