From b61eaefb0d8a27f6bae1802f418818a51cddcbde Mon Sep 17 00:00:00 2001
From: Jim McDonald <Jim@mcdee.net>
Date: Thu, 12 Mar 2020 15:32:01 +0000
Subject: [PATCH] Add chain status

---
 cmd/chaininfo.go    |  9 ++----
 cmd/chainstatus.go  | 72 +++++++++++++++++++++++++++++++++++++++++++++
 cmd/version.go      |  2 +-
 grpc/beaconchain.go |  9 ++++++
 4 files changed, 85 insertions(+), 7 deletions(-)
 create mode 100644 cmd/chainstatus.go

diff --git a/cmd/chaininfo.go b/cmd/chaininfo.go
index f6a4b66..b0e9bf0 100644
--- a/cmd/chaininfo.go
+++ b/cmd/chaininfo.go
@@ -43,13 +43,10 @@ In quiet mode this will return 0 if the chain information can be obtained, other
 			os.Exit(_exit_success)
 		}
 
-		for k, v := range config {
-			fmt.Printf("%v => %v\n", k, v)
-		}
 		fmt.Printf("Genesis time:\t\t%s\n", genesisTime.Format(time.UnixDate))
 		slot := timestampToSlot(genesisTime.Unix(), time.Now().Unix(), config["SecondsPerSlot"].(uint64))
 		fmt.Printf("Current slot:\t\t%d\n", slot)
-		fmt.Printf("Current epoch:\t\t%d\n", slot/int64(config["SlotsPerEpoch"].(uint64)))
+		fmt.Printf("Current epoch:\t\t%d\n", slot/config["SlotsPerEpoch"].(uint64))
 		outputIf(verbose, fmt.Sprintf("Genesis fork version:\t%0x", config["GenesisForkVersion"].([]byte)))
 		outputIf(verbose, fmt.Sprintf("Genesis timestamp:\t%v", genesisTime.Unix()))
 		outputIf(verbose, fmt.Sprintf("Seconds per slot:\t%v", config["SecondsPerSlot"].(uint64)))
@@ -64,9 +61,9 @@ func init() {
 	chainFlags(chainInfoCmd)
 }
 
-func timestampToSlot(genesis int64, timestamp int64, secondsPerSlot uint64) int64 {
+func timestampToSlot(genesis int64, timestamp int64, secondsPerSlot uint64) uint64 {
 	if timestamp < genesis {
 		return 0
 	}
-	return (timestamp - genesis) / int64(secondsPerSlot)
+	return uint64(timestamp-genesis) / secondsPerSlot
 }
diff --git a/cmd/chainstatus.go b/cmd/chainstatus.go
new file mode 100644
index 0000000..ae0f166
--- /dev/null
+++ b/cmd/chainstatus.go
@@ -0,0 +1,72 @@
+// Copyright © 2020 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/spf13/cobra"
+	"github.com/wealdtech/ethdo/grpc"
+)
+
+var chainStatusCmd = &cobra.Command{
+	Use:   "status",
+	Short: "Obtain status about a chain",
+	Long: `Obtain status about a chain.  For example:
+
+    ethdo chain status
+
+In quiet mode this will return 0 if the chain status can be obtained, otherwise 1.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		err := connect()
+		errCheck(err, "Failed to obtain connection to Ethereum 2 beacon chain node")
+		config, err := grpc.FetchChainConfig(eth2GRPCConn)
+		errCheck(err, "Failed to obtain beacon chain configuration")
+
+		genesisTime, err := grpc.FetchGenesis(eth2GRPCConn)
+		errCheck(err, "Failed to obtain genesis time")
+
+		info, err := grpc.FetchChainInfo(eth2GRPCConn)
+		errCheck(err, "Failed to obtain chain info")
+
+		if quiet {
+			os.Exit(_exit_success)
+		}
+
+		slot := timestampToSlot(genesisTime.Unix(), time.Now().Unix(), config["SecondsPerSlot"].(uint64))
+		fmt.Printf("Current slot:\t\t%d\n", slot)
+		fmt.Printf("Finalized slot:\t\t%d", info.GetFinalizedSlot())
+		if verbose {
+			distance := slot - info.GetFinalizedSlot()
+			fmt.Printf(" (%d)", distance)
+		}
+		fmt.Printf("\n")
+		fmt.Printf("Justified slot:\t\t%d", info.GetJustifiedSlot())
+		if verbose {
+			distance := slot - info.GetJustifiedSlot()
+			fmt.Printf(" (%d)", distance)
+		}
+		fmt.Printf("\n")
+		outputIf(verbose, fmt.Sprintf("Prior justified slot:\t%v (%d)", info.GetPreviousJustifiedSlot(), slot-info.GetPreviousJustifiedSlot()))
+
+		os.Exit(_exit_success)
+	},
+}
+
+func init() {
+	chainCmd.AddCommand(chainStatusCmd)
+	chainFlags(chainStatusCmd)
+}
diff --git a/cmd/version.go b/cmd/version.go
index 04df02d..f1fedb5 100644
--- a/cmd/version.go
+++ b/cmd/version.go
@@ -30,7 +30,7 @@ var versionCmd = &cobra.Command{
 
     ethdo version.`,
 	Run: func(cmd *cobra.Command, args []string) {
-		fmt.Println("1.2.3")
+		fmt.Println("1.2.4")
 		if viper.GetBool("verbose") {
 			buildInfo, ok := dbg.ReadBuildInfo()
 			if ok {
diff --git a/grpc/beaconchain.go b/grpc/beaconchain.go
index 54375c1..8a011c1 100644
--- a/grpc/beaconchain.go
+++ b/grpc/beaconchain.go
@@ -107,3 +107,12 @@ func FetchValidatorInfo(conn *grpc.ClientConn, account wtypes.Account) (*ethpb.V
 	}
 	return stream.Recv()
 }
+
+// FetchChainInfo fetches current chain info from the beacon node.
+func FetchChainInfo(conn *grpc.ClientConn) (*ethpb.ChainHead, error) {
+	beaconClient := ethpb.NewBeaconChainClient(conn)
+	ctx, cancel := context.WithTimeout(context.Background(), viper.GetDuration("timeout"))
+	defer cancel()
+
+	return beaconClient.GetChainHead(ctx, &empty.Empty{})
+}