Daily Active User Metrics (#3735)

* agent: add StatsReporter

* Stabilize protoc

coderd/metricscache/metricscache_test.go

@@ -0,0 +1,185 @@
+package metricscache_test
+
+import (
+	"context"
+	"reflect"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/require"
+
+	"cdr.dev/slog/sloggers/slogtest"
+	"github.com/coder/coder/coderd/database"
+	"github.com/coder/coder/coderd/database/databasefake"
+	"github.com/coder/coder/coderd/metricscache"
+	"github.com/coder/coder/codersdk"
+	"github.com/coder/coder/testutil"
+)
+
+func date(year, month, day int) time.Time {
+	return time.Date(year, time.Month(month), day, 0, 0, 0, 0, time.UTC)
+}
+
+func TestCache(t *testing.T) {
+	t.Parallel()
+
+	var (
+		zebra = uuid.New()
+		tiger = uuid.New()
+	)
+
+	type args struct {
+		rows []database.InsertAgentStatParams
+	}
+	tests := []struct {
+		name string
+		args args
+		want []codersdk.DAUEntry
+	}{
+		{"empty", args{}, nil},
+		{"one hole", args{
+			rows: []database.InsertAgentStatParams{
+				{
+					CreatedAt: date(2022, 8, 27),
+					UserID:    zebra,
+				},
+				{
+					CreatedAt: date(2022, 8, 30),
+					UserID:    zebra,
+				},
+			},
+		}, []codersdk.DAUEntry{
+			{
+				Date:   date(2022, 8, 27),
+				Amount: 1,
+			},
+			{
+				Date:   date(2022, 8, 28),
+				Amount: 0,
+			},
+			{
+				Date:   date(2022, 8, 29),
+				Amount: 0,
+			},
+			{
+				Date:   date(2022, 8, 30),
+				Amount: 1,
+			},
+		}},
+		{"no holes", args{
+			rows: []database.InsertAgentStatParams{
+				{
+					CreatedAt: date(2022, 8, 27),
+					UserID:    zebra,
+				},
+				{
+					CreatedAt: date(2022, 8, 28),
+					UserID:    zebra,
+				},
+				{
+					CreatedAt: date(2022, 8, 29),
+					UserID:    zebra,
+				},
+			},
+		}, []codersdk.DAUEntry{
+			{
+				Date:   date(2022, 8, 27),
+				Amount: 1,
+			},
+			{
+				Date:   date(2022, 8, 28),
+				Amount: 1,
+			},
+			{
+				Date:   date(2022, 8, 29),
+				Amount: 1,
+			},
+		}},
+		{"holes", args{
+			rows: []database.InsertAgentStatParams{
+				{
+					CreatedAt: date(2022, 1, 1),
+					UserID:    zebra,
+				},
+				{
+					CreatedAt: date(2022, 1, 1),
+					UserID:    tiger,
+				},
+				{
+					CreatedAt: date(2022, 1, 4),
+					UserID:    zebra,
+				},
+				{
+					CreatedAt: date(2022, 1, 7),
+					UserID:    zebra,
+				},
+				{
+					CreatedAt: date(2022, 1, 7),
+					UserID:    tiger,
+				},
+			},
+		}, []codersdk.DAUEntry{
+			{
+				Date:   date(2022, 1, 1),
+				Amount: 2,
+			},
+			{
+				Date:   date(2022, 1, 2),
+				Amount: 0,
+			},
+			{
+				Date:   date(2022, 1, 3),
+				Amount: 0,
+			},
+			{
+				Date:   date(2022, 1, 4),
+				Amount: 1,
+			},
+			{
+				Date:   date(2022, 1, 5),
+				Amount: 0,
+			},
+			{
+				Date:   date(2022, 1, 6),
+				Amount: 0,
+			},
+			{
+				Date:   date(2022, 1, 7),
+				Amount: 2,
+			},
+		}},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			var (
+				db    = databasefake.New()
+				cache = metricscache.New(db, slogtest.Make(t, nil), time.Millisecond*100)
+			)
+
+			defer cache.Close()
+
+			templateID := uuid.New()
+			db.InsertTemplate(context.Background(), database.InsertTemplateParams{
+				ID: templateID,
+			})
+
+			for _, row := range tt.args.rows {
+				row.TemplateID = templateID
+				db.InsertAgentStat(context.Background(), row)
+			}
+
+			var got codersdk.TemplateDAUsResponse
+
+			require.Eventuallyf(t, func() bool {
+				got = cache.TemplateDAUs(templateID)
+				return reflect.DeepEqual(got.Entries, tt.want)
+			}, testutil.WaitShort, testutil.IntervalFast,
+				"GetDAUs() = %v, want %v", got, tt.want,
+			)
+		})
+	}
+}