Add prometheus

stats/prometheus_test.go

@@ -0,0 +1,97 @@
+package stats_test
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/9seconds/mtg/v2/events"
+	"github.com/9seconds/mtg/v2/mtglib"
+	"github.com/9seconds/mtg/v2/stats"
+	"github.com/stretchr/testify/suite"
+)
+
+type PrometheusTestSuite struct {
+	suite.Suite
+
+	httpListener net.Listener
+	factory      *stats.PrometheusFactory
+	prometheus   events.Observer
+}
+
+func (suite *PrometheusTestSuite) Get() (string, error) {
+	addr := fmt.Sprintf("http://%s/", suite.httpListener.Addr().String())
+
+	resp, err := http.Get(addr) // nolint: noctx
+	if err != nil {
+		return "", err // nolint: wrapcheck
+	}
+
+	defer resp.Body.Close()
+
+	data, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return "", err // nolint: wrapcheck
+	}
+
+	return string(data), nil
+}
+
+func (suite *PrometheusTestSuite) SetupTest() {
+	suite.httpListener, _ = net.Listen("tcp", "127.0.0.1:0")
+	suite.factory = stats.NewPrometheus("mtg", "/")
+	suite.prometheus = suite.factory.Make()
+
+	go suite.factory.Serve(suite.httpListener) // nolint: errcheck
+}
+
+func (suite *PrometheusTestSuite) TearDownTest() {
+	suite.prometheus.Shutdown()
+	suite.NoError(suite.factory.Close())
+	suite.httpListener.Close()
+}
+
+func (suite *PrometheusTestSuite) TestEventStartFinish() {
+	suite.prometheus.EventStart(mtglib.EventStart{
+		CreatedAt: time.Now(),
+		ConnID:    "connID",
+		RemoteIP:  net.ParseIP("10.0.0.10"),
+	})
+
+	time.Sleep(100 * time.Millisecond)
+
+	data, err := suite.Get()
+	suite.NoError(err)
+	suite.Contains(data, `mtg_active_connections{ip_type="ipv4"} 1`)
+
+	suite.prometheus.EventFinish(mtglib.EventFinish{
+		CreatedAt: time.Now(),
+		ConnID:    "connID",
+	})
+
+	time.Sleep(100 * time.Millisecond)
+
+	data, err = suite.Get()
+	suite.NoError(err)
+	suite.Contains(data, `mtg_active_connections{ip_type="ipv4"} 0`)
+}
+
+func (suite *PrometheusTestSuite) TestEventConcurrencyLimited() {
+	suite.prometheus.EventConcurrencyLimited(mtglib.EventConcurrencyLimited{
+		CreatedAt: time.Now(),
+	})
+
+	time.Sleep(100 * time.Millisecond)
+
+	data, err := suite.Get()
+	suite.NoError(err)
+	suite.Contains(data, `mtg_concurrency_limited 1`)
+}
+
+func TestPrometheus(t *testing.T) {
+	t.Parallel()
+	suite.Run(t, &PrometheusTestSuite{})
+}