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11.1.4 • Public • Published


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JavaScript implementation of IPFS' unixfs (a Unix FileSystem representation on top of a MerkleDAG)


This module contains the protobuf definition of the UnixFS data structure found at the root of all UnixFS DAGs.

The UnixFS spec can be found in the ipfs/specs repository

Example - Create a file composed of several blocks

const data = new UnixFS({ type: 'file' })
data.addBlockSize(256) // add the size of each block
// ...

Example - Create a directory that contains several files

Creating a directory that contains several files is achieve by creating a unixfs element that identifies a MerkleDAG node as a directory. The links of that MerkleDAG node are the files that are contained in this directory.

const data = new UnixFS({ type: 'directory' })

Example - Create an unixfs Data element

const data = new UnixFS([options])

options is an optional object argument that might include the following keys:

  • type (string, default file): The type of UnixFS entry. Can be:
    • raw
    • directory
    • file
    • metadata
    • symlink
    • hamt-sharded-directory
  • data (Uint8Array): The optional data field for this node
  • blockSizes (Array, default: []): If this is a file node that is made up of multiple blocks, blockSizes is a list numbers that represent the size of the file chunks stored in each child node. It is used to calculate the total file size.
  • mode (Number, default 0644 for files, 0755 for directories/hamt-sharded-directories) file mode
  • mtime (Date, { secs, nsecs }, { Seconds, FractionalNanoseconds }, [ secs, nsecs ]): The modification time of this node

Example - Add and remove a block size to the block size list

data.addBlockSize(<size in bytes>)

Example - Get total fileSize

data.fileSize() // => size in bytes

Example - Marshal and unmarshal

const marshaled = data.marshal()
const unmarshaled = Unixfs.unmarshal(marshaled)

Example - Is this UnixFS entry a directory?

const dir = new Data({ type: 'directory' })
dir.isDirectory() // true

const file = new Data({ type: 'file' })
file.isDirectory() // false

Example - Has an mtime been set?

If no modification time has been set, no mtime property will be present on the Data instance:

const file = new Data({ type: 'file' })
file.mtime // undefined

Object.prototype.hasOwnProperty.call(file, 'mtime') // false

const dir = new Data({ type: 'dir', mtime: new Date() })
dir.mtime // { secs: Number, nsecs: Number }


$ npm i ipfs-unixfs

Browser <script> tag

Loading this module through a script tag will make it's exports available as IpfsUnixfs in the global namespace.

<script src="https://unpkg.com/ipfs-unixfs/dist/index.min.js"></script>

API Docs


Licensed under either of


Contributions welcome! Please check out the issues.

Also see our contributing document for more information on how we work, and about contributing in general.

Please be aware that all interactions related to this repo are subject to the IPFS Code of Conduct.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.



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