Add users count in leaderboard response with query parameter

docs/spec/paths/integrations@geo-points-svc@v1@public@balances.yaml

@@ -53,6 +53,13 @@ get:
     - $ref: '#/components/parameters/pageLimit'
     - $ref: '#/components/parameters/pageNumber'
     - $ref: '#/components/parameters/pageOrder'
+    - in: query
+      name: count
+      description: Count total number of users.
+      required: false
+      schema:
+        type: boolean
+        example: true
   responses:
     200:
       description: Success

internal/data/balances.go

@@ -44,6 +44,8 @@ type BalancesQ interface {
 	WithoutPassportEvent() ([]WithoutPassportEventBalance, error)
 	WithoutReferralEvent() ([]ReferredReferrer, error)
 
+	Count() (int64, error)
+
 	FilterByNullifier(...string) BalancesQ
 	FilterDisabled() BalancesQ
 	FilterByAnonymousID(id string) BalancesQ

internal/data/pg/balances.go

@@ -16,6 +16,7 @@ type balances struct {
 	db       *pgdb.DB
 	selector squirrel.SelectBuilder
 	updater  squirrel.UpdateBuilder
+	counter  squirrel.SelectBuilder
 	rank     squirrel.SelectBuilder
 }
 
@@ -24,6 +25,7 @@ func NewBalances(db *pgdb.DB) data.BalancesQ {
 		db:       db,
 		selector: squirrel.Select("*").From(balancesTable),
 		updater:  squirrel.Update(balancesTable),
+		counter:  squirrel.Select("COUNT(*) as count").From(balancesTable),
 		rank:     squirrel.Select("*, ROW_NUMBER() OVER (ORDER BY amount DESC, updated_at ASC) AS rank").From(balancesTable),
 	}
 }
@@ -55,6 +57,18 @@ func (q *balances) Update(fields map[string]any) error {
 	return nil
 }
 
+func (q *balances) Count() (int64, error) {
+	res := struct {
+		Count int64 `db:"count"`
+	}{}
+
+	if err := q.db.Get(&res, q.counter); err != nil {
+		return 0, fmt.Errorf("get balance: %w", err)
+	}
+
+	return res.Count, nil
+}
+
 // applyRankedPage is similar to the pgdb.OffsetParams.ApplyTo method,
 // but the sorting values are hardcoded because the fields must
 // be sorted in opposite directions
@@ -204,5 +218,6 @@ func (q *balances) applyCondition(cond squirrel.Sqlizer) data.BalancesQ {
 	q.selector = q.selector.Where(cond)
 	q.updater = q.updater.Where(cond)
 	q.rank = q.rank.Where(cond)
+	q.counter = q.counter.Where(cond)
 	return q
 }

internal/service/handlers/leaderboard.go

@@ -26,6 +26,18 @@ func Leaderboard(w http.ResponseWriter, r *http.Request) {
 
 	resp := newLeaderboardResponse(leaders)
 	resp.Links = req.GetLinks(r)
+	if req.Count {
+		leadersCount, err := BalancesQ(r).FilterDisabled().Count()
+		if err != nil {
+			Log(r).WithError(err).Error("Failed to count balances")
+			ape.RenderErr(w, problems.InternalError())
+			return
+		}
+
+		_ = resp.PutMeta(struct {
+			EventsCount int64 `json:"events_count"`
+		}{leadersCount})
+	}
 	ape.Render(w, resp)
 }
 

internal/service/requests/leaderboard.go

@@ -9,6 +9,7 @@ import (
 
 type Leaderboard struct {
 	page.OffsetParams
+	Count bool `url:"count"`
 }
 
 func NewLeaderboard(r *http.Request) (req Leaderboard, err error) {