github.com/juju/juju@v0.0.0-20240430160146-1752b71fcf00/worker/dbaccessor/metrics_test.go (about)

     1  // Copyright 2023 Canonical Ltd.
     2  // Licensed under the AGPLv3, see LICENCE file for details.
     3  
     4  package dbaccessor
     5  
     6  import (
     7  	"bytes"
     8  	time "time"
     9  
    10  	jc "github.com/juju/testing/checkers"
    11  	"github.com/prometheus/client_golang/prometheus/testutil"
    12  	gc "gopkg.in/check.v1"
    13  
    14  	"github.com/juju/juju/testing"
    15  )
    16  
    17  type metricsSuite struct {
    18  	baseSuite
    19  }
    20  
    21  var _ = gc.Suite(&metricsSuite{})
    22  
    23  func (s *metricsSuite) TestMetricsAreCollected(c *gc.C) {
    24  	collector := NewMetricsCollector()
    25  
    26  	done := make(chan struct{})
    27  	go func() {
    28  		defer close(done)
    29  		collector.DBDuration.WithLabelValues("foo", "success").Observe(0.1)
    30  		collector.DBRequests.WithLabelValues("foo").Inc()
    31  		collector.TxnRequests.WithLabelValues("foo").Inc()
    32  	}()
    33  
    34  	select {
    35  	case <-done:
    36  	case <-time.After(testing.ShortWait):
    37  		c.Fatalf("timed out waiting for metrics to be collected")
    38  	}
    39  
    40  	expected := bytes.NewBuffer([]byte(`
    41  # HELP juju_db_duration_seconds Total time spent in db requests.
    42  # TYPE juju_db_duration_seconds histogram
    43  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.005"} 0
    44  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.01"} 0
    45  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.025"} 0
    46  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.05"} 0
    47  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.1"} 1
    48  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.25"} 1
    49  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="0.5"} 1
    50  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="1"} 1
    51  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="2.5"} 1
    52  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="5"} 1
    53  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="10"} 1
    54  juju_db_duration_seconds_bucket{namespace="foo",result="success",le="+Inf"} 1
    55  juju_db_duration_seconds_sum{namespace="foo",result="success"} 0.1
    56  juju_db_duration_seconds_count{namespace="foo",result="success"} 1
    57  # HELP juju_db_requests_total Number of active db requests.
    58  # TYPE juju_db_requests_total gauge
    59  juju_db_requests_total{namespace="foo"} 1
    60  # HELP juju_db_txn_requests_total Total number of txn requests including retries.
    61  # TYPE juju_db_txn_requests_total counter
    62  juju_db_txn_requests_total{namespace="foo"} 1
    63  		`[1:]))
    64  
    65  	err := testutil.CollectAndCompare(
    66  		collector, expected,
    67  		"juju_db_requests_total",
    68  		"juju_db_duration_seconds",
    69  		"juju_db_txn_requests_total",
    70  	)
    71  	if !c.Check(err, jc.ErrorIsNil) {
    72  		c.Logf("\nerror:\n%v", err)
    73  	}
    74  }