refactor sqlite queue

internal/sqlc/sqlite_queue.go

@@ -0,0 +1,93 @@
+package sqlc
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"sync"
+)
+
+const writeBufferSize = 100
+
+type SqlcGeneric func(*Queries, context.Context, any) error
+
+type WriteTx struct {
+	ErrChan chan error
+	Query   SqlcGeneric
+	Args    interface{}
+}
+
+type Queue struct {
+	Queries    *Queries
+	Db         *sql.DB
+	WriteQueue chan WriteTx
+	wg         sync.WaitGroup
+	ctx        context.Context
+	cancel     context.CancelFunc
+}
+
+func NewQueue(sqlDb *sql.DB, ctx context.Context) (*Queue, error) {
+	ctx, cancel := context.WithCancel(context.Background())
+	sqldb := &Queue{
+		Queries:    New(sqlDb),
+		Db:         sqlDb,
+		WriteQueue: make(chan WriteTx, writeBufferSize),
+		ctx:        ctx,
+		cancel:     cancel,
+	}
+
+	return sqldb, nil
+}
+
+func (d *Queue) Start() {
+	d.wg.Add(1)
+	defer d.wg.Done()
+	go func() {
+		for {
+			select {
+			case <-d.ctx.Done():
+				return
+			case writeTx := <-d.WriteQueue:
+				err := writeTx.Query(d.Queries, d.ctx, writeTx.Args)
+				writeTx.ErrChan <- err
+			}
+		}
+	}()
+}
+
+func (d *Queue) Stop() error {
+	d.cancel()
+	d.wg.Wait()
+	close(d.WriteQueue)
+	return d.Db.Close()
+}
+
+func (d *Queue) EnqueueWriteTx(queryFunc SqlcGeneric, args any) error {
+	select {
+	case <-d.ctx.Done():
+		return errors.New("database is shutting down")
+	default:
+	}
+
+	errChan := make(chan error, 1)
+	writeTx := WriteTx{
+		Query:   queryFunc,
+		Args:    args,
+		ErrChan: errChan,
+	}
+	d.WriteQueue <- writeTx
+	return <-errChan
+}
+
+func OpenSqliteDb(dbPath string) (*sql.DB, error) {
+	sqliteDb, err := sql.Open("sqlite3", dbPath)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open database: %w", err)
+	}
+
+	if err := sqliteDb.Ping(); err != nil {
+		return nil, fmt.Errorf("failed to connect to database: %w", err)
+	}
+	return sqliteDb, nil
+}