backend

Setting up MoneyVigil Backend

The steps below will help you fill in the right details in the settings file. To begin with, copy the conf.example.json to conf.json

You will need a Linux or Mac OS environment to run this backend.

Install all required Python modules

pip install -r requirements.txt

Interacting with the Ethereum components

EthVigil Beta Developer Account

https://github.com/blockvigil/ethvigil-cli

Follow the instructions contained in the link above to install ev-cli, the CLI tool to interact with EthVigil APIs and also complete your signup for a developer account on EthVigil.

EthVigil Python SDK

https://github.com/blockvigil/ethvigil-python-sdk

With the fresh EthVigil Beta signup and CLI installed, next up is installation of the EthVigil Python SDK.

Run the following command

pip install git+https://github.com/blockvigil/ethvigil-python-sdk.git

Open up ~/.ethvigil/settings.json and copy over the following fields to conf.json

"PRIVATEKEY" to️ "privatekey"

"REST_API_ENDPOINT" : "https://beta.ethvigil.com/api"

"ETHVIGIL_USER_ADDRESS" (same field in both files)

"ETHVIGIL_API_KEY" (same)

Deploy contracts/Main.sol

Use EthVigil to deploy the Solidity Smart Contract, Main.sol.

• Deploy contract from Web UI
• Deploy contract from CLI

Fill this deployed contract address in the following field in conf.json

{"contractAddress": "0xContractAddress"}

Ethereum Name Service (ENS)

Deploy contracts/MoneyVigilENSHandler.sol

Register a top level domain on ENS and record the corresponding namehash and string in the conf.json

{
  "ENSManagerContract": "0xContractAddress",
  "topLevelENSDomain": {
      "name": "topleveldomain.eth",
      "nameHash": "0xNameHash"
  },

From the Entity dashboard screen, ensure the displayed contract address is assigned the ownership on the top level ENS domain. For the purpose of this demo, it gives it the right to create further subdomains corresponding to new entity registrations on MoneyVigil.

You hace to call setOwner(nameHash, ENSManagerContractAddress) on the contract 0x00000000000C2E074eC69A0dFb2997BA6C7d2e1e (ENSRegistryWithFallback)

Dai and Compound Dai contracts

Fill up the following fields in conf.json . You can find these contracts on the Goerli testnet.

{
    "DaiContract": "0xdc31ee1784292379fbb2964b3b9c4124d8f89c60",
    "cDaiContract": "0x822397d9a55d0fefd20F5c4bCaB33C5F65bd28Eb"
}

Set up webhook integrations on them by pointing them to the address webhook_listener.py is listening on.

Set up the public URL endpoint as a webhook integration for the smart contracts.

• From Web UI
• From CLI

http://<URL_ENDPOINT>/dai for the Dai contract webhook integration http://<URL_ENDPOINT>/cdai for the Compound Dai contract webhook integration

Databases and cache

Redis Configuration

You have to fill the appropriate host IP, port numbers and database number into the settings file section as follows (leave the CLUSTER_MODE mode set to False):

"REDIS": {  
    "HOST": "127.0.0.1",
    "PORT": 6380,
    "DB": 0,
    "PASSWORD": null,
    "CLUSTER_MODE": false
},

Neo4j Graph Database

Enter the right credentials in

"NEO4J": {
      "URL": "bolt://neo4j:neo4j@localhost:7687",
      "USERNAME": "neo4j",
      "PASSWORD": "neo4j"
    },

MySQL Relational Database

Enter the appropriate MySQL credentials in the following section in conf.json

"MYSQL": {
      "HOST": "192.168.99.100",
      "USER": "root",
      "PASSWORD": "",
      "DB": "hackmoney"
    },

Alembic + SQLAlchemy for separation of concerns between data models and migration operations.

Initialize Graph and Relational DB with a few users

chmod +x db_reset_instructions.sh
./db_reset_instructions.sh

Amazon SES credentials

The backend code currently uses SES credentials to send out emails. Find the following section in the settings file and fill in the neccessary details:

"SES_CREDENTIALS": {  
    "from": "",  
    "region": "",  
    "accessKeyId": "",  
    "secretAccessKey": "",  
    "accountId": 0  
  },

Main backend - Flask server

chmod +x run_flask.sh
./run_flask.sh

You can visit http://localhost:5000 and take a look at the REST API exposed for this project.

Off-chain data and logic integrator

python webhook_listener.py

Receipts

Run a Sia node

We can attach receipts and cheques with filed expenses to act as proofs. These are stored on the Sia decentralized storage platform.

We are not using the Skynet APIs. Instead we have been running our own nodes to connect to the Sia chain and speaking directly to it to upload and download the file blobs securely.

Serve files from Sia

python receipts_endpoint.py

This starts a Tornado server that streams files from Sia when provided with unique file hash.