Check license expiration, disable license and notify administrator (#14420)

* Check license expiration and notify administrator

model/license_test.go

@@ -116,6 +116,15 @@ func TestLicenseIsExpired(t *testing.T) {
 	assert.False(t, l1.IsExpired())
 }
 
+func TestLicenseIsPastGracePeriod(t *testing.T) {
+	l1 := License{}
+	l1.ExpiresAt = GetMillis() - LICENSE_GRACE_PERIOD - 1000
+	assert.True(t, l1.IsPastGracePeriod())
+
+	l1.ExpiresAt = GetMillis() + 1000
+	assert.False(t, l1.IsPastGracePeriod())
+}
+
 func TestLicenseIsStarted(t *testing.T) {
 	l1 := License{}
 	l1.StartsAt = GetMillis() - 1000