go-ethereum/swarm/pss/client

pss client

simple abstraction for implementing pss functionality

the pss client library aims to simplify usage of the p2p.protocols package over pss

IO is performed using the ordinary p2p.MsgReadWriter interface, which transparently communicates with a pss node via RPC using websockets as transport layer, using methods in the PssAPI class in the swarm/pss package

USAGE

Minimal-ish usage example. It needs a running pss-enabled swarm node to work. Please refer to the test files for more details.

 import (
	"context"
	"fmt"
	"os"
	pss "github.com/ethereum/go-ethereum/swarm/pss/client"
	"github.com/ethereum/go-ethereum/p2p/protocols"
	"github.com/ethereum/go-ethereum/p2p"
	"github.com/ethereum/go-ethereum/pot"
	"github.com/ethereum/go-ethereum/log"
)

type FooMsg struct {
	Bar int
}


func fooHandler (msg interface{}) error {
	foomsg, ok := msg.(*FooMsg)
	if ok {
		log.Debug("Yay, just got a message", "msg", foomsg)
	}
	return fmt.Errorf("Unknown message")
}

spec := &protocols.Spec{
	Name: "foo",
	Version: 1,
	MaxMsgSize: 1024,
	Messages: []interface{}{
		FooMsg{},
	},
}

proto := &p2p.Protocol{
	Name: spec.Name,
	Version: spec.Version,
	Length: uint64(len(spec.Messages)),
	Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
		pp := protocols.NewPeer(p, rw, spec)
		return pp.Run(fooHandler)
	},
}

func implementation() {      
    cfg := pss.NewClientConfig()
    psc := pss.NewClient(context.Background(), nil, cfg)
    err := psc.Start()
    if err != nil {
    	log.Crit("can't start pss client")
    	os.Exit(1)
    }

log.Debug("connected to pss node", "bzz addr", psc.BaseAddr)
    
    err = psc.RunProtocol(proto) 
    if err != nil {
    	log.Crit("can't start protocol on pss websocket")
    	os.Exit(1)
    }
    
    addr := pot.RandomAddress() // should be a real address, of course
    psc.AddPssPeer(addr, spec)
    
    // use the protocol for something
    
    psc.Stop()
} 

BUG(test): TestIncoming test times out due to deadlock issues in the swarm hive