Secure File Host

Filesystem host toolkit for Browser-Desktop datasource connections

About

This library provides an event emitter and an Express application for use with the Buttercup Desktop application - It's designed to provide an interface for Browser extension users to connect on for reading and writing vault files on the local system.

Some users may not want to have their vault files synchronised via a cloud storage service, and this tool is designed to allow them to read files on their PC without the need for connecting to external services.

Installation

Simply run npm install @buttercup/secure-file-host --save to install.

This library is only designed to work with Node JS.

Usage

Create and run an express server:

const { startFileHost } = require("@buttercup/secure-file-host");

const host = startFileHost(9998);
// host.key is the encryption key

In this example, the browser can connect to the file host service on port 9998.

For repeated use, you may want to provide your own key:

startFileHost(9998, "some-encryption-key");

You can stop the service when closing the application:

const host = startFileHost(9998);

// later
host.stop();

If a user wants to cancel the handskahe procedure, make sure to call the host.cancel() method to prevent a deadlock.

More details available in the API documentation

Debugging

You can run a debug server that uses the host by running npm start. You can stop the server by pressing Ctrl+C.

Emitted events

The returned host object contains an emitter property, which is an event emitter instance. It emits the following events:

Event Slug	Schedule	Description
codeReady	On client connect	A client has connected and is awaiting a code to be presented so that the user can enter it in the other application's interface.
connectionAvailabilityChanged	When the status of the host in terms of it accepting new connections changes	Called with an object like { available: true } when the availability of the host changes. It will be fired with { available: false } when someone is trying to connect, and it will stay unavailable until it is either connected or cancelled. If a wrong code is attempted it will stay unavailable for a further 15 seconds.
connected	When connection and handshake procedures have been completed	When the entire handshake procedure has been completed successfully the connected event is fired with no arguments.
connectionFailed	When an incorrect code is entered	Fired when a client tries to use an incorrect code.