[Checkpointing] JSON RPC point for generating exit proofs (#844)

* JSON RPC point for generating exit proofs

* Comments fix

consensus/consensus.go

@@ -34,6 +34,9 @@ type Consensus interface {
 	// GetSyncProgression retrieves the current sync progression, if any
 	GetSyncProgression() *progress.Progression
 
+	// GetBridgeProvider returns an instance of BridgeDataProvider
+	GetBridgeProvider() BridgeDataProvider
+
 	// Initialize initializes the consensus (e.g. setup data)
 	Initialize() error
 
@@ -75,3 +78,9 @@ type Params struct {
 
 // Factory is the factory function to create a discovery consensus
 type Factory func(*Params) (Consensus, error)
+
+// BridgeDataProvider is an interface providing bridge related functions
+type BridgeDataProvider interface {
+	// GenerateExit proof generates proof of exit for given exit event
+	GenerateExitProof(exitID, epoch, checkpointBlock uint64) ([]types.Hash, error)
+}

consensus/dev/dev.go

@@ -242,3 +242,7 @@ func (d *Dev) Close() error {
 
 	return nil
 }
+
+func (d *Dev) GetBridgeProvider() consensus.BridgeDataProvider {
+	return nil
+}

consensus/dummy/dummy.go

@@ -75,6 +75,10 @@ func (d *Dummy) Close() error {
 	return nil
 }
 
+func (d *Dummy) GetBridgeProvider() consensus.BridgeDataProvider {
+	return nil
+}
+
 func (d *Dummy) run() {
 	d.logger.Info("started")
 	// do nothing

consensus/ibft/ibft.go

@@ -532,6 +532,11 @@ func (i *backendIBFT) SetHeaderHash() {
 	}
 }
 
+// GetBridgeProvider returns an instance of BridgeDataProvider
+func (i *backendIBFT) GetBridgeProvider() consensus.BridgeDataProvider {
+	return nil
+}
+
 // updateCurrentModules updates Signer, Hooks, and Validators
 // that are used at specified height
 // by fetching from ForkManager

consensus/polybft/consensus_runtime.go

@@ -780,8 +780,8 @@ func (c *consensusRuntime) getExitEventRootHash(epoch uint64) (types.Hash, error
 	return tree.Hash(), nil
 }
 
-// generateExitProof generates proof of exit
-func (c *consensusRuntime) generateExitProof(exitID, epoch, checkpointBlock uint64) ([]types.Hash, error) {
+// GenerateExitProof generates proof of exit
+func (c *consensusRuntime) GenerateExitProof(exitID, epoch, checkpointBlock uint64) ([]types.Hash, error) {
 	exitEvent, err := c.state.getExitEvent(exitID, epoch, checkpointBlock)
 	if err != nil {
 		return nil, err

consensus/polybft/consensus_runtime_test.go

@@ -1671,7 +1671,7 @@ func TestConsensusRuntime_getExitEventRootHash(t *testing.T) {
 	})
 }
 
-func TestConsensusRuntime_generateExitProof(t *testing.T) {
+func TestConsensusRuntime_GenerateExitProof(t *testing.T) {
 	const (
 		numOfBlocks         = 10
 		numOfEventsPerBlock = 2
@@ -1689,7 +1689,7 @@ func TestConsensusRuntime_generateExitProof(t *testing.T) {
 	tree, err := NewMerkleTree(checkpointEvents)
 	require.NoError(t, err)
 
-	proof, err := runtime.generateExitProof(1, 1, 1)
+	proof, err := runtime.GenerateExitProof(1, 1, 1)
 	require.NoError(t, err)
 	require.NotNil(t, proof)
 
@@ -1707,7 +1707,7 @@ func TestConsensusRuntime_generateExitProof(t *testing.T) {
 	})
 
 	t.Run("Generate exit proof - no event", func(t *testing.T) {
-		_, err := runtime.generateExitProof(21, 1, 1)
+		_, err := runtime.GenerateExitProof(21, 1, 1)
 		require.ErrorContains(t, err, "could not find any exit event that has an id")
 	})
 }

consensus/polybft/polybft.go

@@ -618,6 +618,11 @@ func (p *Polybft) PreCommitState(_ *types.Header, _ *state.Transition) error {
 	return nil
 }
 
