Load chain config from file

beacon-chain/BUILD.bazel

@@ -19,6 +19,7 @@ go_library(
         "//shared/debug:go_default_library",
         "//shared/featureconfig:go_default_library",
         "//shared/logutil:go_default_library",
+        "//shared/params:go_default_library",
         "//shared/version:go_default_library",
         "@com_github_ethereum_go_ethereum//log:go_default_library",
         "@com_github_ipfs_go_log//:go_default_library",
@@ -28,6 +29,7 @@ go_library(
         "@com_github_x_cray_logrus_prefixed_formatter//:go_default_library",
         "@in_gopkg_urfave_cli_v2//:go_default_library",
         "@in_gopkg_urfave_cli_v2//altsrc:go_default_library",
+        "@in_gopkg_yaml_v2//:go_default_library",
         "@org_uber_go_automaxprocs//:go_default_library",
     ],
 )

beacon-chain/main.go

@@ -3,10 +3,13 @@ package main
 
 import (
 	"fmt"
+	"io/ioutil"
 	"os"
 	"runtime"
 	runtimeDebug "runtime/debug"
 
+	"gopkg.in/yaml.v2"
+
 	gethlog "github.com/ethereum/go-ethereum/log"
 	golog "github.com/ipfs/go-log"
 	joonix "github.com/joonix/log"
@@ -16,6 +19,7 @@ import (
 	"github.com/prysmaticlabs/prysm/shared/debug"
 	"github.com/prysmaticlabs/prysm/shared/featureconfig"
 	"github.com/prysmaticlabs/prysm/shared/logutil"
+	"github.com/prysmaticlabs/prysm/shared/params"
 	"github.com/prysmaticlabs/prysm/shared/version"
 	"github.com/sirupsen/logrus"
 	gologging "github.com/whyrusleeping/go-logging"
@@ -86,6 +90,7 @@ var appFlags = []cli.Flag{
 	cmd.LogFileName,
 	cmd.EnableUPnPFlag,
 	cmd.ConfigFileFlag,
+	cmd.ChainConfigFileFlag,
 }
 
 func init() {
@@ -141,7 +146,18 @@ func main() {
 				log.WithError(err).Error("Failed to configuring logging to disk.")
 			}
 		}
-
+		if ctx.IsSet(cmd.ChainConfigFileFlag.Name) {
+			chainConfigFileName := ctx.String(cmd.ChainConfigFileFlag.Name)
+			yamlFile, err := ioutil.ReadFile(chainConfigFileName)
+			if err != nil {
+				log.WithError(err).Error("Failed to read chain config file.")
+			}
+			conf := params.BeaconConfig()
+			if err := yaml.Unmarshal(yamlFile, conf); err != nil {
+				log.WithError(err).Error("Failed to parse chain config yaml file.")
+			}
+			params.OverrideBeaconConfig(conf)
+		}
 		if ctx.IsSet(flags.SetGCPercent.Name) {
 			runtimeDebug.SetGCPercent(ctx.Int(flags.SetGCPercent.Name))
 		}

beacon-chain/usage.go

@@ -61,6 +61,7 @@ var appHelpFlagGroups = []flagGroup{
 			cmd.ForceClearDB,
 			cmd.ClearDB,
 			cmd.ConfigFileFlag,
+			cmd.ChainConfigFileFlag,
 		},
 	},
 	{

shared/cmd/flags.go

@@ -171,7 +171,12 @@ var (
 	}
 	// ConfigFileFlag specifies the filepath to load flag values.
 	ConfigFileFlag = &cli.StringFlag{
-		Name:  "config-file",
+		Name:  "flag-config-file",
 		Usage: "The filepath to a yaml file with flag values",
 	}
+	// ChainConfigFileFlag specifies the filepath to load flag values.
+	ChainConfigFileFlag = &cli.StringFlag{
+		Name:  "chain-config-file",
+		Usage: "The filepath to a yaml file with chain config values",
+	}
 )

shared/params/config.go

@@ -16,9 +16,9 @@ type BeaconChainConfig struct {
 	MinGenesisDelay          uint64 `yaml:"MIN_GENESIS_DELAY"`           // Minimum number of seconds to delay starting the ETH2 genesis. Must be at least 1 second.
 
 	// Misc constants.
-	TargetCommitteeSize            uint64 `yaml:"TARGET_COMMITTEE_SIZE"`        // TargetCommitteeSize is the number of validators in a committee when the chain is healthy.
-	MaxValidatorsPerCommittee      uint64 `yaml:"MAX_VALIDATORS_PER_COMMITTEE"` // MaxValidatorsPerCommittee defines the upper bound of the size of a committee.
-	MaxCommitteesPerSlot           uint64 // MaxCommitteesPerSlot defines the max amount of committee in a single slot.
+	TargetCommitteeSize            uint64 `yaml:"TARGET_COMMITTEE_SIZE"`              // TargetCommitteeSize is the number of validators in a committee when the chain is healthy.
+	MaxValidatorsPerCommittee      uint64 `yaml:"MAX_VALIDATORS_PER_COMMITTEE"`       // MaxValidatorsPerCommittee defines the upper bound of the size of a committee.
+	MaxCommitteesPerSlot           uint64 `yaml:"MAX_COMMITTEES_PER_SLOT"`            // MaxCommitteesPerSlot defines the max amount of committee in a single slot.
 	MinPerEpochChurnLimit          uint64 `yaml:"MIN_PER_EPOCH_CHURN_LIMIT"`          // MinPerEpochChurnLimit is the minimum amount of churn allotted for validator rotations.
 	ChurnLimitQuotient             uint64 `yaml:"CHURN_LIMIT_QUOTIENT"`               // ChurnLimitQuotient is used to determine the limit of how many validators can rotate per epoch.
 	ShuffleRoundCount              uint64 `yaml:"SHUFFLE_ROUND_COUNT"`                // ShuffleRoundCount is used for retrieving the permuted index.