refactor: Start implementation of public API

internal/persisters/sqlite.go

@@ -0,0 +1,44 @@
+package persisters
+
+import (
+	"database/sql"
+	"os"
+	"path/filepath"
+
+	_ "github.com/mattn/go-sqlite3"
+	migrate "github.com/rubenv/sql-migrate"
+)
+
+type SQLite struct {
+	DBPath     string
+	Migrations migrate.MigrationSource
+
+	db *sql.DB
+}
+
+func (s *SQLite) Open() error {
+	// Create leading directories for database
+	leadingDir, _ := filepath.Split(s.DBPath)
+	if err := os.MkdirAll(leadingDir, os.ModePerm); err != nil {
+		return err
+	}
+
+	// Open the DB
+	db, err := sql.Open("sqlite3", s.DBPath)
+	if err != nil {
+		return err
+	}
+
+	// Configure the db
+	db.SetMaxOpenConns(1) // Prevent "database locked" errors
+	s.db = db
+
+	// Run migrations if set
+	if s.Migrations != nil {
+		if _, err := migrate.Exec(s.db, "sqlite3", s.Migrations, migrate.Up); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}