Espace Files

Espace Files is a proof of concept for hybrid decentralization in file storage services, which utilizes the Ethereum blockchain and IPFS.

By combining the benefits of centralization (security and speed) with those of decentralization (non-deletable and incorruptible data), hybrid decentralization allows us to store a file in the IPFS network with the Ethereum blockchain for life, while also enabling fast and secure access.

Decentralization

Decentralization involves:

• Using the InterPlanetary File System (IPFS) network to save file contents, which are encrypted using the AES 256 algorithm.
• Storing IPFS CID in an Ethereum blockchain as a smart contract (File.sol).

Centralization

The (PostgreSQL database) is used solely to store file encryption data, such as authentication tags, keys, and salts. Please note that the encryption data itself is encrypted in the database using PGP symmetric key.

Authentication

Use JSON Web Token (HMACSHA512) with an expiration time of 10 hours.

Storage Service

The Storage Service is an Espace Files SaaS API that uses an API Auth/Key combination.

Required environments

Name	Description	Example
ETH_BLOCKCHAIN_ADDRESS	Ethereum Goerli testnet blockchain HTTP address	http://localhost:8545
ETH_ACCOUNT	Ethereum Goerli testnet account address	0x12...
ETH_ACCOUNT_MNEMOMIC	Ethereum Goerli testnet account mnemonic	planet sentence ...
INFURA_IPFS_API_KEY	IPFS Infura project API key	xxx
INFURA_IPFS_API_KEY_SECRET	IPFS Infura project API key secret	xxx
DATABASE_URL	PostgreSQL Database URL	postgres://postgres:root@localhost:5432/espacefiles
DATABASE_ENCRYPTION_KEY	PostgreSQL PGP symmetric key used to encrypt/decrypt data related to files encryption	random12345
DATABASE_ENCRYPTION_ALT_KEY	PostgreSQL PGP symmetric key used to encrypt/decrypt data related to Storage Service	random12345
JWT_KEY	Key used for JSON Web Token signing	random12345
CORS_URL	Cross-origin resource sharing allowed origin	https://example.com
PORT	HTTP Server port	8080

Database

To use the PostgreSQL database, please complete the DDL available in database/ddl.sql

Get started (local)

1. Install dependencies

$ npm ci

2. Run Blockchain in local

   1. Download https://www.trufflesuite.com/ganache (recommended)
   2. Or using ganache-cli:

      $ npm install -g ganache-cli && ganache-cli

3. Compile and migrate Solidity smart contracts

$ truffle compile && truffle migrate

4. Set up DDL in your database, see database/ddl.sql

5. Launch server

$ npm run start:dev

Get started (production-like using Goerli testnet)

1. Install dependencies

$ npm ci

2. Run tests

$ npm run test

3. Compile and migrate Solidity smart contracts

$ truffle compile && truffle migrate --network goerli

4. Set up DDL in your database, see database/ddl.sql

5. Launch server (using PM2)

$ pm2 start npm --name "api" -- run "build_and_start:prod"

6. Access to PM2

$ pm2 monit

License

This project is licensed with GNU AGPL v3 License.
See LICENSE for more details.