FileSystemWrapper

Use the FileSystemWrapper class to perform operations on system files and folders when using platform APIs.

createReadStream

Creates a readable stream from the file you pass.

Parameter	Required	Type	Description
file	Yes	String	Path to the file
options	No	Object	Define additional options for your read stream
options.flags	No	String	A file system flag that describes how to handle the file, such as 'r' to read, 'a' to append, or 'w' to write. The default is 'w'.
options.encoding	No	String or null	File encoding. The default is 'utf8'.
options.fd	No	Number or FileHandler	A file descriptor to use for the stream instead of opening a new one. If specified, the path parameter is ignored.
options.mode	No	Number	Define the file's permissions with an octal. The default is 0o666, which is readable and writable for the owner, group, and others.
options.autoClose	No	Boolean	If set to false, the file descriptor won't automatically closed when the stream ends. The default value is true.
options.emitClose	No	Boolean	If set to false, the 'close' event will not be emitted once the file is closed.
options.start	No	Number	Byte offset to start reading the file.
options.end	No	Number	Byte offset to stop reading the file.
options.highWaterMark	No	Number	The maximum amount of data in bytes that can buffer at a time before the stream pauses, allowing the consumer to catch up. The default value is 64 * 1024.
options.fs	No	Object	null
options.signal	No	AbortSignal or null	Notifies observers when the stream aborts.

Returns

{Promise<ReadStream>} - Returns a promise with a read stream

Example

let file = {"folder/folder/example.txt"};
let options = {   mode: 0o777,   flag: 'r'};
const readableStream = await fs.createReadStream(file, options);

createWriteStream

Creates a writable stream for the file you pass.

Parameter	Required	Type	Description
file	Yes	String	Path to the file
options	No	Object	Define additional options for your write stream
options.flags	No	String	A file system flag that describes how to handle the file, such as 'r' to read, 'a' to append, or 'w' to write. The default is 'w'.
options.encoding	No	String or null	File encoding. The default is 'utf8'.
options.fd	No	Number or String	A file descriptor to use for the stream instead of opening a new one. If specified, the path parameter is ignored.
options.mode	No	Number	Define the file's permissions with an octal. The default is 0o666, which is readable and writable for the owner, group, and others.
options.autoClose	No	Boolean	If set to false, the file descriptor won't automatically be closed when the stream ends. The default value is true.
options.emitClose	No	Boolean	If set to false, the 'close' event will not be emitted once the file is closed.
options.start	No	Number	Byte offset to start reading the file.
options.fs	No	Object or null	Do we need this? (Specify the appropriate type if needed)
options.signal	No	AbortSignal or null	Notifies observers when the stream aborts.
options.highWaterMark	No	Number	The maximum amount of data in bytes that can buffer at a time before the stream pauses, allowing the consumer to catch up. The default value is 16384.
options.flush	No	Boolean	Set to 'true' to flush data after it is successfully written to the file. The default is 'false'.

Returns

{Promise<WriteStream>} - Returns a promise with a writable stream

Example

let file = "folder/folder/example.txt";
let options = {   mode: 0o777,   flag: 'w'};
const writableStream = await fs.createWriteStream(file, options);
writableStream.write('Hello, World!');writableStream.end();

existsSync

Synchronously checks if the file you pass exists in the File Service.

Parameter	Required	Type	Description
file	Yes	String	Path to the file

Returns

{Boolean} - Returns true if the file exists and false if it does not exist

Example

let file = "folder/folder/example.txt";
if (await fs.existsSync(file)) {  // Function to perform if the file exists} else {  // Function to perform if the file doesn't exist}

unlink

Asynchronously deletes the file you pass.

Parameter	Required	Type	Description
file	Yes	String	Path to the file

Example

let file = "folder/folder/example.txt";
await fs.unlink(file);

Returns

{Promise} - Returns a promise that resolves when the file is successfully deleted

unlinkSync

Synchronously deletes the file you pass.

Parameter	Required	Type	Description
file	Yes	String	Path to the file

Example

const file = "folder/folder/example.txt";
fs.unlinkSync(file);

Returns

No return value

mkdirsSync

Synchronously creates a directory and any required subdirectories.

