func (s *collectionSizeSuite) TestCollectionOnClosedCollector(c *gc.C) {
session := s.Session.Copy()
collection := session.DB("test").C("test_collection")
err := collection.Insert(bson.M{"test": true})
c.Assert(err, jc.ErrorIsNil)
u := monitoring.NewCollectionSizeCollector("test", "test", "test", collection)
u.Close()
session.Close()
ch := make(chan prometheus.Metric, 2)
u.Collect(ch)
// read the size
select {
case <-ch:
c.Fatalf("we expected no metric")
default:
}
// read the count
select {
case <-ch:
c.Fatalf("we expected no metric")
default:
}
}
// TestCollectionOnClosedSessionGraceful closes the session directly and checks
// we handle this cleanly without panicing.
func (s *collectionSizeSuite) TestCollectionOnClosedSessionGraceful(c *gc.C) {
session := s.Session.Copy()
collection := session.DB("test").C("test_collection")
u := monitoring.NewCollectionSizeCollector("test", "test", "test", collection)
defer u.Close()
err := collection.Insert(bson.M{"test": true})
c.Assert(err, jc.ErrorIsNil)
// We close the session directly.
// As the collector has copied the session, this should not
// impact its behaviour - it should continue to monitor as usual.
session.Close()
ch := make(chan prometheus.Metric, 2)
u.Collect(ch)
// read the size
select {
case <-ch:
default:
c.Error("metric not provided by collector")
}
// read the count
select {
case <-ch:
default:
c.Error("metric not provided by collector")
}
}
func (s *collectionSizeSuite) TestCollectionSizeReporting(c *gc.C) {
collection := s.Session.DB("test").C("test_collection")
u := monitoring.NewCollectionSizeCollector("test", "test", "test", collection)
defer u.Close()
err := collection.Insert(bson.M{"test": true})
c.Assert(err, jc.ErrorIsNil)
ch := make(chan prometheus.Metric, 2)
u.Collect(ch)
var m prometheus.Metric
// read the size
select {
case m = <-ch:
default:
c.Error("metric not provided by collector")
}
var raw prometheusinternal.Metric
err = m.Write(&raw)
c.Assert(err, jc.ErrorIsNil)
cnt := raw.GetGauge()
valueOne := cnt.GetValue()
// read the count
select {
case m = <-ch:
default:
c.Error("metric not provided by collector")
}
err = m.Write(&raw)
c.Assert(err, jc.ErrorIsNil)
cnt = raw.GetGauge()
val := cnt.GetValue()
c.Assert(val, gc.Equals, float64(1.0))
err = collection.Insert(bson.M{"test": true})
c.Assert(err, jc.ErrorIsNil)
u.Collect(ch)
// read the size
select {
case m = <-ch:
default:
c.Error("metric not provided by collector")
}
err = m.Write(&raw)
c.Assert(err, jc.ErrorIsNil)
cnt = raw.GetGauge()
valueTwo := cnt.GetValue()
c.Assert(2*valueOne, gc.Equals, valueTwo)
// read the count
select {
case m = <-ch:
default:
c.Error("metric not provided by collector")
}
err = m.Write(&raw)
c.Assert(err, jc.ErrorIsNil)
cnt = raw.GetGauge()
val = cnt.GetValue()
c.Assert(val, gc.Equals, float64(2.0))
}