The contents of this repo have been merged into ipfs/js-ipfs-unixfs.
Please open issues or submit PRs there.
JavaScript implementation of the exporter used by IPFS to handle Files
> npm install ipfs-unixfs-exporter
// import a file and export it again
const importer = require('ipfs-unixfs-importer')
const exporter = require('ipfs-unixfs-exporter')
const files = []
for await (const file of importer([{
path: '/foo/bar.txt',
content: Buffer.from(0, 1, 2, 3)
}], ipld)) {
files.push(file)
}
console.info(files[0].cid) // Qmbaz
const entry = await exporter(files[0].cid, ipld)
console.info(entry.cid) // Qmqux
console.info(entry.path) // Qmbaz/foo/bar.txt
console.info(entry.name) // bar.txt
console.info(entry.unixfs.fileSize()) // 4
// stream content from unixfs node
const bytes = []
for await (const buf of entry.content({
offset: 0, // optional offset
length: 4 // optional length
})) {
bytes.push(buf)
}
const content = Buffer.concat(bytes)
console.info(content) // 0, 1, 2, 3
const exporter = require('ipfs-unixfs-exporter')
Uses the given [js-ipld instance][] to fetch an IPFS node by it's CID.
Returns a Promise which resolves to an entry
.
Entries with a dag-pb
codec CID
return UnixFS V1 entries:
{
name: 'foo.txt',
path: 'Qmbar/foo.txt',
cid: CID, // see https://github.com/multiformats/js-cid
node: DAGNode, // see https://github.com/ipld/js-ipld-dag-pb
content: function, // returns an async iterator
unixfs: UnixFS // see https://github.com/ipfs/js-ipfs-unixfs
}
If the entry is a file, entry.content()
returns an async iterator that yields one or more buffers containing the file content:
if (entry.unixfs.type === 'file') {
for await (const chunk of entry.content()) {
// chunk is a Buffer
}
}
If the entry is a directory or hamt shard, entry.content()
returns further entry
objects:
if (entry.unixfs.type.includes('directory')) { // can be 'directory' or 'hamt-sharded-directory'
for await (const entry of dir.content()) {
console.info(entry.name)
}
}
Entries with a raw
codec CID
return raw entries:
{
name: 'foo.txt',
path: 'Qmbar/foo.txt',
cid: CID, // see https://github.com/multiformats/js-cid
node: Buffer, // see https://nodejs.org/api/buffer.html
content: function, // returns an async iterator
}
entry.content()
returns an async iterator that yields a buffer containing the node content:
for await (const chunk of entry.content()) {
// chunk is a Buffer
}
Unless you an options object containing offset
and length
keys as an argument to entry.content()
, chunk
will be equal to entry.node
.
Entries with a dag-cbor
codec CID
return JavaScript object entries:
{
name: 'foo.txt',
path: 'Qmbar/foo.txt',
cid: CID, // see https://github.com/multiformats/js-cid
node: Object, // see https://github.com/ipld/js-ipld-dag-cbor
}
There is no content
function for a CBOR
node.
When entry
is a file or a raw
node, offset
and/or length
arguments can be passed to entry.content()
to return slices of data:
const bufs = []
for await (const chunk of entry.content({
offset: 0,
length: 5
})) {
bufs.push(chunk)
}
// `data` contains the first 5 bytes of the file
const data = Buffer.concat(bufs)
If entry
is a directory or hamt shard, passing offset
and/or length
to entry.content()
will limit the number of files returned from the directory.
const entries = []
for await (const entry of dir.content({
offset: 0,
length: 5
})) {
entries.push(entry)
}
// `entries` contains the first 5 files/directories in the directory
exporter.path
will return an async iterator that yields entries for all segments in a path:
const entries = []
for await (const entry of exporter.path('Qmfoo/foo/bar/baz.txt', ipld)) {
entries.push(entry)
}
// entries contains 4x `entry` objects
exporter.recursive
will return an async iterator that yields all entries beneath a given CID or IPFS path, as well as the containing directory.
const entries = []
for await (const child of exporter.recursive('Qmfoo/foo/bar', ipld)) {
entries.push(entry)
}
// entries contains all children of the `Qmfoo/foo/bar` directory and it's children
Feel free to join in. All welcome. Open an issue!
This repository falls under the IPFS Code of Conduct.