Implement GetForkSchedule in the config API (#8345)

* span

* update ethereumapis

* implementation + tests

* typo

* fix variable shadowing

Co-authored-by: Raul Jordan <raul@prysmaticlabs.com>

beacon-chain/rpc/beaconv1/config.go

@@ -2,9 +2,9 @@ package beaconv1
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"reflect"
+	"sort"
 	"strconv"
 	"strings"
 
@@ -18,8 +18,37 @@ import (
 )
 
 // GetForkSchedule retrieve all scheduled upcoming forks this node is aware of.
-func (bs *Server) GetForkSchedule(ctx context.Context, req *ptypes.Empty) (*ethpb.ForkScheduleResponse, error) {
-	return nil, errors.New("unimplemented")
+func (bs *Server) GetForkSchedule(ctx context.Context, _ *ptypes.Empty) (*ethpb.ForkScheduleResponse, error) {
+	ctx, span := trace.StartSpan(ctx, "beaconv1.GetForkSchedule")
+	defer span.End()
+
+	schedule := params.BeaconConfig().ForkVersionSchedule
+	if len(schedule) == 0 {
+		return &ethpb.ForkScheduleResponse{
+			Data: make([]*ethpb.Fork, 0),
+		}, nil
+	}
+
+	epochs := sortedEpochs(schedule)
+	forks := make([]*ethpb.Fork, len(schedule))
+	var previous, current []byte
+	for i, e := range epochs {
+		if i == 0 {
+			previous = params.BeaconConfig().GenesisForkVersion
+		} else {
+			previous = current
+		}
+		current = schedule[e]
+		forks[i] = &ethpb.Fork{
+			PreviousVersion: previous,
+			CurrentVersion:  current,
+			Epoch:           e,
+		}
+	}
+
+	return &ethpb.ForkScheduleResponse{
+		Data: forks,
+	}, nil
 }
 
 // GetSpec retrieves specification configuration (without Phase 1 params) used on this node. Specification params list
@@ -38,7 +67,7 @@ func (bs *Server) GetSpec(ctx context.Context, _ *ptypes.Empty) (*ethpb.SpecResp
 }
 
 // GetDepositContract retrieves deposit contract address and genesis fork version.
-func (bs *Server) GetDepositContract(ctx context.Context, req *ptypes.Empty) (*ethpb.DepositContractResponse, error) {
+func (bs *Server) GetDepositContract(ctx context.Context, _ *ptypes.Empty) (*ethpb.DepositContractResponse, error) {
 	ctx, span := trace.StartSpan(ctx, "beaconv1.GetDepositContract")
 	defer span.End()
 
@@ -50,6 +79,17 @@ func (bs *Server) GetDepositContract(ctx context.Context, req *ptypes.Empty) (*e
 	}, nil
 }
 
+func sortedEpochs(forkSchedule map[uint64][]byte) []uint64 {
+	sortedEpochs := make([]uint64, len(forkSchedule))
+	i := 0
+	for k := range forkSchedule {
+		sortedEpochs[i] = k
+		i++
+	}
+	sort.Slice(sortedEpochs, func(a, b int) bool { return sortedEpochs[a] < sortedEpochs[b] })
+	return sortedEpochs
+}
+
 func prepareConfigSpec() (map[string]string, error) {
 	data := make(map[string]string)
 	config := *params.BeaconConfig()

beacon-chain/rpc/beaconv1/config_test.go

@@ -231,7 +231,6 @@ func TestGetDepositContract(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	config := params.BeaconConfig()
 	config.DepositChainID = chainId
-
 	config.DepositContractAddress = address
 	params.OverrideBeaconConfig(config)
 
@@ -241,3 +240,45 @@ func TestGetDepositContract(t *testing.T) {
 	assert.Equal(t, uint64(chainId), resp.Data.ChainId)
 	assert.Equal(t, address, resp.Data.Address)
 }
+
+func TestForkSchedule_Ok(t *testing.T) {
+	genesisForkVersion := []byte("Genesis")
+	firstForkVersion, firstForkEpoch := []byte("First"), uint64(100)
+	secondForkVersion, secondForkEpoch := []byte("Second"), uint64(200)
+	thirdForkVersion, thirdForkEpoch := []byte("Third"), uint64(300)
+
+	params.SetupTestConfigCleanup(t)
+	config := params.BeaconConfig()
+	config.GenesisForkVersion = genesisForkVersion
+	// Create fork schedule adding keys in non-sorted order.
+	schedule := make(map[uint64][]byte, 3)
+	schedule[secondForkEpoch] = secondForkVersion
+	schedule[firstForkEpoch] = firstForkVersion
+	schedule[thirdForkEpoch] = thirdForkVersion
+	config.ForkVersionSchedule = schedule
+	params.OverrideBeaconConfig(config)
+
+	s := &Server{}
+	resp, err := s.GetForkSchedule(context.Background(), &types.Empty{})
+	require.NoError(t, err)
+	require.Equal(t, 3, len(resp.Data))
+	fork := resp.Data[0]
+	assert.DeepEqual(t, genesisForkVersion, fork.PreviousVersion)
+	assert.DeepEqual(t, firstForkVersion, fork.CurrentVersion)
+	assert.Equal(t, firstForkEpoch, fork.Epoch)
+	fork = resp.Data[1]
+	assert.DeepEqual(t, firstForkVersion, fork.PreviousVersion)
+	assert.DeepEqual(t, secondForkVersion, fork.CurrentVersion)
+	assert.Equal(t, secondForkEpoch, fork.Epoch)
+	fork = resp.Data[2]
+	assert.DeepEqual(t, secondForkVersion, fork.PreviousVersion)
+	assert.DeepEqual(t, thirdForkVersion, fork.CurrentVersion)
+	assert.Equal(t, thirdForkEpoch, fork.Epoch)
+}
+
+func TestForkSchedule_NoForks(t *testing.T) {
+	s := &Server{}
+	resp, err := s.GetForkSchedule(context.Background(), &types.Empty{})
+	require.NoError(t, err)
+	assert.Equal(t, 0, len(resp.Data))
+}

