mantaray-js
v1.0.3
Published
Mantaray data structure in JS
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Description
With this package you can manipulate and interpret mantaray data via MantarayNode
and MantarayFork
abstractions.
Exported Functions and Classes
You can import the followings directly from mantaray-js
:
- MantarayNode # class abstracting and manipulating Mantaray Node data
- MantarayFork # class abstracting and manipulating Mantaray Fork data
- checkForSeparator # checks for separator character in the node and its descendants prefixes
- initManifestNode # initialize a manifest node
- loadAllNodes # loads all mantaray nodes recursively from the storage
- equalNodes # checks whether the two given Mantaray Nodes objects are equal in the in-memory abstraction level
- Utils # all used utility functions in the library. Mostly operating on
Uint8Array
objects. - types* # not callable, referring all types exported and reachable from the index
Basic usage
Construct Mantaray
import { initManifestNode, Utils } from 'mantaray-js'
const node = initManifestNode()
const address1 = Utils.gen32Bytes() // instead of `gen32Bytes` some 32 bytes identifier that later could be retrieved from the storage
const address2 = Utils.gen32Bytes()
const address3 = Utils.gen32Bytes()
const address4 = Utils.gen32Bytes()
const address5 = Utils.gen32Bytes()
const path1 = new TextEncoder().encode('path1/valami/elso')
const path2 = new TextEncoder().encode('path1/valami/masodik')
const path3 = new TextEncoder().encode('path1/valami/masodik.ext')
const path4 = new TextEncoder().encode('path1/valami')
const path5 = new TextEncoder().encode('path2')
node.addFork(path1, address1)
node.addFork(path2, address2, { vmi: 'elso' }) // here 'vmi' is a key of metadata and 'elso' is its value
node.addFork(path3, address3)
node.addFork(path4, address4, { vmi: 'negy' })
node.addFork(path5, address5)
node.removePath(path3)
// (...)
Mantaray Storage Operations
import { MantarayNode } from 'mantaray-js'
const node = new MantarayNode()
// here `reference` parameter is a `Reference` type which can be a 32 or 64 bytes Uint8Array
// and `loadFunction` is a [loadFunction: async (address: Reference): Promise<Uint8Array>] typed function
// that returns the serialised raw data of a MantarayNode of the given reference
await node.load(loadFunction, reference)
// Manipulate `node` object then save it again
// (...)
// save into the storage with a storage handler [saveFuncion: async (data: Uint8Array): Promise<Reference>]
const reference = await node.save(saveFunction)
node binary format
The following describes the format of a node binary format.
┌────────────────────────────────┐
│ obfuscationKey <32 byte> │
├────────────────────────────────┤
│ hash("mantaray:0.1") <31 byte> │
├────────────────────────────────┤
│ refBytesSize <1 byte> │
├────────────────────────────────┤
│ entry <32/64 byte> │
├────────────────────────────────┤
│ forksIndexBytes <32 byte> │
├────────────────────────────────┤
│ ┌────────────────────────────┐ │
│ │ Fork 1 │ │
│ ├────────────────────────────┤ │
│ │ ... │ │
│ ├────────────────────────────┤ │
│ │ Fork N │ │
│ └────────────────────────────┘ │
└────────────────────────────────┘
Fork
┌───────────────────┬───────────────────────┬──────────────────┐
│ nodeType <1 byte> │ prefixLength <1 byte> │ prefix <30 byte> │
├───────────────────┴───────────────────────┴──────────────────┤
│ reference <32/64 bytes> │
│ │
└──────────────────────────────────────────────────────────────┘
Fork with metadata
┌───────────────────┬───────────────────────┬──────────────────┐
│ nodeType <1 byte> │ prefixLength <1 byte> │ prefix <30 byte> │
├───────────────────┴───────────────────────┴──────────────────┤
│ reference <32/64 bytes> │
│ │
├─────────────────────────────┬────────────────────────────────┤
│ metadataBytesSize <2 bytes> │ metadataBytes <varlen> │
├─────────────────────────────┘ │
│ │
└──────────────────────────────────────────────────────────────┘
Testing
The testing needs running Bee client node for integration testing.
You can set BEE_POSTAGE
environment variable with a valid Postage batch or the test will create one for you.
The default value of the Bee Debug API endpoint is http://localhost:1635
.
If your address diverges from that, please, set BEE_DEBUG_API_URL
system environment variable with yours.
To run test execute
npm run test
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See what "Maintainer" means here.