CosmicClash/server/store/queue_sql.go

package store

import (
	"bytes"
	"context"
	"crypto/sha256"
	"database/sql"
	"encoding/json"
	"fmt"
	"time"

	"github.com/cosmic-clash/cosmic-clash/server/domain"
)

const (
	QueueIdempotencyScope     = "queue.create"
	QueueIdempotencyInsertSQL = `INSERT INTO idempotency_keys (scope, idempotency_key, payload_digest, result)
VALUES ($1, $2, $3, $4)
ON CONFLICT (scope, idempotency_key) DO NOTHING`
	QueueIdempotencySelectSQL = `SELECT payload_digest, result
FROM idempotency_keys
WHERE scope = $1 AND idempotency_key = $2
FOR UPDATE`
	QueueTicketSelectSQL = `SELECT ticket_id, player_id, playlist, state, client_build,
    protocol_version, enqueued_at, expires_at, revision
FROM queue_tickets
WHERE ticket_id = $1 AND player_id = $2`
)

func CreateQueueTicket(ctx context.Context, db *sql.DB, ticketID, playerID, idempotencyKey string, spec domain.QueueSpec, now time.Time) (domain.QueueTicket, error) {
	if db == nil || ticketID == "" || playerID == "" || len(idempotencyKey) < 16 || len(idempotencyKey) > 128 || (spec.Playlist != domain.Casual && spec.Playlist != domain.Ranked) || spec.ClientBuild == "" || len(spec.ClientBuild) > 128 || spec.ProtocolVersion < 1 || now.IsZero() {
		return domain.QueueTicket{}, fmt.Errorf("invalid queue transaction arguments")
	}
	digest := sha256.Sum256([]byte(fmt.Sprintf("%s|%s|%s|%s|%d", ticketID, playerID, spec.Playlist, spec.ClientBuild, spec.ProtocolVersion)))
	var ticket domain.QueueTicket
	err := RunSerializable(ctx, db, DefaultSerializableAttempts, func(ctx context.Context, tx *sql.Tx) error {
		candidate := domain.Candidate{TicketID: ticketID, PlayerID: playerID, Playlist: spec.Playlist, ClientBuild: spec.ClientBuild, ProtocolVersion: spec.ProtocolVersion, EnqueuedAt: now}
		ticket = domain.QueueTicket{TicketID: ticketID, PlayerID: playerID, Candidate: candidate, Playlist: spec.Playlist, State: domain.Queued, EnqueuedAt: now, ExpiresAt: now.Add(domain.QueueExpiryWindow)}
		stored, err := json.Marshal(queueTicketRecordFromDomain(ticket))
		if err != nil {
			return err
		}
		result, err := tx.ExecContext(ctx, QueueIdempotencyInsertSQL, QueueIdempotencyScope, idempotencyKey, digest[:], stored)
		if err != nil {
			return err
		}
		inserted, err := result.RowsAffected()
		if err != nil {
			return err
		}
		if inserted == 0 {
			var priorDigest, priorResult []byte
			if err := tx.QueryRowContext(ctx, QueueIdempotencySelectSQL, QueueIdempotencyScope, idempotencyKey).Scan(&priorDigest, &priorResult); err != nil {
				return err
			}
			if !bytes.Equal(priorDigest, digest[:]) {
				return fmt.Errorf("queue create idempotency conflict")
			}
			var prior queueTicketRecord
			if err := json.Unmarshal(priorResult, &prior); err != nil {
				return fmt.Errorf("invalid stored queue result: %w", err)
			}
			ticket = queueTicketRecordToDomain(prior)
			return nil
		}
		_, err = tx.ExecContext(ctx, QueueTicketInsertSQL, ticketID, playerID, string(spec.Playlist), string(domain.Queued), spec.ClientBuild, spec.ProtocolVersion, now, ticket.ExpiresAt)
		return err
	})
	return ticket, err
}

type queueTicketRecord struct {
	TicketID        string    `json:"ticket_id"`
	PlayerID        string    `json:"player_id"`
	Playlist        string    `json:"playlist"`
	State           string    `json:"state"`
	ClientBuild     string    `json:"client_build"`
	ProtocolVersion int       `json:"protocol_version"`
	EnqueuedAt      time.Time `json:"enqueued_at"`
	ExpiresAt       time.Time `json:"expires_at"`
	Revision        uint64    `json:"revision"`
}

func GetQueueTicket(ctx context.Context, db *sql.DB, playerID, ticketID string) (domain.QueueTicket, error) {
	if db == nil || playerID == "" || ticketID == "" {
		return domain.QueueTicket{}, fmt.Errorf("invalid queue recovery arguments")
	}
	var record queueTicketRecord
	if err := db.QueryRowContext(ctx, QueueTicketSelectSQL, ticketID, playerID).Scan(&record.TicketID, &record.PlayerID, &record.Playlist, &record.State, &record.ClientBuild, &record.ProtocolVersion, &record.EnqueuedAt, &record.ExpiresAt, &record.Revision); err != nil {
		return domain.QueueTicket{}, err
	}
	return queueTicketRecordToDomain(record), nil
}

func queueTicketRecordFromDomain(ticket domain.QueueTicket) queueTicketRecord {
	return queueTicketRecord{ticket.TicketID, ticket.PlayerID, string(ticket.Playlist), string(ticket.State), ticket.Candidate.ClientBuild, ticket.Candidate.ProtocolVersion, ticket.EnqueuedAt, ticket.ExpiresAt, ticket.Revision}
}
func queueTicketRecordToDomain(record queueTicketRecord) domain.QueueTicket {
	candidate := domain.Candidate{TicketID: record.TicketID, PlayerID: record.PlayerID, Playlist: domain.Playlist(record.Playlist), ClientBuild: record.ClientBuild, ProtocolVersion: record.ProtocolVersion, EnqueuedAt: record.EnqueuedAt}
	return domain.QueueTicket{TicketID: record.TicketID, PlayerID: record.PlayerID, Candidate: candidate, Playlist: domain.Playlist(record.Playlist), State: domain.State(record.State), Revision: record.Revision, EnqueuedAt: record.EnqueuedAt, ExpiresAt: record.ExpiresAt}
}