+// GetBridgeProvider returns an instance of BridgeDataProvider
+func (p *Polybft) GetBridgeProvider() consensus.BridgeDataProvider {
+	return p.runtime
+}
+
 type pbftTransportWrapper struct {
 	topic *network.Topic
 }

jsonrpc/bridge_endpoint.go

@@ -0,0 +1,20 @@
+package jsonrpc
+
+import (
+	"github.com/0xPolygon/polygon-edge/types"
+)
+
+// bridgeStore interface provides access to the methods needed by bridge endpoint
+type bridgeStore interface {
+	GenerateExitProof(exitID, epoch, checkpointBlock uint64) ([]types.Hash, error)
+}
+
+// Bridge is the bridge jsonrpc endpoint
+type Bridge struct {
+	store bridgeStore
+}
+
+// GenerateExitProof generates exit proof for given exit event
+func (b *Bridge) GenerateExitProof(exitID, epoch, checkpointBlock argUint64) (interface{}, error) {
+	return b.store.GenerateExitProof(uint64(exitID), uint64(epoch), uint64(checkpointBlock))
+}

jsonrpc/bridge_endpoint_test.go

@@ -0,0 +1,40 @@
+package jsonrpc
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/hashicorp/go-hclog"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBridgeEndpoint(t *testing.T) {
+	store := newMockStore()
+
+	dispatcher := newDispatcher(
+		hclog.NewNullLogger(),
+		store,
+		&dispatcherParams{
+			chainID:                 0,
+			priceLimit:              0,
+			jsonRPCBatchLengthLimit: 20,
+			blockRangeLimit:         1000,
+		},
+	)
+
+	mockConnection, _ := newMockWsConnWithMsgCh()
+
+	msg := []byte(`{
+		"method": "bridge_generateExitProof",
+		"params": ["0x0001", "0x0001", "0x0002"],
+		"id": 1
+	}`)
+
+	data, err := dispatcher.HandleWs(msg, mockConnection)
+	require.NoError(t, err)
+
+	resp := new(SuccessResponse)
+	require.NoError(t, json.Unmarshal(data, resp))
+	require.Nil(t, resp.Error)
+	require.NotNil(t, resp.Result)
+}

jsonrpc/dispatcher.go

@@ -34,6 +34,7 @@ type endpoints struct {
 	Web3   *Web3
 	Net    *Net
 	TxPool *TxPool
+	Bridge *Bridge
 }
 
 // Dispatcher handles all json rpc requests by delegating
@@ -93,11 +94,13 @@ func (d *Dispatcher) registerEndpoints(store JSONRPCStore) {
 		d.params.chainName,
 	}
 	d.endpoints.TxPool = &TxPool{store}
+	d.endpoints.Bridge = &Bridge{store}
 
 	d.registerService("eth", d.endpoints.Eth)
 	d.registerService("net", d.endpoints.Net)
 	d.registerService("web3", d.endpoints.Web3)
 	d.registerService("txpool", d.endpoints.TxPool)
+	d.registerService("bridge", d.endpoints.Bridge)
 }
 
 func (d *Dispatcher) getFnHandler(req Request) (*serviceData, *funcData, Error) {

jsonrpc/jsonrpc.go

@@ -55,6 +55,7 @@ type JSONRPCStore interface {
 	networkStore
 	txPoolStore
 	filterManagerStore
+	bridgeStore
 }
 
 type Config struct {

jsonrpc/mocks_test.go

@@ -133,3 +133,9 @@ func (m *mockStore) GetTxs(inclQueued bool) (
 func (m *mockStore) GetCapacity() (uint64, uint64) {
 	return 0, 0
 }
+
+func (m *mockStore) GenerateExitProof(exitID, epoch, checkpointNumber uint64) ([]types.Hash, error) {
+	hash := types.BytesToHash([]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10})
+
+	return []types.Hash{hash}, nil
+}

server/server.go

@@ -446,6 +446,7 @@ type jsonRPCHub struct {
 	*state.Executor
 	*network.Server
 	consensus.Consensus
+	consensus.BridgeDataProvider
 }
 
 // HELPER + WRAPPER METHODS //
@@ -563,6 +564,7 @@ func (s *Server) setupJSONRPC() error {
 		Executor:           s.executor,
 		Consensus:          s.consensus,
 		Server:             s.network,
+		BridgeDataProvider: s.consensus.GetBridgeProvider(),
 	}
 
 	conf := &jsonrpc.Config{