Monetha: Decentralized Reputation Framework

Payment Layer: go-sdk

A Golang SDK for decentralized Monetha Payment Gateway usage.

• Building the source
  • Prerequisites
  • Build
• Usage
  • Installation & setup
• Contributing
  • Making changes
    • Contracts update
    • Formatting source code

Building the source

Prerequisites

1. Make sure you have Git installed.
2. Install Go 1.12
3. Setup $GOPATH environment variable as described here.
4. Clone the repository:

mkdir -p $GOPATH/src/github.com/monetha
cd $GOPATH/src/github.com/monetha
git clone git@github.com:monetha/payment-go-sdk.git
cd payment-go-sdk

Note: You can skip steps 2-3 on Linux and use the official docker image for Go after step 4 to build the project:

docker run -it --rm \
  -v "$PWD":/go/src/github.com/monetha/payment-go-sdk \
  -w /go/src/github.com/monetha/payment-go-sdk \
  golang:1.12 \
  /bin/bash

Build

Install dependencies:

    make dependencies

Usage

In order to better understand the use cases of the payment-go-sdk please refer to Monetha Payment layer: de-centralized usage scenarios. There are as well several code sample on how payment-go-sdk can be used in order to complete a full payment by Customer and Merchant which can be found here

Installation & setup

Install new dependency from you project's folder

go get github.com/monetha/payment-go-sdk

After package is installed import the package in your working file

import (
    "github.com/ethereum/go-ethereum"
    eth "github.com/mometha/go-ethereum"
    "github.com/monetha/payment-go-sdk/processor"
    "github.com/monetha/payment-go-sdk/wallet"
)

Initializing processor and wallet

backend, err := ethclient.Dial("ETHEREUM_RPC_URL")
if err != nil {
    // Handle the error
}

e := eth.New(backend, log.Printf)

merchantAccount, err := crypto.HexToECDSA("MERCHANT_PRIVATE_KEY")
if err != nil {
   // Handle the error
}

session = e.NewSession(merchantAccount)

processorContractAddress := common.HexToAddress("PAYMENT_PROCESSOR_CONTRACT_ADDRESS")

processor := processor.NewProcessor(session , processorContractAddress)

walletAddress := common.HexToAddress("MERCHANT_WALLET_ADDRESS")

wallet := wallet.NewWallet(session, walletAddress)

• ETHEREUM_RPC_URL - Ethereum network node RPC url
• MERCHANT_PRIVATE_KEY - Merchant's Ehereum private key. This address will be covering operational costs
• PAYMENT_PROCESSOR_CONTRACT_ADDRESS - PaymentProcessor contract address that is provided by Monetha
• MERCHANT_WALLET_ADDRESS - MerchantWallet contract address that is provided by Monetha

Note: Currently all PaymentProcessor and MerchantWallet contract instances are provided by Monetha. Contact team@monetha.io in case if you would like to have your own instance deployed.

After the following code is initialized you are ready to execute all processor and wallet methods. All methods will be executed by Merchant's account.

More information on methods available can be found in godocs

Contributing

Thank you for considering to help out with the source code! We welcome contributions from anyone on the internet, and are grateful for even the smallest of fixes! If you'd like to contribute to payment-go-sdk, please fork, fix, commit and send a pull request for the maintainers to review and merge into the main code base. Feel free to register issues and suggestions.

Making changes

Make your changes, then ensure that the linters passes:

    make lint

Contracts update

This SDK is dependent on Monetha's payment layer smart contracts. In case if contracts will be updated and method signatures will change contracts/MerchantWallet.go and contracts/PaymentProcessor.go files need to be re-generated. To do so follow the steps below:

1. Copy all necessary smart contract build artifacts of github.com/monetha/payment-contracts to contracts/code folder.
2. Run go generate command in contracts folder to convert Ethereum contracts into Go package.
3. Commit new/updated files.

Formatting source code

make fmt command automatically formats Go source code of the entire project.