Environment Setup

Summary

In this section, you will create your new project directory, your .env file to store your, Hedera Testnet account ID and private keys and set up your Hedera Testnet client.

Prerequisites:

Note: You can always check the "Code Check ✅ " section at the bottom of each page to view the entire code if you run into issues. You can also post your issue to the respective SDK channel in our Discord community here or on the GitHub repository here.

Step 1: Create your project directory

Open your IDE of choice and follow the below steps to create your new project directory.

Create a new Gradle project and name it HederaExamples. Add the following dependencies to your build.gradle file.

build.gradle
dependencies {

    implementation 'com.hedera.hashgraph:sdk:2.19.0'
    implementation 'io.grpc:grpc-netty-shaded:1.46.0'
    implementation 'io.github.cdimascio:dotenv-java:2.3.2'
    implementation 'org.slf4j:slf4j-nop:2.0.3'
    implementation 'com.google.code.gson:gson:2.8.8'

}

Step 2: Install Dependencies and SDKs

Create a new Java class and name it something like HederaExamples. Import the following classes to use in your example:

import com.hedera.hashgraph.sdk.AccountId;
import com.hedera.hashgraph.sdk.Client;
import com.hedera.hashgraph.sdk.PrivateKey;
import io.github.cdimascio.dotenv.Dotenv;
import com.hedera.hashgraph.sdk.HederaPreCheckStatusException;
import com.hedera.hashgraph.sdk.HederaReceiptStatusException;
import com.hedera.hashgraph.sdk.TransactionResponse;
import com.hedera.hashgraph.sdk.TransferTransaction;
import com.hedera.hashgraph.sdk.PublicKey;
import com.hedera.hashgraph.sdk.AccountCreateTransaction;
import com.hedera.hashgraph.sdk.Hbar;
import com.hedera.hashgraph.sdk.AccountBalanceQuery;
import com.hedera.hashgraph.sdk.AccountBalance;

import java.util.concurrent.TimeoutException;

Within the main method, grab your testnet account ID and private key from the .env file.

public class HederaExamples {

    public static void main(String[] args) {

        //Grab your Hedera Testnet account ID and private key
        AccountId myAccountId = AccountId.fromString(Dotenv.load().get("MY_ACCOUNT_ID"));
        PrivateKey myPrivateKey = PrivateKey.fromString(Dotenv.load().get("MY_PRIVATE_KEY"));  
    }
}

Note: You may choose to install the latest version of the SDK here.

Step 3: Create your .env File

The .env file stores your environment variables, account ID and private key (DER encoded). Create the file in your project's root directory.

Note: Testnet HBAR is required for this next step. Please follow the instructions to create a Hedera account on the portal before you move on to the next step.

Grab the Hedera Testnet account ID and DER encoded private key from your Hedera portal profile(see screenshot above) and assign them to the MY_ACCOUNT_ID and MY_PRIVATE_KEY environment variables in your .env file:

MY_ACCOUNT_ID=ENTER TESTNET ACCOUNT ID 
MY_PRIVATE_KEY=ENTER TESTNET PRIVATE KEY

Step 4: Create your Hedera Testnet client

Create a Hedera Testnet client and set the operator information using the testnet account ID and private key for transaction and query fee authorization. The operator is the default account that will pay for the transaction and query fees in HBAR. You will need to sign the transaction or query with the private key of that account to authorize the payment. In this case, the operator ID is your testnet account ID and the operator private key is the corresponding testnet account private key.

//Create your Hedera Testnet client
Client client = Client.forTestnet();
client.setOperator(myAccountId, myPrivateKey);

Note: The client has a default max transaction fee of 100,000,000 tinybars (1 HBAR) and default max query payment of 100,000,000 tinybars (1 HBAR). If you need to change these values, you can use.setDefaultMaxTransactionFee() for a transaction and .setDefaultMaxQueryPayment() for queries. You are only charged the actual cost of the transaction or query.

Code Check

This is what your code should look like:

Java
HederaExamples.java
import com.hedera.hashgraph.sdk.AccountId;
import com.hedera.hashgraph.sdk.Client;
import com.hedera.hashgraph.sdk.PrivateKey;
import io.github.cdimascio.dotenv.Dotenv;
import com.hedera.hashgraph.sdk.HederaPreCheckStatusException;
import com.hedera.hashgraph.sdk.HederaReceiptStatusException;
import com.hedera.hashgraph.sdk.TransactionResponse;
import com.hedera.hashgraph.sdk.TransferTransaction;
import com.hedera.hashgraph.sdk.PublicKey;
import com.hedera.hashgraph.sdk.AccountCreateTransaction;
import com.hedera.hashgraph.sdk.Hbar;
import com.hedera.hashgraph.sdk.AccountBalanceQuery;
import com.hedera.hashgraph.sdk.AccountBalance;

import java.util.concurrent.TimeoutException;

public class HederaExamples {

    public static void main(String[] args) {

        //Grab your Hedera Testnet account ID and private key
        AccountId myAccountId = AccountId.fromString(Dotenv.load().get("MY_ACCOUNT_ID"));+
        PrivateKey myPrivateKey = PrivateKey.fromString(Dotenv.load().get("MY_PRIVATE_KEY"));

        //Create your Hedera Testnet client
        Client client = Client.forTestnet();
        client.setOperator(myAccountId, myPrivateKey);

    }
}
JavaScript
index.js
const {
  Client,
  PrivateKey,
  AccountCreateTransaction,
  AccountBalanceQuery,
  Hbar,
  TransferTransaction,
} = require("@hashgraph/sdk");

require("dotenv").config();

async function main() {
  //Grab your Hedera testnet account ID and private key from your .env file
  const myAccountId = process.env.MY_ACCOUNT_ID;
  const myPrivateKey = process.env.MY_PRIVATE_KEY;

  // If we weren't able to grab it, we should throw a new error
  if (!myAccountId || !myPrivateKey) {
    throw new Error(
      "Environment variables MY_ACCOUNT_ID and MY_PRIVATE_KEY must be present"
    );
  }

  // Create our connection to the Hedera network
  // The Hedera JS SDK makes this really easy!
  const client = Client.forTestnet();
  client.setOperator(myAccountId, myPrivateKey);
}
main();
Go
hedera_examples.go
package main

import (
    "fmt"
    "os"

    "github.com/hashgraph/hedera-sdk-go/v2"
    "github.com/joho/godotenv"
)

func main() {

    //Loads the .env file and throws an error if it cannot load the variables from that file correctly
    err := godotenv.Load(".env")
    if err != nil {
        panic(fmt.Errorf("Unable to load environment variables from .env file. Error:\n%v\n", err))
    }

    //Grab your testnet account ID and private key from the .env file
    myAccountId, err := hedera.AccountIDFromString(os.Getenv("MY_ACCOUNT_ID"))
    if err != nil {
        panic(err)
    }

    myPrivateKey, err := hedera.PrivateKeyFromString(os.Getenv("MY_PRIVATE_KEY"))
    if err != nil {
        panic(err)
    }

    //Print your testnet account ID and private key to the console to make sure there was no error
    fmt.Printf("The account ID is = %v\n", myAccountId)
    fmt.Printf("The private key is = %v\n", myPrivateKey)

    //Create your testnet client
    client := hedera.ClientForTestnet()
    client.SetOperator(myAccountId, myPrivateKey)
}

Have a question? Ask it on StackOverflow

Last updated

Was this helpful?

#2165: #325 update writer/author cards

Change request updated