Add Manager.UsersByIDs, a bulk user lookup for the rate visitor refresh

user/manager.go

@@ -26,6 +26,7 @@ const (
 	syncTopicPrefix                 = "st_"
 	syncTopicLength                 = 16
 	userIDPrefix                    = "u_"
+	usersByIDsChunk                 = 1000 // IDs per statement of UsersByIDs
 	userIDLength                    = 12
 	userAuthIntentionalSlowDownHash = "$2a$10$YFCQvqQDwIIwnJM1xkAYOeih0dg17UVGanaTStnrSzC8NCWxcLDwy" // Cost should match DefaultUserPasswordBcryptCost
 	userHardDeleteAfterDuration     = 7 * 24 * time.Hour
@@ -457,6 +458,29 @@ func (a *Manager) UserByID(id string) (*User, error) {
 	return a.readUser(rows)
 }
 
+// UsersByIDs returns the users with the given IDs, in chunks of usersByIDsChunk, skipping the IDs
+// that do not exist. Deleted users are returned as such; the caller decides what to do with them.
+// The IDs are passed as one JSON array, which both dialects unpack, so the statement is fixed.
+func (a *Manager) UsersByIDs(ids []string) ([]*User, error) {
+	users := make([]*User, 0, len(ids))
+	for chunk := range slices.Chunk(ids, usersByIDsChunk) {
+		param, err := json.Marshal(chunk)
+		if err != nil {
+			return nil, err
+		}
+		rows, err := a.db.Query(a.queries.selectUsersByIDs, string(param))
+		if err != nil {
+			return nil, err
+		}
+		chunkUsers, err := a.readUsers(rows)
+		if err != nil {
+			return nil, err
+		}
+		users = append(users, chunkUsers...)
+	}
+	return users, nil
+}
+
 // UserByEmailOrUsername resolves an identifier to a single user, trying it first as a primary
 // email address and then as a username. A verified, owned email takes precedence over a
 // freely-chosen username, so a look-alike username cannot shadow the email's real owner. Returns

user/manager_postgres.go

@@ -25,6 +25,12 @@ const (
 		LEFT JOIN tier t on t.id = u.tier_id
 		WHERE u.id = $1
 	`
+	postgresSelectUsersByIDsQuery = `
+		SELECT u.id, u.user_name, u.pass, u.role, u.prefs, u.sync_topic, u.provisioned, u.stripe_customer_id, u.stripe_subscription_id, u.stripe_subscription_status, u.stripe_subscription_interval, u.stripe_subscription_paid_until, u.stripe_subscription_cancel_at, u.deleted, t.id, t.code, t.name, t.messages_limit, t.messages_expiry_duration, t.emails_limit, t.calls_limit, t.reservations_limit, t.attachment_file_size_limit, t.attachment_total_size_limit, t.attachment_expiry_duration, t.attachment_bandwidth_limit, t.stripe_monthly_price_id, t.stripe_yearly_price_id
+		FROM "user" u
+		LEFT JOIN tier t on t.id = u.tier_id
+		WHERE u.id IN (SELECT jsonb_array_elements_text($1::jsonb))
+	`
 	postgresSelectUserByNameQuery = `
 		SELECT u.id, u.user_name, u.pass, u.role, u.prefs, u.sync_topic, u.provisioned, u.stripe_customer_id, u.stripe_subscription_id, u.stripe_subscription_status, u.stripe_subscription_interval, u.stripe_subscription_paid_until, u.stripe_subscription_cancel_at, u.deleted, t.id, t.code, t.name, t.messages_limit, t.messages_expiry_duration, t.emails_limit, t.calls_limit, t.reservations_limit, t.attachment_file_size_limit, t.attachment_total_size_limit, t.attachment_expiry_duration, t.attachment_bandwidth_limit, t.stripe_monthly_price_id, t.stripe_yearly_price_id
 		FROM "user" u
@@ -257,6 +263,7 @@ const (
 // NewPostgresManager creates a new Manager backed by a PostgreSQL database using an existing connection pool.
 var postgresQueries = queries{
 	selectUserByID:                 postgresSelectUserByIDQuery,
+	selectUsersByIDs:               postgresSelectUsersByIDsQuery,
 	selectUserByName:               postgresSelectUserByNameQuery,
 	selectUserByNameOrPrimaryEmail: postgresSelectUserByNameOrPrimaryEmailQuery,
 	selectUserByToken:              postgresSelectUserByTokenQuery,

user/manager_sqlite.go

@@ -31,6 +31,12 @@ const (
 		LEFT JOIN tier t on t.id = u.tier_id
 		WHERE u.id = ?
 	`
+	sqliteSelectUsersByIDsQuery = `
+		SELECT u.id, u.user, u.pass, u.role, u.prefs, u.sync_topic, u.provisioned, u.stripe_customer_id, u.stripe_subscription_id, u.stripe_subscription_status, u.stripe_subscription_interval, u.stripe_subscription_paid_until, u.stripe_subscription_cancel_at, deleted, t.id, t.code, t.name, t.messages_limit, t.messages_expiry_duration, t.emails_limit, t.calls_limit, t.reservations_limit, t.attachment_file_size_limit, t.attachment_total_size_limit, t.attachment_expiry_duration, t.attachment_bandwidth_limit, t.stripe_monthly_price_id, t.stripe_yearly_price_id
+		FROM user u
+		LEFT JOIN tier t on t.id = u.tier_id
+		WHERE u.id IN (SELECT value FROM json_each(?))
+	`
 	sqliteSelectUserByNameQuery = `
 		SELECT u.id, u.user, u.pass, u.role, u.prefs, u.sync_topic, u.provisioned, u.stripe_customer_id, u.stripe_subscription_id, u.stripe_subscription_status, u.stripe_subscription_interval, u.stripe_subscription_paid_until, u.stripe_subscription_cancel_at, deleted, t.id, t.code, t.name, t.messages_limit, t.messages_expiry_duration, t.emails_limit, t.calls_limit, t.reservations_limit, t.attachment_file_size_limit, t.attachment_total_size_limit, t.attachment_expiry_duration, t.attachment_bandwidth_limit, t.stripe_monthly_price_id, t.stripe_yearly_price_id
 		FROM user u
@@ -255,6 +261,7 @@ const (
 
 var sqliteQueries = queries{
 	selectUserByID:                 sqliteSelectUserByIDQuery,
+	selectUsersByIDs:               sqliteSelectUsersByIDsQuery,
 	selectUserByName:               sqliteSelectUserByNameQuery,
 	selectUserByNameOrPrimaryEmail: sqliteSelectUserByNameOrPrimaryEmailQuery,
 	selectUserByToken:              sqliteSelectUserByTokenQuery,

user/types.go

@@ -356,6 +356,7 @@ var (
 type queries struct {
 	// User queries
 	selectUserByID                 string
+	selectUsersByIDs               string
 	selectUserByName               string
 	selectUserByNameOrPrimaryEmail string
 	selectUserByToken              string