go/consensus: Add GetGenesisDocument

.changelog/2889.feature.2.md

@@ -0,0 +1,4 @@
+go/consensus: Add GetGenesisDocument
+
+The consensus client now has a new method to return the original
+genesis document.

go/consensus/api/api.go

@@ -80,6 +80,9 @@ type ClientBackend interface {
 	// WatchBlocks returns a channel that produces a stream of consensus
 	// blocks as they are being finalized.
 	WatchBlocks(ctx context.Context) (<-chan *Block, pubsub.ClosableSubscription, error)
+
+	// GetGenesisDocument returns the original genesis document.
+	GetGenesisDocument(ctx context.Context) (*genesis.Document, error)
 }
 
 // Block is a consensus block.

go/consensus/api/grpc.go

@@ -34,6 +34,8 @@ var (
 	methodGetBlock = serviceName.NewMethod("GetBlock", int64(0))
 	// methodGetTransactions is the GetTransactions method.
 	methodGetTransactions = serviceName.NewMethod("GetTransactions", int64(0))
+	// methodGetGenesisDocument is the GetGenesisDocument method.
+	methodGetGenesisDocument = serviceName.NewMethod("GetGenesisDocument", nil)
 
 	// methodWatchBlocks is the WatchBlocks method.
 	methodWatchBlocks = serviceName.NewMethod("WatchBlocks", nil)
@@ -82,6 +84,10 @@ var (
 				MethodName: methodGetTransactions.ShortName(),
 				Handler:    handlerGetTransactions,
 			},
+			{
+				MethodName: methodGetGenesisDocument.ShortName(),
+				Handler:    handlerGetGenesisDocument,
+			},
 		},
 		Streams: []grpc.StreamDesc{
 			{
@@ -297,6 +303,25 @@ func handlerGetTransactions( // nolint: golint
 	return interceptor(ctx, height, info, handler)
 }
 
+func handlerGetGenesisDocument( // nolint: golint
+	srv interface{},
+	ctx context.Context,
+	dec func(interface{}) error,
+	interceptor grpc.UnaryServerInterceptor,
+) (interface{}, error) {
+	if interceptor == nil {
+		return srv.(Backend).GetGenesisDocument(ctx)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: methodGetGenesisDocument.FullName(),
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(Backend).GetGenesisDocument(ctx)
+	}
+	return interceptor(ctx, nil, info, handler)
+}
+
 func handlerWatchBlocks(srv interface{}, stream grpc.ServerStream) error {
 	if err := stream.RecvMsg(nil); err != nil {
 		return err
@@ -498,6 +523,14 @@ func (c *consensusClient) GetTransactions(ctx context.Context, height int64) ([]
 	return rsp, nil
 }
 
+func (c *consensusClient) GetGenesisDocument(ctx context.Context) (*genesis.Document, error) {
+	var rsp genesis.Document
+	if err := c.conn.Invoke(ctx, methodGetGenesisDocument.FullName(), nil, &rsp); err != nil {
+		return nil, err
+	}
+	return &rsp, nil
+}
+
 func (c *consensusClient) WatchBlocks(ctx context.Context) (<-chan *Block, pubsub.ClosableSubscription, error) {
 	ctx, sub := pubsub.NewContextSubscription(ctx)
 

go/consensus/tendermint/epochtime/epochtime.go

@@ -125,7 +125,12 @@ func (t *tendermintBackend) updateCached(ctx context.Context, block *tmtypes.Blo
 // New constructs a new tendermint backed epochtime Backend instance,
 // with the specified epoch interval.
 func New(ctx context.Context, service service.TendermintService, interval int64) (api.Backend, error) {
-	base := service.GetGenesis().EpochTime.Base
+	genDoc, err := service.GetGenesisDocument(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	base := genDoc.EpochTime.Base
 	r := &tendermintBackend{
 		logger:   logging.GetLogger("epochtime/tendermint"),
 		service:  service,

go/consensus/tendermint/epochtime_mock/epochtime_mock.go

@@ -249,7 +249,12 @@ func New(ctx context.Context, service service.TendermintService) (api.SetableBac
 		}
 	})
 
