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Module

std/fs/ensure_file.ts

The Deno Standard Library
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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { dirname } from "../path/dirname.ts";import { ensureDir, ensureDirSync } from "./ensure_dir.ts";import { getFileInfoType } from "./_get_file_info_type.ts";import { toPathString } from "./_to_path_string.ts";
/** * Asynchronously ensures that the file exists. If the file that is requested to * be created is in directories that do not exist, these directories are created. * If the file already exists, it is not modified. * * Requires the `--allow-read` and `--allow-write` flag. * * @param filePath The path of the file to ensure, as a string or URL. * @returns A void promise that resolves once the file exists. * * @example * ```ts * import { ensureFile } from "https://deno.land/std@$STD_VERSION/fs/ensure_file.ts"; * * await ensureFile("./folder/targetFile.dat"); * ``` */export async function ensureFile(filePath: string | URL): Promise<void> { try { // if file exists const stat = await Deno.lstat(filePath); if (!stat.isFile) { throw new Error( `Ensure path exists, expected 'file', got '${getFileInfoType(stat)}'`, ); } } catch (err) { // if file not exists if (err instanceof Deno.errors.NotFound) { // ensure dir exists await ensureDir(dirname(toPathString(filePath))); // create file await Deno.writeFile(filePath, new Uint8Array()); return; }
throw err; }}
/** * Synchronously ensures that the file exists. If the file that is requested to * be created is in directories that do not exist, these directories are created. * If the file already exists, it is not modified. * * Requires the `--allow-read` and `--allow-write` flag. * * @param filePath The path of the file to ensure, as a string or URL. * @returns A void value that returns once the file exists. * * @example * ```ts * import { ensureFileSync } from "https://deno.land/std@$STD_VERSION/fs/ensure_file.ts"; * * ensureFileSync("./folder/targetFile.dat"); * ``` */export function ensureFileSync(filePath: string | URL): void { try { // if file exists const stat = Deno.lstatSync(filePath); if (!stat.isFile) { throw new Error( `Ensure path exists, expected 'file', got '${getFileInfoType(stat)}'`, ); } } catch (err) { // if file not exists if (err instanceof Deno.errors.NotFound) { // ensure dir exists ensureDirSync(dirname(toPathString(filePath))); // create file Deno.writeFileSync(filePath, new Uint8Array()); return; } throw err; }}