Arbor Protocol

The Arbor Protocol, or more simply called Arbor, is a schelling game where the objective is to publicly co-create songs worthy of purchase by NFT collectors.

LIVE DEMO: https://arbor.audio

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Contracts

This application is run on the Polygon Mainnet network. All contracts are deployed at the following addresses:

Contract	Address
ArborAudioCollections	0xf6c55e9fAeeaa214f4B23c92e0C88953D19e3dD0
StemQueue	0x222bF026aCd1Aece8DB92172F161D63AaC369Bba
Verifier20	0x410c16A302d7672a9bEEBE6aF0E4c37122244E13
PoseidonT3	0x5616971539C1d6aCb632A997436f66eA35f66CBC
IncrementalMerkleTree	0x55D5452Ba831D0aa0Dd0fc8D304D3bcAE8220385

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Zero-Knowledge SNARKs

Arbor uses zero knowledge technologies to incorporate anonymous voting on stems that are within a Project's Stem Queue. It accomplishes this by using a series of zkSNARKs and relying on some of the packages to incorporate these into the dApp.

Library	Use Case
@semaphore-protocol/group	To create the on-chain Semaphore voting group for a given Project
@zk-kit/identity	To create the anonymous identity for the voter
@zk-kit/protocols	To generate the off-chain proof and witness to submit to the on-chain verifier that a voter is a member of the Project's voting group

Anonymous Voting Workflow

The workflow for the zkSNARK use with Semaphore groups within the dApp are as follows:

1. A user creates a new project. A new Semaphore group is created on chain and tied to a unique identifier for the project.
2. A user uploads a stem onto a project. The stem is put into the Stem Queue.
3. With stems available in the queue, a user can register to be a voter for this project. A message is signed and an identity commitment is created from the signature. The commitment is then submitted to the on-chain group and stored in the Merkle tree for the given group that is tied to the given Project.
4. Only registered users can cast votes on available stems within the Stem Queue. When a user votes on a stem, the signal is the stem's unique identifier stored in MongoDB. A Merkle proof is generated from the voter's identity along with all the other identities stored from other users within the voting group. A witness is generated from this proof and used to create a full proof with the WASM and verification key SNARK-based files initially created from the trusted setup. This full proof is then submitted along with the signal to the StemQueue.sol contract. The contract function then verifies the proof. If all is okay, the function will succeed and the vote is stored on-chain, anonymously.
5. With stems having at least one vote, a collaborator of the Project can then approve the stem to be added on for the next slot. This will remove the stem from the Stem Queue.
6. The user who uploaded the approved stem will now become a collaborator on the Project and will gain approval permissions.
7. Collaborators can register and vote within the Stem Queue as well, allowing them to remain anonymous and contribute to voting.

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Local Development - Getting Started

First, clone this repository to your local machine:

git clone https://github.com/arbor-protocol/ui.git

There is some local setup that needs to happen to fully run this client application locally.

Dependencies:

• npm or yarn
• Node.js
• MongoDB

1. Install dependencies

You can download the latest version of Node.js here. You can check that you are running NPM and Node with the following commands:

node -v
# v16.14.0

npm -v
# 8.3.1

Install the client dependencies with the following command:

yarn install
# or
npm install

2. Environment Variables

Next, set up local environment variables by copying over the values from .env to a .env.local file. Run the following command:

# Unix
cp .env .env.local
# windows
xcopy .env .env.local

NOTE: Please reach out to the core team for a set of values to fill in your local env file.

3. Run the Application

Finally, you can run the development server using the following command:

yarn dev
# or
npm run dev

Open http://localhost:3000 with your browser to see the result.

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Setting Up A Local Database (MongoDB)

This client application is using the built-in Next.js API routes that read and write to a local Mongo database. Here are our recommended steps for getting up and running with a local MongoDB environment:

1. Install a MongoDB Host

We recommend using MongoDB Community Edition, because it is free and has all the necessary features.

This will set up a host to run in the background on the machine. You can then connect to it via a number of methods when it is up.

• For Mac users, you can follow the steps listed here.
• For Windows users, you can follow the steps listed here.

2. Install a MongoDB Client

There are many ways to interact with a MongoDB host. My recommendation is to use a GUI, as it makes for viewing the data easily, and MongoDB Compass is free and easy to use. Install it using the documentation here.

3. Create a Connection

Once MongoDB Compass is installed and you have a MongoDB host running in the background, you can now connect the client to the host and set up this new connection. Open up Compass and click "New Connection" in the top left of the GUI, or in the menubar. Paste in the local connection string; it should look similar to this on Mac:

mongodb://localhost:27017/?readPreference=primary&appname=MongoDB%20Compass&ssl=false

4. Create a Database and Link It

Create a new database for Arbor. Title it arbor-protocol or whatever suits your fancy. It may prompt you to add a collection to it as well. Please add a users collection.

The important bit is to update your local environment variables in the client app. Update the following in .env.local to your new connection string:

MONGODB_URI=mongodb://localhost/arbor-protocol

This will now allow the client app to work with the local MongoDB instance, and you can now interact with it through Compass as a GUI.

NOTE: You can always shut down the background mongo daemon that's running after using it. For Mac and Homebrew users, you can check that it's running with brew services list, and then you can shut it down with brew services stop mongodb-community. For Windows users, it would be net stop MongoDB, which is the default service name from the installer.

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Issues

We encourage the open-source atmosphere. If you find any bugs or issues with this repository, don't hesitate to file an issue for it. We will work to continually engage with these issues and encourage you to contribute.