-	if base := service.GetGenesis().EpochTime.Base; base != 0 {
+	genDoc, err := service.GetGenesisDocument(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	if base := genDoc.EpochTime.Base; base != 0 {
 		r.logger.Warn("ignoring non-zero base genesis epoch",
 			"base", base,
 		)

go/consensus/tendermint/service/service.go

@@ -12,7 +12,6 @@ import (
 	"github.com/oasislabs/oasis-core/go/common/service"
 	consensus "github.com/oasislabs/oasis-core/go/consensus/api"
 	"github.com/oasislabs/oasis-core/go/consensus/tendermint/abci"
-	genesis "github.com/oasislabs/oasis-core/go/genesis/api"
 )
 
 // TendermintService provides Tendermint access to Oasis core backends.
@@ -33,9 +32,6 @@ type TendermintService interface {
 	// ABCI multiplexer.
 	SetTransactionAuthHandler(abci.TransactionAuthHandler) error
 
-	// GetGenesis will return the oasis genesis document.
-	GetGenesis() *genesis.Document
-
 	// GetHeight returns the Tendermint block height.
 	GetHeight(ctx context.Context) (int64, error)
 

go/consensus/tendermint/tendermint.go

@@ -56,7 +56,6 @@ import (
 	tmstaking "github.com/oasislabs/oasis-core/go/consensus/tendermint/staking"
 	epochtimeAPI "github.com/oasislabs/oasis-core/go/epochtime/api"
 	genesisAPI "github.com/oasislabs/oasis-core/go/genesis/api"
-	"github.com/oasislabs/oasis-core/go/genesis/file"
 	keymanagerAPI "github.com/oasislabs/oasis-core/go/keymanager/api"
 	cmbackground "github.com/oasislabs/oasis-core/go/oasis-node/cmd/common/background"
 	cmflags "github.com/oasislabs/oasis-core/go/oasis-node/cmd/common/flags"
@@ -361,16 +360,9 @@ func (t *tendermintService) StateToGenesis(ctx context.Context, blockHeight int6
 	blockHeight = blk.Header.Height
 
 	// Get initial genesis doc.
-	genesisFileProvider, err := file.DefaultFileProvider()
+	genesisDoc, err := t.GetGenesisDocument(ctx)
 	if err != nil {
-		t.Logger.Error("failed getting genesis file provider",
-			"err", err,
-		)
-		return nil, err
-	}
-	genesisDoc, err := genesisFileProvider.GetGenesisDocument()
-	if err != nil {
-		t.Logger.Error("failed getting genesis document from file provider",
+		t.Logger.Error("failed getting genesis document",
 			"err", err,
 		)
 		return nil, err
@@ -449,6 +441,10 @@ func (t *tendermintService) StateToGenesis(ctx context.Context, blockHeight int6
 	}, nil
 }
 
+func (t *tendermintService) GetGenesisDocument(ctx context.Context) (*genesisAPI.Document, error) {
+	return t.genesis, nil
+}
+
 func (t *tendermintService) RegisterHaltHook(hook func(context.Context, int64, epochtimeAPI.EpochTime)) {
 	if !t.initialized() {
 		return
@@ -619,10 +615,6 @@ func (t *tendermintService) SetTransactionAuthHandler(handler abci.TransactionAu
 	return t.mux.SetTransactionAuthHandler(handler)
 }
 
-func (t *tendermintService) GetGenesis() *genesisAPI.Document {
-	return t.genesis
-}
-
 func (t *tendermintService) TransactionAuthHandler() consensusAPI.TransactionAuthHandler {
 	return t.mux.TransactionAuthHandler()
 }

go/consensus/tests/tester.go

@@ -28,6 +28,10 @@ func ConsensusImplementationTests(t *testing.T, backend consensus.ClientBackend)
 	ctx, cancel := context.WithTimeout(context.Background(), recvTimeout)
 	defer cancel()
 
+	genDoc, err := backend.GetGenesisDocument(ctx)
+	require.NoError(err, "GetGenesisDocument")
+	require.NotNil(genDoc, "returned genesis document should not be nil")
+
 	blk, err := backend.GetBlock(ctx, consensus.HeightLatest)
 	require.NoError(err, "GetBlock")
 	require.NotNil(blk, "returned block should not be nil")