Grandpa Prove Finality RPC (#1379)

chain/gssmr/config.toml

@@ -33,5 +33,5 @@ nomdns = false
 enabled = false
 port = 8545
 host = "localhost"
-modules = ["system", "author", "chain", "state", "rpc"]
+modules = ["system", "author", "chain", "state", "rpc", "grandpa"]
 ws-port = 8546

chain/gssmr/defaults.go

@@ -79,7 +79,7 @@ var (
 	// DefaultRPCHTTPPort rpc port
 	DefaultRPCHTTPPort = uint32(8545)
 	// DefaultRPCModules rpc modules
-	DefaultRPCModules = []string{"system", "author", "chain", "state", "rpc"}
+	DefaultRPCModules = []string{"system", "author", "chain", "state", "rpc", "grandpa"}
 	// DefaultRPCWSPort rpc websocket port
 	DefaultRPCWSPort = uint32(8546)
 )

chain/ksmcc/config.toml

@@ -34,7 +34,7 @@ enabled = false
 external = false
 port = 8545
 host = "localhost"
-modules = ["system", "author", "chain", "state", "rpc"]
+modules = ["system", "author", "chain", "state", "rpc", "grandpa"]
 ws-port = 8546
 ws = false
 ws-external = false

chain/ksmcc/defaults.go

@@ -75,7 +75,7 @@ var (
 	// DefaultRPCHTTPPort rpc port
 	DefaultRPCHTTPPort = uint32(8545)
 	// DefaultRPCModules rpc modules
-	DefaultRPCModules = []string{"system", "author", "chain", "state", "rpc"}
+	DefaultRPCModules = []string{"system", "author", "chain", "state", "rpc", "grandpa"}
 	// DefaultRPCWSPort rpc websocket port
 	DefaultRPCWSPort = uint32(8546)
 )

chain/polkadot/config.toml

@@ -33,5 +33,5 @@ nomdns = false
 enabled = false
 port = 8545
 host = "localhost"
-modules = ["system", "author", "chain", "state", "rpc"]
+modules = ["system", "author", "chain", "state", "rpc", "grandpa"]
 ws-port = 8546

chain/polkadot/defaults.go

@@ -79,7 +79,7 @@ var (
 	// DefaultRPCHTTPPort rpc port
 	DefaultRPCHTTPPort = uint32(8545)
 	// DefaultRPCModules rpc modules
-	DefaultRPCModules = []string{"system", "author", "chain", "state", "rpc"}
+	DefaultRPCModules = []string{"system", "author", "chain", "state", "rpc", "grandpa"}
 	// DefaultRPCWSPort rpc websocket port
 	DefaultRPCWSPort = uint32(8546)
 )

dot/rpc/http.go

@@ -109,6 +109,8 @@ func (h *HTTPServer) RegisterModules(mods []string) {
 			srvc = modules.NewAuthorModule(h.logger, h.serverConfig.CoreAPI, h.serverConfig.RuntimeAPI, h.serverConfig.TransactionQueueAPI)
 		case "chain":
 			srvc = modules.NewChainModule(h.serverConfig.BlockAPI)
+		case "grandpa":
+			srvc = modules.NewGrandpaModule(h.serverConfig.BlockAPI)
 		case "state":
 			srvc = modules.NewStateModule(h.serverConfig.NetworkAPI, h.serverConfig.StorageAPI, h.serverConfig.CoreAPI)
 		case "rpc":

dot/rpc/modules/api.go

@@ -29,10 +29,13 @@ type BlockAPI interface {
 	GetBlockByHash(hash common.Hash) (*types.Block, error)
 	GetBlockHash(blockNumber *big.Int) (*common.Hash, error)
 	GetFinalizedHash(uint64, uint64) (common.Hash, error)
+	HasJustification(hash common.Hash) (bool, error)
+	GetJustification(hash common.Hash) ([]byte, error)
 	RegisterImportedChannel(ch chan<- *types.Block) (byte, error)
 	UnregisterImportedChannel(id byte)
 	RegisterFinalizedChannel(ch chan<- *types.Header) (byte, error)
 	UnregisterFinalizedChannel(id byte)
+	SubChain(start, end common.Hash) ([]common.Hash, error)
 }
 
 // NetworkAPI interface for network state methods

dot/rpc/modules/dev.go

@@ -13,6 +13,7 @@
 //
 // You should have received a copy of the GNU Lesser General Public License
 // along with the gossamer library. If not, see <http://www.gnu.org/licenses/>.
+
 package modules
 
 import (

dot/rpc/modules/errors.go

@@ -13,6 +13,7 @@
 //
 // You should have received a copy of the GNU Lesser General Public License
 // along with the gossamer library. If not, see <http://www.gnu.org/licenses/>.
+
 package modules
 
 import "errors"

dot/rpc/modules/grandpa.go

@@ -0,0 +1,73 @@
+// Copyright 2020 ChainSafe Systems (ON) Corp.
+// This file is part of gossamer.
+//
+// The gossamer library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The gossamer library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the gossamer library. If not, see <http://www.gnu.org/licenses/>.
+
+package modules
+
+import (
+	"net/http"
+
+	"github.com/ChainSafe/gossamer/lib/common"
+)
+
+// GrandpaModule init parameters
+type GrandpaModule struct {
+	blockAPI BlockAPI
+}
+
+// NewGrandpaModule creates a new Grandpa rpc module.
+func NewGrandpaModule(api BlockAPI) *GrandpaModule {
+	return &GrandpaModule{
+		blockAPI: api,
+	}
+}
+
+// ProveFinalityRequest request struct
+type ProveFinalityRequest struct {
+	blockHashStart common.Hash
+	blockHashEnd   common.Hash
+	authorityID    uint64
+}
+
+// ProveFinalityResponse is an optional SCALE encoded proof array
+type ProveFinalityResponse [][]byte
+
+// ProveFinality for the provided block range. Returns NULL if there are no known finalized blocks in the range. If no authorities set is provided, the current one will be attempted.
+func (gm *GrandpaModule) ProveFinality(r *http.Request, req *ProveFinalityRequest, res *ProveFinalityResponse) error {
+	blocksToCheck, err := gm.blockAPI.SubChain(req.blockHashStart, req.blockHashEnd)
+	if err != nil {
+		return err
+	}
+
+	// Leaving check in for linter
+	if req.authorityID != uint64(0) {
+		// TODO: #1404 Check if functionality relevant
+	}
+
+	for _, block := range blocksToCheck {
+		hasJustification, _ := gm.blockAPI.HasJustification(block)
+		if !hasJustification {
+			continue
+		}
+
+		justification, err := gm.blockAPI.GetJustification(block)
+		if err != nil {
+			continue
+		}
+		*res = append(*res, justification)
+	}
+
+	return nil
+}

dot/rpc/modules/grandpa_test.go

@@ -0,0 +1,57 @@
+// Copyright 2020 ChainSafe Systems (ON) Corp.
+// This file is part of gossamer.
+//
+// The gossamer library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The gossamer library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the gossamer library. If not, see <http://www.gnu.org/licenses/>.
+
+package modules
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/ChainSafe/gossamer/dot/state"
+)
+
+func TestGrandpaProveFinality(t *testing.T) {
+	testStateService := newTestStateService(t)
+
+	state.AddBlocksToState(t, testStateService.Block, 3)
+	bestBlock, err := testStateService.Block.BestBlock()
+
+	if err != nil {
+		t.Errorf("Fail: bestblock failed")
+	}
+
+	gmSvc := NewGrandpaModule(testStateService.Block)
+
+	testStateService.Block.SetJustification(bestBlock.Header.ParentHash, make([]byte, 10))
+	testStateService.Block.SetJustification(bestBlock.Header.Hash(), make([]byte, 11))
+
+	var expectedResponse ProveFinalityResponse
+	expectedResponse = append(expectedResponse, make([]byte, 10), make([]byte, 11))
+
+	res := new(ProveFinalityResponse)
+	err = gmSvc.ProveFinality(nil, &ProveFinalityRequest{
+		blockHashStart: bestBlock.Header.ParentHash,
+		blockHashEnd:   bestBlock.Header.Hash(),
+	}, res)
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(*res, expectedResponse) {
+		t.Errorf("Fail: expected: %+v got: %+v\n", res, &expectedResponse)
+	}
+}

dot/rpc/modules/rpc.go

@@ -13,6 +13,7 @@
 //
 // You should have received a copy of the GNU Lesser General Public License
 // along with the gossamer library. If not, see <http://www.gnu.org/licenses/>.
+
 package modules
 
 import "net/http"

dot/rpc/websocket_test.go

@@ -120,6 +120,18 @@ func (m *MockBlockAPI) RegisterFinalizedChannel(ch chan<- *types.Header) (byte,
 }
 func (m *MockBlockAPI) UnregisterFinalizedChannel(id byte) {}
 
+func (m *MockBlockAPI) GetJustification(hash common.Hash) ([]byte, error) {
+	return make([]byte, 10), nil
+}
+
+func (m *MockBlockAPI) HasJustification(hash common.Hash) (bool, error) {
+	return true, nil
+}
+
+func (m *MockBlockAPI) SubChain(start, end common.Hash) ([]common.Hash, error) {
+	return make([]common.Hash, 0), nil
+}
+
 type MockStorageAPI struct{}
 
 func (m *MockStorageAPI) GetStorage(_ *common.Hash, key []byte) ([]byte, error) {

tests/utils/rpc_methods.go

@@ -33,4 +33,7 @@ var (
 
 	// DEV METHODS
 	DevControl = "dev_control"
+
+	// GRANDPA
+	GrandpaProveFinality = "grandpa_proveFinality"
 )