Testnet¶

A blockchain testnet serves as a sandbox environment for developers and users to experiment, test, and deploy smart contracts, decentralized applications (DApps), and other blockchain-related functionalities without using real cryptocurrency or affecting the main blockchain network. Testnets mimic the behavior of the main blockchain but operate with fake or test tokens, allowing users to simulate real-world scenarios and interactions in a risk-free environment. They provide a platform for developers to debug code, identify potential vulnerabilities, and gauge the performance and scalability of their applications before deploying them on the mainnet. Testnets also facilitate collaboration among developers and enable the community to contribute to the improvement and evolution of blockchain protocols and applications through feedback and testing.

Harbinger¶

While anyone has the ability to spin up a testnet, Koinos Group provides a testnet for general use called Harbinger. To target a particular testnet one must retrieve the chain ID. The chain ID prevents your transaction from being valid on any other blockchain other than the one you are targeting.

It is important to retrieve a fresh chain ID from Harbinger when doing work on testnet as it is not uncommon for the testnet to be restarted with a new chain ID. In other words, do not just copy this chain ID, retrieve it yourself before you use it.

curl -d '{"jsonrpc":"2.0", "id":0, "method":"chain.get_chain_id", "params":{}}' 'https://api.harbinger.koinos.pro/jsonrpc?apikey=<APIKEY>'

{
  "jsonrpc": "2.0",
  "result": {
    "chain_id": "EiBncD4pKRIQWco_WRqo5Q-xnXR7JuO3PtZv983mKdKHSQ=="
  },
  "id": 0
}

Using the chain ID retrieved and your preferred Harbinger endpoint, you can use the testnet to deploy contracts and test your dApp. As you know, every action on Koinos requires Mana so we will need to acquire KOIN for testing. On testnet we call it tKOIN.

tKOIN and the faucet¶

tKOIN is the Koinos blockchain testnet token symbol.

Once you have your public address you can join our Discord server and request some tKOIN in the #faucet channel under the Developer section by sending the following message to the faucet bot:

Example of acquiring tKOIN¶

The command to receive tKOIN from the faucet is as follows:

!faucet <public address>

!faucet 1ENxxuH81kytBdYe81fD9tBdYe81fD9Qxe

Transferring 100.000000 tKOIN to address 1ENxxuH81kytBdYe81fD9tBdYe81fD9Qxe.

Example of checking your tKOIN balance¶

The command to check your balance from the faucet is as follows:

!balance <public address>

!balance 1ENxxuH81kytBdYe81fD9BdYe81fD9Qxe

Balance at address 1ENxxuH81kytBdYe81fD9tBdYe81fD9Qxe is 100.000000 tKOIN.