https://github.com/ipfs/interface-datastore
datastore interface
https://github.com/ipfs/interface-datastore
Last synced: 9 months ago
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datastore interface
- Host: GitHub
- URL: https://github.com/ipfs/interface-datastore
- Owner: ipfs
- License: mit
- Archived: true
- Created: 2014-06-17T03:27:46.000Z (almost 12 years ago)
- Default Branch: master
- Last Pushed: 2021-09-09T11:19:13.000Z (almost 5 years ago)
- Last Synced: 2024-05-06T04:03:01.199Z (about 2 years ago)
- Language: JavaScript
- Homepage:
- Size: 1.59 MB
- Stars: 23
- Watchers: 26
- Forks: 20
- Open Issues: 8
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# ⛔️ DEPRECATED: This module has been merged into by the [ipfs-interfaces](https://github.com/ipfs/js-ipfs-interfaces) module
# interface-datastore
[](http://ipn.io)
[](http://ipfs.io/)
[](http://webchat.freenode.net/?channels=%23ipfs)
[](https://codecov.io/gh/ipfs/interface-datastore)
[](https://github.com/ipfs/interface-datastore/actions?query=branch%3Amaster+workflow%3Aci+)
> Implementation of the [datastore](https://github.com/ipfs/go-datastore) interface in JavaScript
## Lead Maintainer
[Alex Potsides](https://github.com/achingbrain)
## Table of Contents
- [Implementations](#implementations)
- [Adapter](#adapter)
- [Install](#install)
- [Usage](#usage)
- [Wrapping Stores](#wrapping-stores)
- [Test suite](#test-suite)
- [Aborting requests](#aborting-requests)
- [Concurrency](#concurrency)
- [Keys](#keys)
- [API](#api)
- [Contribute](#contribute)
- [License](#license)
## Implementations
- Backed Implementations
- Memory: [`src/memory`](src/memory.js)
- level: [`datastore-level`](https://github.com/ipfs/js-datastore-level) (supports any levelup compatible backend)
- File System: [`datstore-fs`](https://github.com/ipfs/js-datastore-fs)
- Wrapper Implementations
- Mount: [`datastore-core/src/mount`](https://github.com/ipfs/js-datastore-core/tree/master/src/mount.js)
- Keytransform: [`datstore-core/src/keytransform`](https://github.com/ipfs/js-datastore-core/tree/master/src/keytransform.js)
- Sharding: [`datastore-core/src/sharding`](https://github.com/ipfs/js-datastore-core/tree/master/src/sharding.js)
- Tiered: [`datstore-core/src/tiered`](https://github.com/ipfs/js-datastore-core/blob/master/src/tiered.js)
- Namespace: [`datastore-core/src/namespace`](https://github.com/ipfs/js-datastore-core/tree/master/src/namespace.js)
If you want the same functionality as [go-ds-flatfs](https://github.com/ipfs/go-ds-flatfs), use sharding with fs.
```js
const FsStore = require('datastore-fs')
const ShardingStore = require('datastore-core').ShardingDatastore
const NextToLast = require('datastore-core').shard.NextToLast
const fs = new FsStore('path/to/store')
// flatfs now works like go-flatfs
const flatfs = await ShardingStore.createOrOpen(fs, new NextToLast(2))
```
## Adapter
An adapter is made available to make implementing your own datastore easier:
```javascript
const { Adapter } = require('interface-datastore')
class MyDatastore extends Adapter {
constructor () {
super()
}
async put (key, val) {
// your implementation here
}
async get (key) {
// your implementation here
}
// etc...
}
```
See the [MemoryDatastore](./src/memory.js) for an example of how it is used.
## Install
```sh
$ npm install interface-datastore
```
## Usage
### Wrapping Stores
```js
const MemoryStore = require('interface-datastore').MemoryDatastore
const MountStore = require('datastore-core').MountDatastore
const Key = require('interface-datastore').Key
const store = new MountStore({ prefix: new Key('/a'), datastore: new MemoryStore() })
```
### Test suite
Available under [`src/tests.js`](src/tests.js)
```js
describe('mystore', () => {
require('interface-datastore/src/tests')({
async setup () {
return instanceOfMyStore
},
async teardown () {
// cleanup resources
}
})
})
```
### Aborting requests
Most API methods accept an [AbortSignal][] as part of an options object. Implementations may listen for an `abort` event emitted by this object, or test the `signal.aborted` property. When received implementations should tear down any long-lived requests or resources created.
### Concurrency
The streaming `(put|get|delete)Many` methods are intended to be used with modules such as [it-parallel-batch](https://www.npmjs.com/package/it-parallel-batch) to allow calling code to control levels of parallelisation. The batching method ensures results are returned in the correct order, but interface implementations should be thread safe.
```js
const batch = require('it-parallel-batch')
const source = [{
key: ..,
value: ..
}]
// put values into the datastore concurrently, max 10 at a time
for await (const { key, data } of batch(store.putMany(source), 10)) {
console.info(`Put ${key}`)
}
```
### Keys
To allow a better abstraction on how to address values, there is a `Key` class which is used as identifier. It's easy to create a key from a `Uint8Array` or a `string`.
```js
const a = new Key('a')
const b = new Key(new Uint8Array([0, 1, 2, 3]))
```
The key scheme is inspired by file systems and Google App Engine key model. Keys are meant to be unique across a system. They are typically hierarchical, incorporating more and more specific namespaces. Thus keys can be deemed 'children' or 'ancestors' of other keys:
- `new Key('/Comedy')`
- `new Key('/Comedy/MontyPython')`
Also, every namespace can be parameterized to embed relevant object information. For example, the Key `name` (most specific namespace) could include the object type:
- `new Key('/Comedy/MontyPython/Actor:JohnCleese')`
- `new Key('/Comedy/MontyPython/Sketch:CheeseShop')`
- `new Key('/Comedy/MontyPython/Sketch:CheeseShop/Character:Mousebender')`
## API
https://ipfs.github.io/interface-datastore/
## Contribute
PRs accepted.
Small note: If editing the Readme, please conform to the [standard-readme](https://github.com/RichardLitt/standard-readme) specification.
## License
MIT 2017 © IPFS
[Key]: #Keys
[Object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object
[Uint8Array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array
[AbortSignal]: https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal
[AsyncIterator]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/asyncIterator
[AsyncIterable]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols
[String]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String
[Array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
[Function]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function
[Number]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number
[Boolean]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean