Getting Started with Corda

Corda is a distributed ledger technology first developed with businesses in mind. This step-by-step guide will get you started on it.

Corda is a distributed ledger technology (DLT) designed for business applications, particularly in financial services. To construct interoperable blockchain networks that conduct transactions in complete secrecy, Corda is your only option. Businesses can engage in direct, valuable transactions with the help of Corda’s smart contract technology

Here’s a step-by-step guide to get you started.

Step 1: Prerequisites

Before diving into Corda, ensure you have the following.

• Java 8 or later: Corda is built on Java, so make sure it’s installed and properly configured.
• IDE: Any Java IDE like IntelliJ IDEA or Eclipse will work. IntelliJ IDEA is the most recommended because it has good support for Kotlin, which Corda uses extensively.
• Corda tools: You’ll also need to install the Corda command line interface (CLI) and Docker for running Corda nodes.

Step 2: Install Java and set up environment

Install Java

• Download and install Java 8 or higher from Oracle’s website or use OpenJDK.
• Set the JAVA_HOME environment variable to the installed Java path.

Verify Java installation by running:

java -version

Install Kotlin (optional, but helpful for Corda development): Corda is built with Kotlin, so having Kotlin set up in your IDE can help. You can download Kotlin from https://kotlinlang.org/

Step 3: Install IntelliJ IDEA

• Download and install IntelliJ IDEA Community Edition from https://www.jetbrains.com/idea/download/?section=windows
• Install the Corda plugin in IntelliJ. This plugin will help you set up and manage Corda projects easily.

Step 4: Download and set up Corda

Corda has several versions, including ‘Corda Open Source’ and ‘Corda Enterprise’. You can start with Corda Open Source for development purposes.

Download Corda

Visit https://github.com/corda/corda or https://r3.com/get-corda/ and download the latest version of Corda.

Corda example projects

You can clone a Corda example project to understand the structure. For example:

bash
CopyEdit
git clone https://github.com/corda/samples
cd samples/cordapp-example

Step 5: Set up Corda nodes

In Corda, nodes represent the individual participants in the distributed network. Each node runs a Corda service, which interacts with other nodes.

Run the Corda network

To run a basic Corda network, you can use Docker. The Corda team provides Docker containers to easily start nodes. For example, you can use the Corda network from the Corda Network Docker GitHub repository.

Install Docker and run the network:

git clone https://github.com/corda/corda-docker
cd corda-docker
docker-compose up

Running Corda nodes

Once the Docker containers are running, the nodes in the network will automatically connect to each other. You can interact with them using the Corda shell.

Step 6: Create your first Corda CorDapp

A CorDapp (Corda Distributed Application) is the application that you will develop to run on the Corda network.

Create a new CorDapp project

Use the Corda templates or create a new project manually in IntelliJ. To create a new project:

• Open IntelliJ IDEA and create a new project.
• Select Kotlin as the language and configure the project settings.

Define the CorDapp

• Create a contract that defines the rules of your distributed application (business logic).
• Create a flow that defines how the participants interact with each other.
• Write tests to simulate the interaction between nodes.

Here’s an example structure for a CorDapp:

my-cordapp
├── build.gradle
├── src
│   ├── main
│   │   ├── kotlin
│   │   │   ├── com
│   │   │   │   ├── example
│   │   │   │   │   ├── contract
│   │   │   │   │   └── flow
│   │   │   │   ├── util
│   └── test
│       └── kotlin

Example flow

Here’s a basic example of how a flow may look in Corda:

@StartableByRPC
@InitiatingFlow
class ExampleFlow : FlowLogic<String>() {
    @Suspendable
    override fun call(): String {
        return “Hello, Corda!”
    }
}

Create a contract

Contracts define the rules that govern transactions in Corda. Here’s a simple contract example:

class ExampleContract : Contract {
    companion object {
        const val ID = “com.example.contract.ExampleContract”
    }

    override fun verify(tx: TransactionForVerification) {
        // Custom verification logic
    }
}

Step 7: Deploy the CorDapp

Once your CorDapp is ready:

Build the CorDapp

Run the following Gradle command to build the project:

./gradlew build

Deploy the CorDapp

The CorDapp .jar files need to be deployed to the nodes. You can copy them into the corda-apps directory of each node.

Run the flow

Use the Corda shell to invoke your flow:

run flowExample.ExampleFlow

Step 8: Interact with the network

You can interact with the network using the Corda shell or through a web interface. The Corda shell allows you to issue commands like sending transactions, invoking flows, and viewing node information.

Successfully configuring the Corda platform paves the way for creating and releasing distributed applications (CorDapps) that are safe, scalable, and privacy-preserving. We have established a solid foundation for permissioned blockchain solutions by setting up the notary and network map service, configuring the network parameters, and installing Corda nodes. This configuration allows for smooth peer-to-peer communications that are both secure and compliant with enterprise-level standards.