microcms_sdk_generator
Version:
A type-safe MicroCMS SDK Generator
164 lines (163 loc) • 5.89 kB
JavaScript
// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
import * as dntShim from "../../../../_dnt.shims.js";
/**
* Test whether or not the given path exists by checking with the file system. Please consider to check if the path is readable and either a file or a directory by providing additional `options`:
*
* ```ts
* import { exists } from "https://deno.land/std@$STD_VERSION/fs/mod.ts";
* const isReadableDir = await exists("./foo", {
* isReadable: true,
* isDirectory: true
* });
* const isReadableFile = await exists("./bar", {
* isReadable: true,
* isFile: true
* });
* ```
*
* Note: Do not use this function if performing a check before another operation on that file. Doing so creates a race condition. Instead, perform the actual file operation directly.
*
* Bad:
* ```ts
* import { exists } from "https://deno.land/std@$STD_VERSION/fs/mod.ts";
*
* if (await exists("./foo")) {
* await Deno.remove("./foo");
* }
* ```
*
* Good:
* ```ts
* // Notice no use of exists
* try {
* await Deno.remove("./foo", { recursive: true });
* } catch (error) {
* if (!(error instanceof Deno.errors.NotFound)) {
* throw error;
* }
* // Do nothing...
* }
* ```
* @see https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use
*/
export async function exists(path, options) {
try {
const stat = await dntShim.Deno.stat(path);
if (options &&
(options.isReadable || options.isDirectory || options.isFile)) {
if (options.isDirectory && options.isFile) {
throw new TypeError("ExistsOptions.options.isDirectory and ExistsOptions.options.isFile must not be true together.");
}
if ((options.isDirectory && !stat.isDirectory) ||
(options.isFile && !stat.isFile)) {
return false;
}
if (options.isReadable) {
if (stat.mode == null) {
return true; // Exclusive on Non-POSIX systems
}
if (dntShim.Deno.uid() == stat.uid) {
return (stat.mode & 0o400) == 0o400; // User is owner and can read?
}
else if (dntShim.Deno.gid() == stat.gid) {
return (stat.mode & 0o040) == 0o040; // User group is owner and can read?
}
return (stat.mode & 0o004) == 0o004; // Others can read?
}
}
return true;
}
catch (error) {
if (error instanceof dntShim.Deno.errors.NotFound) {
return false;
}
if (error instanceof dntShim.Deno.errors.PermissionDenied) {
if ((await dntShim.Deno.permissions.query({ name: "read", path })).state ===
"granted") {
// --allow-read not missing
return !options?.isReadable; // PermissionDenied was raised by file system, so the item exists, but can't be read
}
}
throw error;
}
}
/**
* Test whether or not the given path exists by checking with the file system. Please consider to check if the path is readable and either a file or a directory by providing additional `options`:
*
* ```ts
* import { existsSync } from "https://deno.land/std@$STD_VERSION/fs/mod.ts";
* const isReadableDir = existsSync("./foo", {
* isReadable: true,
* isDirectory: true
* });
* const isReadableFile = existsSync("./bar", {
* isReadable: true,
* isFile: true
* });
* ```
*
* Note: do not use this function if performing a check before another operation on that file. Doing so creates a race condition. Instead, perform the actual file operation directly.
*
* Bad:
* ```ts
* import { existsSync } from "https://deno.land/std@$STD_VERSION/fs/mod.ts";
*
* if (existsSync("./foo")) {
* Deno.removeSync("./foo");
* }
* ```
*
* Good:
* ```ts
* // Notice no use of existsSync
* try {
* Deno.removeSync("./foo", { recursive: true });
* } catch (error) {
* if (!(error instanceof Deno.errors.NotFound)) {
* throw error;
* }
* // Do nothing...
* }
* ```
* @see https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use
*/
export function existsSync(path, options) {
try {
const stat = dntShim.Deno.statSync(path);
if (options &&
(options.isReadable || options.isDirectory || options.isFile)) {
if (options.isDirectory && options.isFile) {
throw new TypeError("ExistsOptions.options.isDirectory and ExistsOptions.options.isFile must not be true together.");
}
if ((options.isDirectory && !stat.isDirectory) ||
(options.isFile && !stat.isFile)) {
return false;
}
if (options.isReadable) {
if (stat.mode == null) {
return true; // Exclusive on Non-POSIX systems
}
if (dntShim.Deno.uid() == stat.uid) {
return (stat.mode & 0o400) == 0o400; // User is owner and can read?
}
else if (dntShim.Deno.gid() == stat.gid) {
return (stat.mode & 0o040) == 0o040; // User group is owner and can read?
}
return (stat.mode & 0o004) == 0o004; // Others can read?
}
}
return true;
}
catch (error) {
if (error instanceof dntShim.Deno.errors.NotFound) {
return false;
}
if (error instanceof dntShim.Deno.errors.PermissionDenied) {
if (dntShim.Deno.permissions.querySync({ name: "read", path }).state === "granted") {
// --allow-read not missing
return !options?.isReadable; // PermissionDenied was raised by file system, so the item exists, but can't be read
}
}
throw error;
}
}