prysm-pulse/shared/featureconfig/config.go

/*
Package featureconfig defines which features are enabled for runtime
in order to selctively enable certain features to maintain a stable runtime.

The process for implementing new features using this package is as follows:
	1. Add a new CMD flag in flags.go, and place it in the proper list(s) var for its client.
	2. Add a condition for the flag in the proper Configure function(s) below.
	3. Place any "new" behavior in the `if flagEnabled` statement.
	4. Place any "previous" behavior in the `else` statement.
	5. Ensure any tests using the new feature fail if the flag isn't enabled.
	5a. Use the following to enable your flag for tests:
	cfg := &featureconfig.Flag{
		VerifyAttestationSigs: true,
	}
	featureconfig.Init(cfg)
*/
package featureconfig

import (
	"github.com/sirupsen/logrus"
	"github.com/urfave/cli"
)

var log = logrus.WithField("prefix", "flags")

// Flag is a struct to represent what features the client will perform on runtime.
type Flag struct {
	GenesisDelay                  bool // GenesisDelay when processing a chain start genesis event.
	MinimalConfig                 bool // MinimalConfig as defined in the spec.
	WriteSSZStateTransitions      bool // WriteSSZStateTransitions to tmp directory.
	InitSyncNoVerify              bool // InitSyncNoVerify when initial syncing w/o verifying block's contents.
	SkipBLSVerify                 bool // Skips BLS verification across the runtime.
	EnableBackupWebhook           bool // EnableBackupWebhook to allow database backups to trigger from monitoring port /db/backup
	OptimizeProcessEpoch          bool // OptimizeProcessEpoch to process epoch with optimizations by pre computing records
	PruneFinalizedStates          bool // PruneFinalizedStates from the database.

	// Cache toggles.
	EnableAttestationCache   bool // EnableAttestationCache; see https://github.com/prysmaticlabs/prysm/issues/3106.
	EnableEth1DataVoteCache  bool // EnableEth1DataVoteCache; see https://github.com/prysmaticlabs/prysm/issues/3106.
	EnableNewCache           bool // EnableNewCache enables the node to use the new caching scheme.
	EnableBLSPubkeyCache     bool // EnableBLSPubkeyCache to improve wall time of PubkeyFromBytes.
	EnableShuffledIndexCache bool // EnableShuffledIndexCache to cache expensive shuffled index computation.
	EnableSkipSlotsCache     bool // EnableSkipSlotsCache caches the state in skipped slots.
}

var featureConfig *Flag

// Get retrieves feature config.
func Get() *Flag {
	if featureConfig == nil {
		return &Flag{}
	}
	return featureConfig
}

// Init sets the global config equal to the config that is passed in.
func Init(c *Flag) {
	featureConfig = c
}

// ConfigureBeaconChain sets the global config based
// on what flags are enabled for the beacon-chain client.
func ConfigureBeaconChain(ctx *cli.Context) {
	complainOnDeprecatedFlags(ctx)
	cfg := &Flag{}
	if ctx.GlobalBool(MinimalConfigFlag.Name) {
		log.Warn("Using minimal config")
		cfg.MinimalConfig = true
	}
	if ctx.GlobalBool(GenesisDelayFlag.Name) {
		log.Warn("Using non standard genesis delay. This may cause problems in a multi-node environment.")
		cfg.GenesisDelay = true
	}
	if ctx.GlobalBool(writeSSZStateTransitionsFlag.Name) {
		log.Warn("Writing SSZ states and blocks after state transitions")
		cfg.WriteSSZStateTransitions = true
	}
	if ctx.GlobalBool(EnableAttestationCacheFlag.Name) {
		log.Warn("Enabled unsafe attestation cache")
		cfg.EnableAttestationCache = true
	}
	if ctx.GlobalBool(EnableEth1DataVoteCacheFlag.Name) {
		log.Warn("Enabled unsafe eth1 data vote cache")
		cfg.EnableEth1DataVoteCache = true
	}
	if ctx.GlobalBool(InitSyncNoVerifyFlag.Name) {
		log.Warn("Initial syncing without verifying block's contents")
		cfg.InitSyncNoVerify = true
	}
	if ctx.GlobalBool(NewCacheFlag.Name) {
		log.Warn("Using new cache for committee shuffled indices")
		cfg.EnableNewCache = true
	}
	if ctx.GlobalBool(SkipBLSVerifyFlag.Name) {
		log.Warn("UNSAFE: Skipping BLS verification at runtime")
		cfg.SkipBLSVerify = true
	}
	if ctx.GlobalBool(enableBackupWebhookFlag.Name) {
		log.Warn("Allowing database backups to be triggered from HTTP webhook.")
		cfg.EnableBackupWebhook = true
	}
	if ctx.GlobalBool(enableBLSPubkeyCacheFlag.Name) {
		log.Warn("Enabled BLS pubkey cache.")
		cfg.EnableBLSPubkeyCache = true
	}
	if ctx.GlobalBool(OptimizeProcessEpoch.Name) {
		log.Warn("Processing epoch with optimizations")
		cfg.OptimizeProcessEpoch = true
	}
	if ctx.GlobalBool(pruneFinalizedStatesFlag.Name) {
		log.Warn("Enabled pruning old finalized states from database.")
		cfg.PruneFinalizedStates = true
	}
	if ctx.GlobalBool(enableShuffledIndexCache.Name) {
		log.Warn("Enabled shuffled index cache.")
		cfg.EnableShuffledIndexCache = true
	}
	if ctx.GlobalBool(enableSkipSlotsCache.Name) {
		log.Warn("Enabled skip slots cache.")
		cfg.EnableSkipSlotsCache = true
	}
	Init(cfg)
}

// ConfigureValidator sets the global config based
// on what flags are enabled for the validator client.
func ConfigureValidator(ctx *cli.Context) {
	complainOnDeprecatedFlags(ctx)
	cfg := &Flag{}
	if ctx.GlobalBool(MinimalConfigFlag.Name) {
		log.Warn("Using minimal config")
		cfg.MinimalConfig = true
	}
	Init(cfg)
}

func complainOnDeprecatedFlags(ctx *cli.Context) {
	for _, f := range deprecatedFlags {
		if ctx.IsSet(f.GetName()) {
			log.Errorf("%s is deprecated and has no effect. Do not use this flag, it will be deleted soon.", f.GetName())
		}
	}
}