Invalid policies should be ignored in the desktop endpoint (#12523)

Updated the `/desktop` endpoint to ignore invalid policies

changes/12420-handle-policies-with-invalid-queries-desktop-endpoint

@@ -0,0 +1,2 @@
+- If a policy was defined with an invalid query, the desktop endpoint should count that policy as a
+  failed policy.

server/datastore/mysql/hosts.go

@@ -2230,7 +2230,7 @@ func (ds *Datastore) FailingPoliciesCount(ctx context.Context, host *fleet.Host)
 	query := `
 		SELECT SUM(1 - pm.passes) AS n_failed
 		FROM policy_membership pm
-		WHERE pm.host_id = ?
+		WHERE pm.host_id = ? AND pm.passes IS NOT null
 		GROUP BY host_id
 	`
 

server/service/integration_enterprise_test.go

@@ -3589,3 +3589,34 @@ func (s *integrationEnterpriseTestSuite) setTokenForTest(t *testing.T, email, pa
 
 	s.token = s.getCachedUserToken(email, password)
 }
+
+func (s *integrationEnterpriseTestSuite) TestDesktopEndpointWithInvalidPolicy() {
+	t := s.T()
+
+	token := "abcd123"
+	host := createHostAndDeviceToken(t, s.ds, token)
+
+	// Create an 'invalid' global policy for host
+	admin := s.users["admin1@example.com"]
+	err := s.ds.SaveUser(context.Background(), &admin)
+	require.NoError(t, err)
+
+	policy, err := s.ds.NewGlobalPolicy(context.Background(), &admin.ID, fleet.PolicyPayload{
+		Query:       "SELECT 1 FROM table",
+		Name:        "test",
+		Description: "Some invalid Query",
+		Resolution:  "",
+		Platform:    host.Platform,
+		Critical:    false,
+	})
+	require.NoError(t, err)
+	require.NoError(t, s.ds.RecordPolicyQueryExecutions(context.Background(), host, map[uint]*bool{policy.ID: nil}, time.Now(), false))
+
+	// Any 'invalid' policies should be ignored.
+	desktopRes := fleetDesktopResponse{}
+	res := s.DoRawNoAuth("GET", "/api/latest/fleet/device/"+token+"/desktop", nil, http.StatusOK)
+	require.NoError(t, json.NewDecoder(res.Body).Decode(&desktopRes))
+	require.NoError(t, res.Body.Close())
+	require.NoError(t, desktopRes.Err)
+	require.Equal(t, uint(0), *desktopRes.FailingPolicies)
+}