From 051de9a2379e7864157455cac96e78cc1b6f2857 Mon Sep 17 00:00:00 2001
From: Andrew Bayer <andrew.bayer@gmail.com>
Date: Tue, 5 Mar 2019 08:28:22 -0500
Subject: [PATCH] Container names must end with an alphanumeric character

---
 pkg/names/generate.go                         |  7 +++-
 .../v1alpha1/taskrun/resources/pod_test.go    | 36 +++++++++++++++++--
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/pkg/names/generate.go b/pkg/names/generate.go
index 6c21714f2ea..ef3b27e134e 100644
--- a/pkg/names/generate.go
+++ b/pkg/names/generate.go
@@ -18,8 +18,8 @@ package names
 
 import (
 	"fmt"
-
 	utilrand "k8s.io/apimachinery/pkg/util/rand"
+	"regexp"
 )
 
 // NameGenerator generates names for objects. Some backends may have more information
@@ -61,5 +61,10 @@ func (simpleNameGenerator) RestrictLength(base string) string {
 	if len(base) > maxNameLength {
 		base = base[:maxNameLength]
 	}
+	var isAlphaNumeric = regexp.MustCompile(`^[a-zA-Z0-9]+$`).MatchString
+
+	for !isAlphaNumeric(base[len(base)-1:]) {
+		base = base[:len(base)-1]
+	}
 	return base
 }
diff --git a/pkg/reconciler/v1alpha1/taskrun/resources/pod_test.go b/pkg/reconciler/v1alpha1/taskrun/resources/pod_test.go
index 2cb19606355..99657af8899 100644
--- a/pkg/reconciler/v1alpha1/taskrun/resources/pod_test.go
+++ b/pkg/reconciler/v1alpha1/taskrun/resources/pod_test.go
@@ -185,7 +185,7 @@ func TestMakePod(t *testing.T) {
 		desc: "very-long-step-name",
 		b: v1alpha1.BuildSpec{
 			Steps: []corev1.Container{{
-				Name:  "a-sixty-three-character-step-name-to-trigger-max-length-checkxx",
+				Name:  "a-very-long-character-step-name-to-trigger-max-len----and-invalid-characters",
 				Image: "image",
 			}},
 		},
@@ -203,7 +203,39 @@ func TestMakePod(t *testing.T) {
 				WorkingDir:   workspaceDir,
 			}},
 			Containers: []corev1.Container{{
-				Name:         "build-step-a-sixty-three-character-step-name-to-trigger-max-len",
+				Name:         "build-step-a-very-long-character-step-name-to-trigger-max-len",
+				Image:        "image",
+				Env:          implicitEnvVars,
+				VolumeMounts: implicitVolumeMounts,
+				WorkingDir:   workspaceDir,
+			},
+				nopContainer,
+			},
+			Volumes: implicitVolumes,
+		},
+	}, {
+		desc: "step-name-ends-with-non-alphanumeric",
+		b: v1alpha1.BuildSpec{
+			Steps: []corev1.Container{{
+				Name:  "ends-with-invalid-%%__$$",
+				Image: "image",
+			}},
+		},
+		bAnnotations: map[string]string{
+			"simple-annotation-key": "simple-annotation-val",
+		},
+		want: &corev1.PodSpec{
+			RestartPolicy: corev1.RestartPolicyNever,
+			InitContainers: []corev1.Container{{
+				Name:         containerPrefix + credsInit + "-9l9zj",
+				Image:        *credsImage,
+				Args:         []string{},
+				Env:          implicitEnvVars,
+				VolumeMounts: implicitVolumeMounts,
+				WorkingDir:   workspaceDir,
+			}},
+			Containers: []corev1.Container{{
+				Name:         "build-step-ends-with-invalid",
 				Image:        "image",
 				Env:          implicitEnvVars,
 				VolumeMounts: implicitVolumeMounts,