@unirep/circuits/README.md

Client library for circuit related functions which are used in UniRep protocol.

# UniRep circuits package

Client library for circuit related functions which are used in UniRep protocol.

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---

## 💡 About UniRep
**UniRep** is a *private* and *non-repudiable* **data system**. Users can receive attestations from attesters, and voluntarily prove facts about their data without revealing the data itself. Moreover, users cannot refuse to receive attestations from an attester.

## 📘 Documentation

Read the [medium article](https://medium.com/privacy-scaling-explorations/unirep-a-private-and-non-repudiable-reputation-system-7fb5c6478549) to know more about the concept of UniRep protocol.
For more information, refer to the [documentation](https://developer.unirep.io/)

## 🛠 Install

### npm or yarn

Install the `@unirep/circuits` package with npm:

```bash
npm i @unirep/circuits
```

or yarn:

```bash
yarn add @unirep/circuits
```

## 📔 Usage

### Prover

**Use default nodejs prover**
```typescript
import { defaultProver } from '@unirep/circuits/provers/defaultProver'
```

**Use web prover**
```typescript
// default web prover from url: https://keys.unirep.io/${version}/.
import prover from '@unirep/circuits/provers/web'

// construct web prover from other url
import { WebProver } from '@unirep/circuits/provers/web'
const prover = new WebProver('https://YOUR/KEYS/URL')
```

**Generate proof and verify it with the above prover**
```typescript
import { Circuit } from '@unirep/circuits'

// See ./test/verifyEpochKey.test.ts for generating circuit inputs
const circuitInputs = {
    state_tree_elements: ...,
    state_tree_indices: ...,
    ...
}
const { proof, publicSignals } = await prover.genProofAndPublicSignals(
    Circuit.epochKey,
    circuitInputs
)

const isValid = await prover.verifyProof(
    Circuit.epochKey,
    publicSignals,
    proof
)
```

### Circom

Use the unirep [circom](https://docs.circom.io/) circuits like so:

```circom
pragma circom 2.1.0;

include "PATH/TO/node_modules/@unirep/circuits/circuits/epochKey.circom";

template DataProof(STATE_TREE_DEPTH, EPOCH_KEY_NONCE_PER_EPOCH, FIELD_COUNT) {
    signal input state_tree_indices[STATE_TREE_DEPTH];
    signal input state_tree_elements[STATE_TREE_DEPTH];
    signal input identity_secret;
    signal input data[FIELD_COUNT];
    signal input sig_data;
    signal input reveal_nonce;
    signal input attester_id;
    signal input epoch;
    signal input nonce;
    signal input chain_id;

    signal output epoch_key;
    signal output state_tree_root;
    signal output control;

    (epoch_key, state_tree_root, control) <== EpochKey(STATE_TREE_DEPTH, EPOCH_KEY_NONCE_PER_EPOCH, FIELD_COUNT)(
        state_tree_indices, 
        state_tree_elements, 
        identity_secret,
        reveal_nonce,
        attester_id,
        epoch,
        nonce,
        data,
        sig_data,
        chain_id
    );

    // add your customized circuits
    ...
}
```

### Proof helpers

Proof helpers can help users query the public signals in each proof.

**EpochKeyProof**

```ts
import { EpochKeyProof } from '@unirep/circuits'

const { proof, publicSignals } = await prover.genProofAndPublicSignals(
    Circuit.epochKey,
    circuitInputs
)
const data = new EpochKeyProof(publicSignals, proof)
const epk = data.epochKey
```

**SignupProof**

```ts
import { SignupProof } from '@unirep/circuits'

const { proof, publicSignals } = await prover.genProofAndPublicSignals(
    Circuit.signup,
    circuitInputs
)
const data = new SignupProof(publicSignals, proof)
const identityCommitment = data.identityCommitment
```

## 🙌🏻 Join our community
- Discord server: <a href="https://discord.gg/VzMMDJmYc5"><img src="https://img.shields.io/discord/931582072152281188?label=Discord&style=flat-square&logo=discord" /></a>
- Twitter account: <a href="https://twitter.com/UniRep_Protocol"><img src="https://img.shields.io/twitter/follow/UniRep_Protocol?style=flat-square&logo=twitter" /></a>
- Telegram group: <a href="https://t.me/unirep"><img src="https://img.shields.io/badge/telegram-@unirep-blue.svg?style=flat-square&logo=telegram" /></a>

## <img height="24" src="https://pse.dev/_next/static/media/header-logo.16312102.svg" /> Privacy & Scaling Explorations

This project is supported by [Privacy & Scaling Explorations](https://github.com/privacy-scaling-explorations) and the Ethereum Foundation.
See more projects on: https://pse.dev/.