Remove Shutdown{Kill,Stop}Timeout fields from WFE (#2062)

This PR removes the Shutdown{Kill,Stop}Timeout fields from `cmd/boulder-wfe/main.go`. These fields are set in `main.go` but never used. The relevant config fields only need to be used when creating an `httpdown.HTTP` in `cmd/boulder-wfe/main.go`.

Existing duration parsing was replaced with `cmd.ConfigDuration` use.

cmd/boulder-wfe/main.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"net/http"
 	"os"
-	"time"
 
 	"github.com/facebookgo/httpdown"
 	"github.com/jmhodges/clock"
@@ -27,13 +26,13 @@ type config struct {
 
 		AllowOrigins []string
 
-		CertCacheDuration           string
-		CertNoCacheExpirationWindow string
-		IndexCacheDuration          string
-		IssuerCacheDuration         string
+		CertCacheDuration           cmd.ConfigDuration
+		CertNoCacheExpirationWindow cmd.ConfigDuration
+		IndexCacheDuration          cmd.ConfigDuration
+		IssuerCacheDuration         cmd.ConfigDuration
 
-		ShutdownStopTimeout string
-		ShutdownKillTimeout string
+		ShutdownStopTimeout cmd.ConfigDuration
+		ShutdownKillTimeout cmd.ConfigDuration
 
 		SubscriberAgreementURL string
 
@@ -99,19 +98,10 @@ func main() {
 	wfe.AllowOrigins = c.WFE.AllowOrigins
 	wfe.CheckMalformedCSR = c.WFE.CheckMalformedCSR
 
-	wfe.CertCacheDuration, err = time.ParseDuration(c.WFE.CertCacheDuration)
-	cmd.FailOnError(err, "Couldn't parse certificate caching duration")
-	wfe.CertNoCacheExpirationWindow, err = time.ParseDuration(c.WFE.CertNoCacheExpirationWindow)
-	cmd.FailOnError(err, "Couldn't parse certificate expiration no-cache window")
-	wfe.IndexCacheDuration, err = time.ParseDuration(c.WFE.IndexCacheDuration)
-	cmd.FailOnError(err, "Couldn't parse index caching duration")
-	wfe.IssuerCacheDuration, err = time.ParseDuration(c.WFE.IssuerCacheDuration)
-	cmd.FailOnError(err, "Couldn't parse issuer caching duration")
-
-	wfe.ShutdownStopTimeout, err = time.ParseDuration(c.WFE.ShutdownStopTimeout)
-	cmd.FailOnError(err, "Couldn't parse shutdown stop timeout")
-	wfe.ShutdownKillTimeout, err = time.ParseDuration(c.WFE.ShutdownKillTimeout)
-	cmd.FailOnError(err, "Couldn't parse shutdown kill timeout")
+	wfe.CertCacheDuration = c.WFE.CertCacheDuration.Duration
+	wfe.CertNoCacheExpirationWindow = c.WFE.CertNoCacheExpirationWindow.Duration
+	wfe.IndexCacheDuration = c.WFE.IndexCacheDuration.Duration
+	wfe.IssuerCacheDuration = c.WFE.IssuerCacheDuration.Duration
 
 	wfe.IssuerCert, err = cmd.LoadCert(c.Common.IssuerCert)
 	cmd.FailOnError(err, fmt.Sprintf("Couldn't read issuer cert [%s]", c.Common.IssuerCert))
@@ -134,8 +124,8 @@ func main() {
 	}
 
 	hd := &httpdown.HTTP{
-		StopTimeout: wfe.ShutdownStopTimeout,
-		KillTimeout: wfe.ShutdownKillTimeout,
+		StopTimeout: c.WFE.ShutdownStopTimeout.Duration,
+		KillTimeout: c.WFE.ShutdownKillTimeout.Duration,
 		Stats:       metrics.NewFBAdapter(stats, "WFE", clock.Default()),
 	}
 	err = httpdown.ListenAndServe(srv, hd)

wfe/wfe.go

@@ -80,10 +80,6 @@ type WebFrontEndImpl struct {
 	// Maximum duration of a request
 	RequestTimeout time.Duration
 
-	// Graceful shutdown settings
-	ShutdownStopTimeout time.Duration
-	ShutdownKillTimeout time.Duration
-
 	// Feature gates
 	CheckMalformedCSR bool
 }