Initial commit (by create-cloudflare CLI)

cool-dawn-3d3b/node_modules/better-sqlite3/lib/methods/backup.js

@@ -0,0 +1,67 @@
+'use strict';
+const fs = require('fs');
+const path = require('path');
+const { promisify } = require('util');
+const { cppdb } = require('../util');
+const fsAccess = promisify(fs.access);
+
+module.exports = async function backup(filename, options) {
+	if (options == null) options = {};
+
+	// Validate arguments
+	if (typeof filename !== 'string') throw new TypeError('Expected first argument to be a string');
+	if (typeof options !== 'object') throw new TypeError('Expected second argument to be an options object');
+
+	// Interpret options
+	filename = filename.trim();
+	const attachedName = 'attached' in options ? options.attached : 'main';
+	const handler = 'progress' in options ? options.progress : null;
+
+	// Validate interpreted options
+	if (!filename) throw new TypeError('Backup filename cannot be an empty string');
+	if (filename === ':memory:') throw new TypeError('Invalid backup filename ":memory:"');
+	if (typeof attachedName !== 'string') throw new TypeError('Expected the "attached" option to be a string');
+	if (!attachedName) throw new TypeError('The "attached" option cannot be an empty string');
+	if (handler != null && typeof handler !== 'function') throw new TypeError('Expected the "progress" option to be a function');
+
+	// Make sure the specified directory exists
+	await fsAccess(path.dirname(filename)).catch(() => {
+		throw new TypeError('Cannot save backup because the directory does not exist');
+	});
+
+	const isNewFile = await fsAccess(filename).then(() => false, () => true);
+	return runBackup(this[cppdb].backup(this, attachedName, filename, isNewFile), handler || null);
+};
+
+const runBackup = (backup, handler) => {
+	let rate = 0;
+	let useDefault = true;
+
+	return new Promise((resolve, reject) => {
+		setImmediate(function step() {
+			try {
+				const progress = backup.transfer(rate);
+				if (!progress.remainingPages) {
+					backup.close();
+					resolve(progress);
+					return;
+				}
+				if (useDefault) {
+					useDefault = false;
+					rate = 100;
+				}
+				if (handler) {
+					const ret = handler(progress);
+					if (ret !== undefined) {
+						if (typeof ret === 'number' && ret === ret) rate = Math.max(0, Math.min(0x7fffffff, Math.round(ret)));
+						else throw new TypeError('Expected progress callback to return a number or undefined');
+					}
+				}
+				setImmediate(step);
+			} catch (err) {
+				backup.close();
+				reject(err);
+			}
+		});
+	});
+};