deps.bzl

@@ -2573,8 +2573,8 @@ def prysm_deps():
         name = "com_github_prysmaticlabs_ethereumapis",
         build_file_generation = "off",
         importpath = "github.com/prysmaticlabs/ethereumapis",
-        sum = "h1:roqXwVG8cKjq6sOCbB+T5Kh+dYr1wpkk00c7/DdrqLg=",
-        version = "v0.0.0-20210115110118-c595a4e0c0a5",
+        sum = "h1:W8MMbOp3rkI972HrLaJDBgOzolv8K8S7SUf9reFtqtw=",
+        version = "v0.0.0-20210127105958-025470485ece",
     )
     go_repository(
         name = "com_github_prysmaticlabs_go_bitfield",

go.mod

@@ -84,7 +84,7 @@ require (
 	github.com/prometheus/client_golang v1.9.0
 	github.com/prometheus/procfs v0.3.0 // indirect
 	github.com/prometheus/tsdb v0.10.0 // indirect
-	github.com/prysmaticlabs/ethereumapis v0.0.0-20210115110118-c595a4e0c0a5
+	github.com/prysmaticlabs/ethereumapis v0.0.0-20210127105958-025470485ece
 	github.com/prysmaticlabs/go-bitfield v0.0.0-20210126073541-0bc6a2fd086d
 	github.com/prysmaticlabs/prombbolt v0.0.0-20210126082820-9b7adba6db7c
 	github.com/rs/cors v1.7.0

go.sum

@@ -1106,8 +1106,8 @@ github.com/prometheus/tsdb v0.10.0 h1:If5rVCMTp6W2SiRAQFlbpJNgVlgMEd+U2GZckwK38i
 github.com/prometheus/tsdb v0.10.0/go.mod h1:oi49uRhEe9dPUTlS3JRZOwJuVi6tmh10QSgwXEyGCt4=
 github.com/prysmaticlabs/bazel-go-ethereum v0.0.0-20201126065335-1fb46e307951 h1:Jncuyb/nIJgXbEe0iGz3MN5JmijPVGzwk3G5FR01phI=
 github.com/prysmaticlabs/bazel-go-ethereum v0.0.0-20201126065335-1fb46e307951/go.mod h1:JIfVb6esrqALTExdz9hRYvrP0xBDf6wCncIu1hNwHpM=
-github.com/prysmaticlabs/ethereumapis v0.0.0-20210115110118-c595a4e0c0a5 h1:roqXwVG8cKjq6sOCbB+T5Kh+dYr1wpkk00c7/DdrqLg=
-github.com/prysmaticlabs/ethereumapis v0.0.0-20210115110118-c595a4e0c0a5/go.mod h1:k7b2dxy6RppCG6kmOJkNOXzRpEoTdsPygc2aQhsUsZk=
+github.com/prysmaticlabs/ethereumapis v0.0.0-20210127105958-025470485ece h1:W8MMbOp3rkI972HrLaJDBgOzolv8K8S7SUf9reFtqtw=
+github.com/prysmaticlabs/ethereumapis v0.0.0-20210127105958-025470485ece/go.mod h1:k7b2dxy6RppCG6kmOJkNOXzRpEoTdsPygc2aQhsUsZk=
 github.com/prysmaticlabs/go-bitfield v0.0.0-20200322041314-62c2aee71669 h1:cX6YRZnZ9sgMqM5U14llxUiXVNJ3u07Res1IIjTOgtI=
 github.com/prysmaticlabs/go-bitfield v0.0.0-20200322041314-62c2aee71669/go.mod h1:hCwmef+4qXWjv0jLDbQdWnL0Ol7cS7/lCSS26WR+u6s=
 github.com/prysmaticlabs/go-bitfield v0.0.0-20210126073541-0bc6a2fd086d h1:zHsHj3qQc11cDBb4TdBKHamEAXT8P3yQVqlgMF/USjU=