Wasm WNFS
This projects implements necessary JavaScript bindings for using the WebNative FileSystem (WNFS) Rust implementation in the browser.
WNFS is a versioned content-addressable distributed filesystem with private and public sub systems. The private filesystem is encrypted so that only users with the right keys can access its contents. It is designed to prevent inferring metadata like the structure of the file tree. The other part of the WNFS filesystem is a simpler public filesystem that is not encrypted and can be accessed by anyone with the right address.
WNFS also features collaborative editing of file trees, where multiple users can edit the same tree at the same time.
WNFS file trees can serialize and be deserialized from IPLD graphs with an extensible metadata section. This allows WNFS to be understood by other IPLD-based tools and systems.
Outline
Setting up the Project
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Install
wasm-pack
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Install dependencies
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Install playwright binaries
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Build project
Usage
WNFS does not have an opinion on where you want to persist your content or the file tree. Instead, the API expects any object that implements the async BlockStore
interface. This implementation also defers system-level operations to the user; requiring that operations like time and random number generation be passed in from the interface. This makes for a clean wasm interface that works everywhere.
Let's see an example of working with a public directory. Here we are going to use a custom-written memory-based blockstore.
import from "<custom>";
import from "wnfs";
const dir = ;
const store = ;
var = await dir.;
// Create a sample CIDv1.
const cid = Uint8Array.;
// Add a file to /pictures/cats.
var = await rootDir.;
// Create and add a file to /pictures/dogs directory.
var = await rootDir.;
// Delete /pictures/cats directory.
var = await rootDir.;
// List all files in /pictures directory.
var = await rootDir.;
console.log;
You may notice that we use the rootDir
s returned by each operation in subseqent operations. That is because WNFS internal state is immutable and every operation potentially returns a new root directory. This allows us to track and rollback changes when needed. It also makes collaborative editing easier to implement and reason about. There is a basic demo of the filesystem immutability here.
The private filesystem, on the other hand, is a bit more involved. Hash Array Mapped Trie (HAMT) is used as the intermediate format of private file tree before it is persisted to the blockstore. HAMT helps us hide the hierarchy of the file tree.
import from "<custom>";
import from "wnfs";
const initialHamt = ;
const rng = ;
const store = ;
const dir = ;
var = await root.;
// Add a file to /pictures/cats.
var = await rootDir.;
// Create and add a file to /pictures/dogs directory.
var = await rootDir.;
// Delete /pictures/cats directory.
var = await rootDir.;
// List all files in /pictures directory.
var = await rootDir.;
console.log;
Testing the Project
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Run tests
Publishing Package
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Build the project
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Publish from the
pkg
directory