casper-go-sdk

README

Casper Go SDK

The Casper Go SDK provides a convenient way to interact with the Casper Network using the Go.

Get started

go get github.com/make-software/casper-go-sdk

Base usage

RPC client

Package rpc provides access to the exported methods of RPC Client and data structures where serialized response. See more details here

Example:

package main

import (
	"context"
	"fmt"
	"net/http"

	"github.com/make-software/casper-go-sdk/casper"
)

func main() {
	handler := casper.NewRPCHandler("https://casper-node-proxy.dev.make.services/rpc", http.DefaultClient)
	client := casper.NewRPCClient(handler)
	deployHash := "62972eddc6fdc03b7ec53e52f7da7e24f01add9a74d68e3e21d924051c43f126"
	deploy, err := client.GetDeploy(context.Background(), deployHash)
	if err != nil {
		return
	}
	fmt.Println(deploy.Deploy.Hash)
}

SSE

SSE package provide basic functionality to work with Casper events that streamed by SSE server. See more details here

Example:

package main

import (
	"context"
	"log"

	"github.com/make-software/casper-go-sdk/sse"
)

func main() {
	client := sse.NewClient("https://casper-node-proxy.dev.make.services/events/main")
	defer client.Stop()
	client.RegisterHandler(
		sse.DeployProcessedEventType,
		func(ctx context.Context, rawEvent sse.RawEvent) error {
			deploy, err := rawEvent.ParseAsDeployProcessedEvent()
			if err != nil {
				return err
			}
			log.Printf("Deploy hash: %s", deploy.DeployProcessed.DeployHash)
			return nil
		})
	lastEventID := 1234
	client.Start(context.TODO(), lastEventID)
}

Work with Casper types

SDK implements base functionality that allows to work with native Casper types.

• High-level types declaration and the base functions to construct them. details
• Low level types (CLValue) with base functionality details
• Identifiers, hashes and related functions details
• Cryptography public and private keys functionality details

Example how to construct deploy and push it to the network:

package main

import (
	"context"
	"encoding/hex"
	"log"
	"math/big"
	"net/http"

	"github.com/make-software/casper-go-sdk/casper"
	"github.com/make-software/casper-go-sdk/types/clvalue"
)

func main() {
	accountPublicKey, err := casper.NewPublicKey("012488699f9a31e36ecf002675cd7186b48e6a735d10ec1b308587ca719937752c")
	if err != nil { return }
	amount := big.NewInt(100000000)
	session := casper.ExecutableDeployItem{
		ModuleBytes: &casper.ModuleBytes{
			ModuleBytes: hex.EncodeToString([]byte("<<<Contract Wasm>>>")),
			Args: (&casper.Args{}).
				AddArgument("target", clvalue.NewCLByteArray(accountPublicKey.AccountHash().Bytes())).
				AddArgument("amount", *clvalue.NewCLUInt512(amount)),
		},
	}

	payment := casper.StandardPayment(amount)

	deployHeader := casper.DefaultHeader()
	deployHeader.Account = accountPublicKey
	deployHeader.ChainName = "test-net"

	newDeploy, err := casper.MakeDeploy(deployHeader, payment, session)

	handler := casper.NewRPCHandler("https://casper-node-proxy.dev.make.services/rpc", http.DefaultClient)
	client := casper.NewRPCClient(handler)
	result, err := client.PutDeploy(context.Background(), *newDeploy)
	
	log.Println(result.DeployHash)
}

Advanced usage

It is crucial to have a clear understanding of the concept in order to avoid common mistakes or misuse of functionality. The SDK consists of several packages that have strict dependencies.

If we were to present the packages in different layers, the structure would be as follows (in ascending order, from low to high):

1. Lowest layer: cltype and keypair
2. key
3. clvalue
4. types
5. Services rpc and sse
6. Higher level is a Facade to popular interfaces casper

The Dependency tree can help to visualise:

Links to package documentation and examples:

1. cltype examples
2. clvalue doc | examples
3. keypair doc | examples
4. types doc | examples
5. rpc doc | examples
6. sse doc | examples

Lint and test

Install go tools:

go install -v github.com/incu6us/goimports-reviser/v3@latest
go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.50.1

Run linters:

go fmt ./...
go vet ./...
goimports-reviser ./...
golangci-lint run

Run tests:

go test ./...