Configuration

For obtaining the API keys for blockchain access and setting the correct environment variables, please consult this section first and proceed with the next steps.

Create a directory

Let's start with creating a working directory where we store the environment variable file, configuration files, and the scripts.

mkdir my-ocean-project
cd my-ocean-project

Create a .env file

In the working directory create a .env file. The content of this file will store the values for the following variables:

Variable name	Description	Required
OCEAN_NETWORK	Name of the network where the Ocean Protocol's smart contracts are deployed.	Yes
OCEAN_NETWORK_URL	The URL of the Ethereum node (along with API key for non-local networks)**	Yes
PRIVATE_KEY	The private key of the account which you want to use. A private key is made up of 64 hex characters. Make sure you have sufficient balance to pay for the transaction fees.	Yes
AQUARIUS_URL	The URL of the Aquarius. This value is needed when reading an asset from off-chain store.	No
PROVIDER_URL	The URL of the Provider. This value is needed when publishing a new asset or update an existing asset.	No

Treat this file as a secret and do not commit this file to git or share the content publicly. If you are using git, then include this file name in .gitignore file.

The below tabs show partially filled .env file content for some of the supported networks.

Mainnet

.env

# Mandatory environment variables

OCEAN_NETWORK=mainnet
OCEAN_NETWORK_URL=<replace this>
PRIVATE_KEY=<secret>

# Optional environment variables

AQUARIUS_URL=https://v4.aquarius.oceanprotocol.com/
PROVIDER_URL=https://v4.provider.oceanprotocol.com

Polygon

.env

# Mandatory environment variables

OCEAN_NETWORK=polygon
OCEAN_NETWORK_URL=<replace this>
PRIVATE_KEY=<secret>

# Optional environment variables

AQUARIUS_URL=https://v4.aquarius.oceanprotocol.com/
PROVIDER_URL=https://v4.provider.oceanprotocol.com

Local (using Barge)

.env

# Mandatory environment variables
OCEAN_NETWORK=development
OCEAN_NETWORK_URL=http://172.15.0.3:8545/
AQUARIUS_URL=http://172.15.0.5:5000
PROVIDER_URL=http://172.15.0.4:8030

# Replace PRIVATE_KEY if needed
PRIVATE_KEY=0xc594c6e5def4bab63ac29eed19a134c130388f74f019bc74b8f4389df2837a58

Replace <replace this> with the appropriate values. You can see all the networks configuration on Oceanjs' config helper.

Setup dependencies

In this step, all required dependencies will be installed.

Installation & Usage

Let's install Ocean.js library into your current project by running:

Terminal

npm init
npm i @oceanprotocol/lib@latest dotenv crypto-js [email protected] @truffle/hdwallet-provider

Create a configuration file

A configuration file will read the content of the .env file and initialize the required configuration objects which will be used in the further tutorials. The below scripts creates a Web3 wallet instance and an Ocean's configuration object.

Create the configuration file in the working directory i.e. at the same path where the .env is located.

config.js

config.js

require("dotenv").config();
const {
	Aquarius,
	ConfigHelper,
	configHelperNetworks,
} = require("@oceanprotocol/lib");
const ethers = require("ethers");
import fs from "fs";
import { homedir } from "os";

async function oceanConfig() {
	const provider = new ethers.providers.JsonRpcProvider(
		process.env.OCEAN_NETWORK_URL || configHelperNetworks[1].nodeUri
	);
	const publisherAccount = new ethers.Wallet(process.env.PRIVATE_KEY, provider);

	let oceanConfig = new ConfigHelper().getConfig(
		parseInt(String((await publisherAccount.provider.getNetwork()).chainId))
	);
	const aquarius = new Aquarius(oceanConfig?.metadataCacheUri);

	// If using local development environment, read the addresses from local file.
	// The local deployment address file can be generated using barge.
	if (process.env.OCEAN_NETWORK === "development") {
		const addresses = JSON.parse(
			// eslint-disable-next-line security/detect-non-literal-fs-filename
			fs.readFileSync(
				process.env.ADDRESS_FILE ||
					`${homedir}/.ocean/ocean-contracts/artifacts/address.json`,
				"utf8"
			)
		).development;

		oceanConfig = {
			...oceanConfig,
			oceanTokenAddress: addresses.Ocean,
			fixedRateExchangeAddress: addresses.FixedPrice,
			dispenserAddress: addresses.Dispenser,
			nftFactoryAddress: addresses.ERC721Factory,
			opfCommunityFeeCollector: addresses.OPFCommunityFeeCollector,
		};
	}

	oceanConfig = {
		...oceanConfig,
		publisherAccount: publisherAccount,
		consumerAccount: publisherAccount,
		aquarius: aquarius,
	};

	return oceanConfig;
}

module.exports = {
	oceanConfig,
};

Now you have set up the necessary files and configurations to interact with Ocean Protocol's smart contracts using ocean.js. You can proceed with further tutorials or development using these configurations.