Golang has recently started making rapid strides in the programming and application development world. With the latest version releases, Golang has seen the inclusion of several new features. This has led to its huge popularity among the developers.
But why Go blockchain development? In brief, Go is designed to handle multi-core CPU architecture, big scaled servers, and distributed services. This makes it possible for developers to easily create a number of goroutines.
Without further ado, let’s concentrate on the Golang connection to an Ethereum client.
How to Make a Connection to an Ethereum Client Using Golang?
- Golang is renowned for its stable libraries and CSP concurrency model. Furthermore, there is also a Golang-based Ethereum client available. It goes by the name of Geth. In case you wish to gain a further insight into Go Ethereum, you should definitely visit the link: https://geth.ethereum.org/.
- In this tutorial blog, we will utilize the Go programming language to make a connection to an Ethereum client. Hence, we will make use of Infura. You can connect to the Ethereum node via this service that is provided to the developers by consensus. In addition to this, you can connect test nets as well.
How to Create a New Directory for Connecting to an Ethereum Client?
You will get access to the entire codebase at Github: https://github.com/GolangCompany/ethDApp.
- First, we will create a new directory ethDApp. As a rule of thumb, I save all of my projects in go-workspace. I’ll use the Command Prompt as I’m utilizing a Windows computer to create the directory. You must use Terminal if you’re using Linux or a Mac.
cd go-workspace
mkdir ethDApp
cd ethDApp
code .
- I’ll be using VS Code as my choice of IDE. You can go for any other IDEs or text editors like GoLand, Vim-go, Zeus IDE, etc.
In the meantime, if you are having trouble building a ledger, an NFT marketplace, or tokens, don’t give up. You will obtain the much-needed help with Go blockchain development by simply getting in contact with the developers affiliated with Golang.company.
How to Begin Programming for Making a Connection to an Ethereum Client?
- We’ll make a Go source file called “main.go” in the directory “ethDApp” of Visual Studio Code. The Go application’s entry point to connect to the Ethereum node will begin with this.
- Let us commence the programming part.
package main
import (
“context”
“fmt”
“log”
“github.com/ethereum/go-ethereum/common”
“github.com/ethereum/go-ethereum/ethclient”
)
- As you can see, we have imported a bunch of libraries. These are “log”, “fmt”, “context”, “github.com/ethereum/go-ethereum/common” and “github.com/ethereum/go-ethereum/ethclient.”
- However, before getting started with the program, we have to initialize the project with the help of go mod init.
go mod init github.com/golang-company/ethDApp
What this will do is create a go.mod file.
- Following this, we will install the packages and dependencies. These are: github.com/ethereum/go-ethereum/common and github.com/ethereum/go-ethereum/ethclient. And in order to do so, we will type in the Terminal:
go get github.com/ethereum/go-ethereum/common
This will lead to the downloading of the dependencies.
Furthermore, we will type:
go get github.com/ethereum/go-ethereum/ethclient
- Next, we’ll move on to the main function, which serves as the program’s entry point. Connecting to the Ethereum node is the first thing you need to do. As a result, we will use the term “ethclient.Dial” here and supply an endpoint that points to an Ethereum node. We’ll make use of the Infura node in this case.
- For this instance, we’ll replicate the endpoint and utilize the MAINNET. After ethclient.Dial, we will paste the endpoint.
So, we have to type:
ethclient.Dial(“https://mainnet.infura.io/v3/03bf216d226d47adb501d642f9dc0c12”)
- In the next step, we have to store the Dial function’s return value. There are two potential values. The connection itself is the first, and any errors it could run into are the second. Thus, we write the above statement as:
connection, err := ethclient.Dial(“https://mainnet.infura.io/v3/03bf216d226d47adb501d642f9dc0c12”)
- Go’s error handling differs slightly from those of other programming languages. The err variable must be verified to see if it contains anything, as indicated.
if err != nil {
log.Fatal (“Failed to make a connection to the Ethereum Node”, err)
As a result, if the error is not nil, we will simply report that a connection attempt failed and then provide the actual problem (err) to the log statement.
- We must first establish a context “context” in order to leverage concurrency in Go. We will attempt to obtain a transaction from the Ethereum node using the “context” we have established. This will facilitate the establishment of communication between the application and the Ethereum node. To achieve this, we’ll put the following statements in VS Code:
context := context. Background()
txn, pending, _ := connection.TransactionByHash (context, common.HexToHash (“0xbca59819540b55e32a9a422e44559df023c2951b97b50815fa029b67ffe2a4a7”)
The context is the first input we provide in the second line, and the second parameter is the transaction hash itself that we want to search for. Using the common library, we are able to change the transaction hash from hex to hash at this point. We call it common.HexToHash.
I browse a random transaction using Etherscan in order to accomplish this, copy the transaction hash, and then paste it into the statement.
- A few things have been returned. These are the pending flag (which is a boolean flag) and txn. The transaction is considered to be pending if the pending flag is true. If it is false, the transaction is not considered to be waiting. We shall use the if-else statement for this.
if pending {
fmt.Println(“The transaction is pending”, txn)
} else{
fmt.Println(“Transaction is not pending”, txn)
}
}
- We will publish a statement along with the text message if it is pending. If the condition is not satisfied, we print out the words “Transaction Not Pending” next to the txn.
If you wish to see the output, you get:
Hopefully, you were able to comprehend the concept properly. In order to connect to Ethereum using the Go programming language, you must carry out the above-mentioned steps. If you get the reasoning behind each stage properly, the procedure is actually fairly straightforward. And you should concentrate on the coding if you want to fully understand the idea. You’ll get more skilled with more practice.
