Initial vibeproxy implementation

Self-contained HTTP/HTTPS/TCP/UDP reverse proxy manager written in Go,
with SQLite storage, a Bootstrap 5 admin UI (Go templates, no JS
framework), and a REST API under /api/v1.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QTXFrNP1imCW7jtfL5SZrw

internal/database/database.go

@@ -0,0 +1,100 @@
+// Package database owns the SQLite connection, pragmas, and migrations.
+package database
+
+import (
+	"database/sql"
+	"embed"
+	"fmt"
+	"io/fs"
+	"sort"
+	"strings"
+
+	_ "modernc.org/sqlite"
+)
+
+//go:embed migrations/*.sql
+var migrationsFS embed.FS
+
+// Open opens (creating if needed) the SQLite database at path, applies
+// pragmas suited for a long-running server (WAL, foreign keys, busy
+// timeout), and runs any pending migrations.
+func Open(path string) (*sql.DB, error) {
+	dsn := fmt.Sprintf("file:%s?_pragma=busy_timeout(5000)", path)
+	db, err := sql.Open("sqlite", dsn)
+	if err != nil {
+		return nil, err
+	}
+	// SQLite only tolerates a single writer; keep the pool modest so
+	// writers serialize instead of colliding on SQLITE_BUSY.
+	db.SetMaxOpenConns(8)
+
+	pragmas := []string{
+		"PRAGMA journal_mode=WAL",
+		"PRAGMA synchronous=NORMAL",
+		"PRAGMA foreign_keys=ON",
+		"PRAGMA busy_timeout=5000",
+	}
+	for _, p := range pragmas {
+		if _, err := db.Exec(p); err != nil {
+			db.Close()
+			return nil, fmt.Errorf("pragma %q: %w", p, err)
+		}
+	}
+
+	if err := migrate(db); err != nil {
+		db.Close()
+		return nil, fmt.Errorf("migrate: %w", err)
+	}
+	return db, nil
+}
+
+func migrate(db *sql.DB) error {
+	if _, err := db.Exec(`CREATE TABLE IF NOT EXISTS schema_migrations (
+		version TEXT PRIMARY KEY,
+		applied_at TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now'))
+	)`); err != nil {
+		return err
+	}
+
+	entries, err := fs.ReadDir(migrationsFS, "migrations")
+	if err != nil {
+		return err
+	}
+	var names []string
+	for _, e := range entries {
+		if !e.IsDir() && strings.HasSuffix(e.Name(), ".sql") {
+			names = append(names, e.Name())
+		}
+	}
+	sort.Strings(names)
+
+	for _, name := range names {
+		var applied int
+		if err := db.QueryRow(`SELECT COUNT(*) FROM schema_migrations WHERE version = ?`, name).Scan(&applied); err != nil {
+			return err
+		}
+		if applied > 0 {
+			continue
+		}
+		content, err := migrationsFS.ReadFile("migrations/" + name)
+		if err != nil {
+			return err
+		}
+		tx, err := db.Begin()
+		if err != nil {
+			return err
+		}
+		if _, err := tx.Exec(string(content)); err != nil {
+			tx.Rollback()
+			return fmt.Errorf("applying %s: %w", name, err)
+		}
+		if _, err := tx.Exec(`INSERT INTO schema_migrations (version) VALUES (?)`, name); err != nil {
+			tx.Rollback()
+			return err
+		}
+		if err := tx.Commit(); err != nil {
+			return err
+		}
+	}
+	return nil
+}