Fix the periodic CI flow error in client

go.mod

@@ -22,7 +22,7 @@ require (
 	github.com/knative/build v0.6.0 // indirect
 	github.com/knative/pkg v0.0.0-20190518173526-34792a92cec2
 	github.com/knative/serving v0.6.0
-	github.com/knative/test-infra v0.0.0-20190531180034-a3c073a2fea1
+	github.com/knative/test-infra v0.0.0-20190624052103-517330119155
 	github.com/mattbaird/jsonpatch v0.0.0-20171005235357-81af80346b1a // indirect
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/modern-go/reflect2 v1.0.1 // indirect

go.sum

@@ -157,6 +157,8 @@ github.com/knative/test-infra v0.0.0-20190529123930-7d0c44fb03a9 h1:2kupVzyk+zet
 github.com/knative/test-infra v0.0.0-20190529123930-7d0c44fb03a9/go.mod h1:l77IWBscEV5T4sYb64/9iwRCVY4UXEIqMcAppsblHW4=
 github.com/knative/test-infra v0.0.0-20190531180034-a3c073a2fea1 h1:Y2QunZIzGuyvBNfWNpwK9/AAgu2P+Aa+k/3ykATGw30=
 github.com/knative/test-infra v0.0.0-20190531180034-a3c073a2fea1/go.mod h1:l77IWBscEV5T4sYb64/9iwRCVY4UXEIqMcAppsblHW4=
+github.com/knative/test-infra v0.0.0-20190624052103-517330119155 h1:ceTQvUNU19Vc13TlSNo6u0F0pHak9wcGJQ+gv0X4KlE=
+github.com/knative/test-infra v0.0.0-20190624052103-517330119155/go.mod h1:l77IWBscEV5T4sYb64/9iwRCVY4UXEIqMcAppsblHW4=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515/go.mod h1:+0opPa2QZZtGFBFZlji/RkVcI2GknAs/DXo4wKdlNEc=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=

test/e2e/e2e_flags.go

@@ -0,0 +1,31 @@
+/*
+Copyright 2019 The Knative Authors
+
+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
+
+    https://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 e2e
+
+import (
+	"flag"
+)
+
+var _ = initializeFlags()
+
+func initializeFlags() bool {
+	// emitmetrics is a required flag for running periodic test jobs, add it here as a no-op to avoid the error
+	emitMetrics := flag.Bool("emitmetrics", false,
+		"Set this flag to true if you would like tests to emit metrics, e.g. latency of resources being realized in the system.")
+	flag.Parse()
+	return *emitMetrics
+}