Parameter	Required	Type	Description
dir	Yes	String	Directory path.
options	Yes	Integer or Object	Define the file's permissions with an octal. The default is 0o666, which is readable and writable for the owner, group, and others. Pass the octal directly or as an object with a 'mode' property and the octal as its value.

Example

const dir = "folder/folder/example";const mode = 0o2775;const options = {  mode: 0o2775};
fs.mkdirsSync(dir, mode);fs.mkdirsSync(dir, options);

Returns

No return value

readFileSync

Synchronously creates a readable stream from the file you pass.

Parameter	Required	Type	Description
file	Yes	String	Path to the file
options	No	FileOptions	Pass an options object. The default is 'undefined'.
options.encoding	No	String or null	File encoding. The default is 'utf8'.
options.flags	No	String	A file system flag that describes how to handle the file, such as 'r' to read, 'a' to append, or 'w' to write. The default is 'w'.
options.signal	No	AbortSignal	null

Example

const file = "folder/folder/example.txt";
const readableStream = await fs.readFileSync(file);

Returns

{ReadStream} - Returns a promise with a read stream

readdirSync

Synchronously reads the contents of a directory.

Parameter	Required	Type	Description
dir	Yes	String	Path to the directory.

Example

let dir = "root/folder/";
const readableDir = await fs.readdirSync(dir);

Returns

{ReadStream} - Returns a promise with a read stream

rmSync

Synchronously removes files and directories.

Parameter	Required	Type	Description
file	Yes	String	Path to the directory.
options	No	Options	Optionally pass an options object. The default value is undefined.
options.force	No	Boolean	Set to true to ignore exceptions if the path does not exist. The default value is false.
options.maxRetries	No	Number	Set the number of retries if an EBUSY, EMFILE, ENFILE, ENOTEMPTY, or EPERM error occurs. The retries occur with a linear backoff wait of the time defined in 'retryDelay'. The default value is 0. This option is ignored if 'recursive' is not true.
options.recursive	No	Boolean	Set to true to recursively remove the directory. On failure, the recursive operation retries. The default value is false.
options.retryDelay	No	Number	The time in milliseconds to wait between retries. This option is ignored if 'recursive' is false. The default value is 100.

Example

const file = "root/folder/";const options = {  maxRetries: 10,  recursive: true};
await fs.rmSync(file, options);

Returns

No return value

writeFileSync

Synchronously writes data to a file.

Parameter	Required	Type	Description
file	Yes	String	Path to the file
data	Yes	String or Buffer	Content to write to the file as a string or buffer
options	No	Options	Optionally pass an options object. The default value is undefined.
options.encoding	No	String or null	File encoding. The default is 'utf8'.
options.mode	No	Number	Define the file's permissions with an octal. The default is 0o666, which is readable and writable for the owner, group, and others.
options.flag	No	String	A file system flag that describes how to handle the file, such as 'r' to read, 'a' to append, or 'w' to write. The default is 'w'.
options.flush	No	Boolean	Set to 'true' to flush data after it is successfully written to the file. The default is 'false'.

Example

let file = "folder/folder/example.txt";let data = "String to write";
const writtenFile = await fs.writeFileSync(file, data);

Returns

No return value

rmdirSync

Synchronously removes a directory.

Parameter	Required	Type	Description
dir	Yes	String	Path to the directory.
options	No	Options	Optionally pass an options object. The default value is undefined.
options.maxRetries	No	Number	Set the number of retries if an EBUSY, EMFILE, ENFILE, ENOTEMPTY, or EPERM error occurs. The retries occur with a linear backoff wait of the time defined in 'retryDelay'. The default value is 0. This option is ignored if 'recursive' is not true.
options.recursive	No	Boolean	Set to true to recursively remove the directory. On failure, the recursive operation retries. The default value is false.
options.retryDelay	No	Number	The time in milliseconds to wait between retries. This option is ignored if 'recursive' is false. The default value is 100.

Example

let dir = "root-folder/folder";
await fs.rmdirSync(dir, options);
const options = {  maxRetries: 10,  recursive: true};

Returns

No return value