feat(prover): guardian prover startup (#529)

Co-authored-by: maskpp <[email protected]>

prover/guardian_prover_sender/guardian_prover.go

@@ -34,6 +34,14 @@ type signedBlockReq struct {
 	Prover    common.Address `json:"proverAddress"`
 }
 
+// startupReq is the request body send to the health check server when the guardian prover starts up.
+type startupReq struct {
+	ProverAddress string `json:"prover"`
+	Version       string `json:"version"`
+	Revision      string `json:"revision"`
+	Signature     []byte `json:"signature"`
+}
+
 // GuardianProverBlockSender is responsible for signing and sending known blocks to the health check server.
 type GuardianProverBlockSender struct {
 	privateKey                *ecdsa.PrivateKey
@@ -88,7 +96,7 @@ func (s *GuardianProverBlockSender) post(ctx context.Context, route string, req
 
 // SignAndSendBlock signs the given block and sends it to the health check server.
 func (s *GuardianProverBlockSender) SignAndSendBlock(ctx context.Context, blockID *big.Int) error {
-	signed, header, err := s.sign(ctx, blockID)
+	signed, header, err := s.signBlock(ctx, blockID)
 	if err != nil {
 		return nil
 	}
@@ -110,6 +118,41 @@ func (s *GuardianProverBlockSender) SignAndSendBlock(ctx context.Context, blockI
 	)
 }
 
+func (s *GuardianProverBlockSender) SendStartup(ctx context.Context, revision string, version string) error {
+	if s.healthCheckServerEndpoint == nil {
+		log.Info("No health check server endpoint set, returning early")
+		return nil
+	}
+
+	sig, err := crypto.Sign(
+		crypto.Keccak256Hash(
+			s.proverAddress.Bytes(),
+			[]byte(revision),
+			[]byte(version)).Bytes(),
+		s.privateKey)
+	if err != nil {
+		return err
+	}
+
+	req := &startupReq{
+		Revision:      revision,
+		Version:       version,
+		ProverAddress: s.proverAddress.Hex(),
+		Signature:     sig,
+	}
+
+	if err := s.post(ctx, "startup", req); err != nil {
+		return err
+	}
+
+	log.Info("Guardian prover successfully sent startup",
+		"revision", revision,
+		"version", version,
+	)
+
+	return nil
+}
+
 // sendSignedBlockReq is the actual method that sends the signed block to the health check server.
 func (s *GuardianProverBlockSender) sendSignedBlockReq(
 	ctx context.Context,
@@ -139,7 +182,7 @@ func (s *GuardianProverBlockSender) sendSignedBlockReq(
 }
 
 // sign signs the given block and returns the signature and header.
-func (s *GuardianProverBlockSender) sign(ctx context.Context, blockID *big.Int) ([]byte, *types.Header, error) {
+func (s *GuardianProverBlockSender) signBlock(ctx context.Context, blockID *big.Int) ([]byte, *types.Header, error) {
 	log.Info("Guardian prover signing block", "blockID", blockID.Uint64())
 
 	head, err := s.rpc.L2.BlockNumber(ctx)

prover/guardian_prover_sender/interface.go

@@ -7,6 +7,7 @@ import (
 
 type BlockSigner interface {
 	SignAndSendBlock(ctx context.Context, blockID *big.Int) error
+	SendStartup(ctx context.Context, revision string, version string) error
 }
 
 type Heartbeater interface {

prover/prover.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"math/big"
 	"net/http"
+	"runtime/debug"
 	"sync"
 	"time"
 
@@ -400,6 +401,15 @@ func (p *Prover) Start() error {
 	}()
 
 	if p.IsGuardianProver() {
+		revision, version, err := getRevision()
+		if err != nil {
+			log.Crit("Unable to get revision", "error", err)
+		}
+
+		if err := p.guardianProverSender.SendStartup(p.ctx, revision, version); err != nil {
+			log.Crit("Failed to send guardian prover startup", "error", err)
+		}
+
 		p.wg.Add(1)
 		go p.heartbeatInterval(p.ctx)
 	}
@@ -1320,3 +1330,25 @@ func (p *Prover) heartbeatInterval(ctx context.Context) {
 		}
 	}
 }
+
+func getRevision() (string, string, error) {
+	var revision string
+
+	var version string
+
+	if info, ok := debug.ReadBuildInfo(); ok {
+		version = info.Main.Version
+
+		for _, setting := range info.Settings {
+			if setting.Key == "vcs.revision" {
+				revision = setting.Value
+			}
+		}
+	}
+
+	if revision == "" || version == "" {
+		return "", "", fmt.Errorf("unable to get revision or version. revision: %v, version: %v", revision, version)
+	}
+
+	return revision, version, nil
+}