A blob store for Hypercore
npm install hyperblobsA simple blob store for Hypercore.
Each blob is identified by its unique bounds within the Hypercore, e.g. { byteOffset: 0, blockOffset: 0, blockLength: 5, byteLength: 327680 }, which makes them easy to save and retrieve:
``js`
const blobs = new Hyperblobs(core)
// ID is { byteOffset: 0, blockOffset: 0, blockLength: 1, byteLength: 11 }
const id = await blobs.put(Buffer.from('hello world', 'utf-8'))
await blobs.get(id) // Buffer.from('hello world', 'utf-8')
You can also get from start/end bounds within a single blob:
`js`
const blobs = new Hyperblobs(core)
// ID is { byteOffset: 0, blockOffset: 0, blockLength: 1, byteLength: 11 }
const id = await blobs.put(Buffer.from('hello world', 'utf-8'))
await blobs.get(id, { start: 1, length: 2 }) // Buffer.from('el', 'utf-8')
If the blob is large, there's a Streams interface (createReadStream and createWriteStream) too.
npm i hyperblobs
API
js
const Hyperblobs = require('hyperblobs')
`####
Create a new blob store wrapping a single Hypercore.Options can include:
js
{
blockSize: 64KB // The block size that will be used when storing large blobs.
}
`####
Store a new blob. If the blob is large, it will be chunked according to (default 64KB).Options can include:
`js
{
blockSize: 64KB, // The block size that will be used when storing large blobs.
start: 0, // Relative offset to start within the blob
end: blob.length - 1, // End offset within the blob (inclusive)
length: blob.length, // Number of bytes to read.
core // A custom core to write (overrides the default core)
}
`####
Return a complete blob as a .id is the value returned by putOptions can include:
js
{
core, // A custom core to read from (overrides the default core)
wait: true, // Wait for block to be downloaded
timeout: 0 // Wait at max some milliseconds (0 means no timeout)
}
`####
Remove a blob from the core. are the same as Hypercore.clear method.####
const stream = blobs.createReadStream(id, opts)
Create a Readable stream that will yield the blob.Options match the
get options.####
const stream = blobs.createWriteStream(opts)
Create a Writable stream that will save a blob.The corresponding ID will be set on the stream at