# @ethereumjs/ethash

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| [Ethash](https://github.com/ethereum/wiki/wiki/Ethash) implementation in TypeScript. |
| --- |

Note: this `README` reflects the state of the library from `v1.0.0` onwards. See `README` from the [standalone repository](https://github.com/ethereumjs/ethashjs) for an introduction on the last preceeding release.

# INSTALL

`npm install @ethereumjs/ethash`

# USAGE

```typescript
import Ethash from '@ethereumjs/ethash'
import { Block } from '@ethereumjs/block'
const level = require('level-mem')

const cacheDB = level()

const ethash = new Ethash(cacheDB)
const validblockRlp =
  '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'

const validBlock = Block.fromRLPSerializedBlock(Buffer.from(validblockRlp, 'hex'))

const result = await ethash.verifyPOW(validBlock)
console.log(result) // => true
```

# BROWSER

Yep, you can [browserify](http://browserify.org/) it.

# API

- [`new Ethash([cacheDB])`](#newethashcachedb)
- [`ethash.verifyPOW(block)`](#ethashverifypowblock)
- [`ethash.mkcache(cacheSize, seed)`](#ethashmkcachecachesize-seed)
- [`ethash.run(val, nonce, fullsize)`](#ethashrunval-nonce-fullsize)

### `new Ethash([cacheDB])`

Creates a new instance of `Ethash`.

**Parameters**

- `cacheDB` - an instance of a levelup db which is used to store the cache(s)

### `ethash.verifyPOW(block)`

Verifies the POW on a block and its uncles.

Returns a promise that resolves to a boolean.

**Parameters**

- `block` - the [@ethereumjs/block](https://github.com/ethereumjs/ethereumjs-vm/tree/master/packages/block) to verify

### `ethash.mkcache(cacheSize, seed)`

Creates a cache. NOTE: this is automatically done for in - [`ethash.verifyPOW(block)`](#ethashverifypowblock) so you do not need to use this function if you are just validating blocks

**Parameters**

- `cachSize` - the size of the cach
- `seed` - the seed as a `Buffer`

### `ethash.run(val, nonce, fullsize)`

Runs ethash on a give val/nonce pair. NOTE: you need to run [`ethash.mkcache(cacheSize, seed)`](#ethashverifypowcachesize-seed) first before using this function.

**Parameters**

- `val` - value to run ethash on e.g. the header hash
- `nonce` - the nonce used for this hash attempt
- `fullsize` - the fullsize of the cache.

**Returns**

An `Object` containing:

- `hash` - the hash of the value
- `mix` - the mis result

# TESTS

`npm run test`

# LICENSE

[MPL-2.0](https://www.mozilla.org/MPL/2.0/)

[discord-badge]: https://img.shields.io/static/v1?logo=discord&label=discord&message=Join&color=blue
[discord-link]: https://discord.gg/TNwARpR
[ethash-npm-badge]: https://img.shields.io/npm/v/@ethereumjs/ethash.svg
[ethash-npm-link]: https://www.npmjs.org/package/@ethereumjs/ethash
[ethash-issues-badge]: https://img.shields.io/github/issues/ethereumjs/ethereumjs-vm/package:%20ethash?label=issues
[ethash-issues-link]: https://github.com/ethereumjs/ethereumjs-vm/issues?q=is%3Aopen+is%3Aissue+label%3A"package%3A+ethash"
[ethash-actions-badge]: https://github.com/ethereumjs/ethereumjs-vm/workflows/Ethash/badge.svg
[ethash-actions-link]: https://github.com/ethereumjs/ethereumjs-vm/actions?query=workflow%3A%22Ethash%22
[ethash-coverage-badge]: https://codecov.io/gh/ethereumjs/ethereumjs-vm/branch/master/graph/badge.svg?flag=ethash
[ethash-coverage-link]: https://codecov.io/gh/ethereumjs/ethereumjs-vm/tree/master/packages/ethash