Devlink-core NPM

devlink-core

What is it?

Devlink is a simple tool, that can create symbolic link in your system from source to destination file. Usage is really simple and there are more ways how to use this api. It's implemented as functional, promise, throwable and with callbacks. Devlink keeps original file, so you can always revert link operation by unlink operation, that's return previous file.

functional API

function `link(on: string, to: string): Either<LinkError, LinkResult>`

This is a functional alternative of link method. This method take 2 parameters and return Either monad, that contains LinkError if method fail or LinkResults if everything is done correctly. This method create link from on file to to file.

Parameters:

on - path to file when we need to create link, file must exist
to - path to file where link will be pointing, file must exist

Returns:

Either<LinkError, LinkResult>

Example:

import { functional } from "devlink-core";

const { link } = functional;
const result = link("/data/sources/source.txt", "/data/links/link.txt");

function `unlink(on: string): Either<UnlinkError, UnlinkResult>`

This is a functional alternative of unlink method. This method take 1 parameter and return Either monad, that contains UnlinkError if method fail or UnlinkResult if everything is done correctly. This method remove link created by link method on on file.

Parameters:

on - path to file where link is created, file must exist

Returns:

Either<UnlinkError, UnlinkResult>

Example:

import { functional } from "devlink-core";

const { unlink } = functional;
const result = unlink("/data/sources/source.txt");

function `linked(on: string): E.Either<never, LinkedResult>`

This is a functional alternative of linked method. This method take 1 parameter and return Either monad, that contains LinkedResult if everything is done correctly. This method never fail. This method is used to check if on file exists link, that is created by link function.

Parameters:

on - path to file where we want to check if link is created

Returns:

Either<never, LinkedResult>

Example:

import { functional } from "devlink-core";

const { linked } = functional;
const result = linked("/data/sources/source.txt");

promise API

function `link(on: string, to: string): Promise<LinkResult>`

This is a promise alternative of link method. This method take 2 parameters and return promise, that return LinkResults if everything is done correctly and catch LinkError if fails. This method create link from on file to to file.

Parameters:

on - path to file when we need to create link, file must exist
to - path to file where link will be pointing, file must exist

Returns:

Promise<LinkResult>

Catch:

LinkError

Example:

import { promise } from "devlink-core";

const { link } = promise;
link("/data/sources/source.txt", "/data/links/link.txt")
	.then((result) => {})
	.catch((err) => {});

function `unlink(on: string): Promise<UnlinkResult>`

This is a promise alternative of unlink method. This method take 1 parameter and return promise, that return UnlinkResult if everything is done correctly and catch LinkError if fails. This method remove link created by link method on on file.

Parameters:

on - path to file where link is created, file must exist

Returns:

Promise<UnlinkResult>

Catch:

LinkError

Example:

import { promise } from "devlink-core";

const { unlink } = promise;
unlink("/data/sources/source.txt")
	.then((result) => {})
	.catch((err) => {});

function `linked(on: string): Promise<LinkedResult | null>`

This is a promise alternative of linked method. This method take 1 parameter and return promise, that contains LinkedResult if everything is done correctly. This method never fail. This method is used to check if on file exists link, that is created by link function.

Parameters:

on - path to file where we want to check if link is created

Returns:

Promise<LinkedResult | null>

Example:

import { promise } from "devlink-core";

const { linked } = promise;
linked("/data/sources/source.txt").then((result) => {});

throwable API

function `link(on: string, to: string): LinkResult`

This is a throwable alternative of link method. This method take 2 parameters and return result LinkResults if everything is done correctly and throw LinkThrow if fails. This method create link from on file to to file.

Parameters:

on - path to file when we need to create link, file must exist
to - path to file where link will be pointing, file must exist

Returns:

LinkResult

Throw:

LinkThrow

Example:

import { throwable } from "devlink-core";

const { link } = throwable;
try {
	const results = link("/data/sources/source.txt", "/data/links/link.txt");
} catch (err) {
	// handle error
}

function `unlink(on: string): Promise<UnlinkResult>`

This is a throwable alternative of unlink method. This method take 1 parameter and return UnlinkResult if everything is done correctly and throw LinkThrow if fails. This method remove link created by link method on on file.

Parameters:

on - path to file where link is created, file must exist

Returns:

UnlinkResult

Throw:

LinkThrow

Example:

import { throwable } from "devlink-core";

const { unlink } = throwable;
try {
	const results = unlink("/data/sources/source.txt");
} catch (err) {
	// handle error
}

function `linked(on: string): Promise<LinkedResult | null>`

This is a throwable alternative of linked method. This method take 1 parameter and return LinkedResult if everything is done correctly or null if there is some error. This method never fail. This method is used to check if on file exists link, that is created by link function.

Parameters:

on - path to file where we want to check if link is created

Returns:

LinkedResult | null

Example:

import { throwable } from "devlink-core";

const { linked } = throwable;
const result = linked("/data/sources/source.txt");

callback API

function `link(on: string, to: string, onDone: (err: LinkThrow | null, res: LinkResult | null) => void): void`

This is a callback alternative of link method. This method take 3 parameters and return void. Last parameter is callback function with error LinkThrow and result LinkResults. If something failed result parameter is null, is everything is ok, err parameter is null. This method create link from on file to to file.

Parameters:

on - path to file when we need to create link, file must exist
to - path to file where link will be pointing, file must exist
onDone - callback function with err and result

Example:

import { callback } from "devlink-core";

const { link } = callback;
link("/data/sources/source.txt", "/data/links/link.txt", (err, result) => {
	if (result) {
		// handle result
	}
	if (err) {
		// handle error
	}
});

function `unlink(on: string, onDone: (err: LinkThrow | null, res: UnlinkResult | null) => void): void`

This is a callback alternative of unlink method. This method take 2 parameters and return void. Last parameter is callback function with error LinkThrow and result UnlinkResult. If something failed result parameter is null, is everything is ok, err parameter is null. This method remove link created by link method on on file.

Parameters:

on - path to file where link is created, file must exist
onDone - callback function with err and result

Example:

import { callback } from "devlink-core";

const { unlink } = callback;
unlink("/data/sources/source.txt", (err, result) => {
	if (result) {
		// handle result
	}
	if (err) {
		// handle error
	}
});

function `linked(on: string): Promise<LinkedResult | null>`

This is a callback alternative of linked method. This method take 2 parameters and return void. Last parameter is callback function with result UnlinkResult or null. If something failed result parameter is null. This method is used to check if on file exists link, that is created by link function.

Parameters:

on - path to file where we want to check if link is created
onDone - callback function with err and result

Example:

import { callback } from "devlink-core";

const { linked } = callback;
linked("/data/sources/source.txt", (result) => {
	if (result) {
		// handle result
	} else {
		// handle error
	}
});