Countdown Until Genesis (#6231)

* added in logic
* latest countdown
* fixed up formatting and add tests
* ready for review
* Merge branch 'master' into countdown-genesis
* no log if after genesis
* Merge branch 'countdown-genesis' of github.com:prysmaticlabs/prysm into countdown-genesis
* countdown
* smarter logging
* added buffer period for countdown
* Merge refs/heads/master into countdown-genesis

shared/params/config.go

@@ -100,6 +100,7 @@ type BeaconChainConfig struct {
 	DefaultPageSize           int           // DefaultPageSize defines the default page size for RPC server request.
 	MaxPeersToSync            int           // MaxPeersToSync describes the limit for number of peers in round robin sync.
 	SlotsPerArchivedPoint     uint64        // SlotsPerArchivedPoint defines the number of slots per one archived point.
+	GenesisCountdownInterval  time.Duration // How often to log the countdown until the genesis time is reached.
 
 	// Slasher constants.
 	WeakSubjectivityPeriod    uint64 // WeakSubjectivityPeriod defines the time period expressed in number of epochs were proof of stake network should validate block headers and attestations for slashable events.
@@ -200,6 +201,7 @@ var defaultBeaconConfig = &BeaconChainConfig{
 	DefaultPageSize:           250,
 	MaxPeersToSync:            15,
 	SlotsPerArchivedPoint:     2048,
+	GenesisCountdownInterval:  time.Minute,
 
 	// Slasher related values.
 	WeakSubjectivityPeriod:    54000,

shared/slotutil/BUILD.bazel

@@ -4,6 +4,7 @@ load("@io_bazel_rules_go//go:def.bzl", "go_test")
 go_library(
     name = "go_default_library",
     srcs = [
+        "countdown.go",
         "slotticker.go",
         "slottime.go",
     ],
@@ -12,12 +13,22 @@ go_library(
     deps = [
         "//shared/params:go_default_library",
         "//shared/roughtime:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
     ],
 )
 
 go_test(
     name = "go_default_test",
     size = "small",
-    srcs = ["slotticker_test.go"],
+    srcs = [
+        "countdown_test.go",
+        "slotticker_test.go",
+    ],
     embed = [":go_default_library"],
+    deps = [
+        "//shared/params:go_default_library",
+        "//shared/roughtime:go_default_library",
+        "//shared/testutil:go_default_library",
+        "@com_github_sirupsen_logrus//hooks/test:go_default_library",
+    ],
 )

shared/slotutil/countdown.go

@@ -0,0 +1,51 @@
+package slotutil
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/prysmaticlabs/prysm/shared/params"
+	"github.com/prysmaticlabs/prysm/shared/roughtime"
+	"github.com/sirupsen/logrus"
+)
+
+var log = logrus.WithField("prefix", "slotutil")
+
+// CountdownToGenesis starts a ticker at the specified duration
+// logging the remaining minutes until the genesis chainstart event
+// along with important genesis state metadata such as number
+// of genesis validators.
+func CountdownToGenesis(ctx context.Context, genesisTime time.Time, genesisValidatorCount uint64) {
+	ticker := time.NewTicker(params.BeaconConfig().GenesisCountdownInterval)
+	timeTillGenesis := genesisTime.Sub(roughtime.Now())
+	logFields := logrus.Fields{
+		"genesisValidators": fmt.Sprintf("%d", genesisValidatorCount),
+		"genesisTime":       fmt.Sprintf("%v", genesisTime),
+	}
+	for {
+		select {
+		case <-time.After(timeTillGenesis):
+			log.WithFields(logFields).Info("Chain genesis time reached")
+			return
+		case <-ticker.C:
+			currentTime := roughtime.Now()
+			if currentTime.After(genesisTime) {
+				log.WithFields(logFields).Info("Chain genesis time reached")
+				return
+			}
+			timeRemaining := genesisTime.Sub(currentTime)
+			if timeRemaining <= 2*time.Minute {
+				ticker = time.NewTicker(time.Second)
+			}
+			if timeRemaining >= time.Second {
+				log.WithFields(logFields).Infof(
+					"%s until chain genesis",
+					timeRemaining.Truncate(time.Second),
+				)
+			}
+		case <-ctx.Done():
+			return
+		}
+	}
+}

shared/slotutil/countdown_test.go

@@ -0,0 +1,30 @@
+package slotutil
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/prysmaticlabs/prysm/shared/params"
+	"github.com/prysmaticlabs/prysm/shared/roughtime"
+	"github.com/prysmaticlabs/prysm/shared/testutil"
+	logTest "github.com/sirupsen/logrus/hooks/test"
+)
+
+func TestCountdownToGenesis(t *testing.T) {
+	hook := logTest.NewGlobal()
+	params.SetupTestConfigCleanup(t)
+	config := params.BeaconConfig()
+	config.GenesisCountdownInterval = time.Millisecond * 500
+	params.OverrideBeaconConfig(config)
+
+	firstStringResult := "1s until chain genesis"
+	genesisReached := "Chain genesis time reached"
+	CountdownToGenesis(
+		context.Background(),
+		roughtime.Now().Add(2*time.Second),
+		params.BeaconConfig().MinGenesisActiveValidatorCount,
+	)
+	testutil.AssertLogsContain(t, hook, firstStringResult)
+	testutil.AssertLogsContain(t, hook, genesisReached)
+}