From ae2c0898434dad663ad0f60545d7f56144d4c0a8 Mon Sep 17 00:00:00 2001
From: Bohan Chen <bochen@pivotal.io>
Date: Wed, 28 Apr 2021 16:52:07 -0400
Subject: [PATCH] Remove k8s-topgun DNS proxy tests

Added one smoke test to verify that concourse containers can resolve
cluster addresses.

Signed-off-by: Bohan Chen <bochen@pivotal.io>
Co-authored-by: Taylor Silva <tsilva@pivotal.io>
---
 topgun/k8s/dns_proxy_test.go | 119 +++++------------------------------
 1 file changed, 14 insertions(+), 105 deletions(-)

diff --git a/topgun/k8s/dns_proxy_test.go b/topgun/k8s/dns_proxy_test.go
index dc21f2643..89af2af9b 100644
--- a/topgun/k8s/dns_proxy_test.go
+++ b/topgun/k8s/dns_proxy_test.go
@@ -1,10 +1,7 @@
 package k8s_test
 
 import (
-	"log"
-
 	. "github.com/onsi/ginkgo"
-	. "github.com/onsi/ginkgo/extensions/table"
 	. "github.com/onsi/gomega"
 )
 
@@ -13,7 +10,7 @@ var _ = Describe("DNS Resolution", func() {
 	var atc Endpoint
 
 	BeforeEach(func() {
-		setReleaseNameAndNamespace("dp")
+		setReleaseNameAndNamespace("dns")
 	})
 
 	AfterEach(func() {
@@ -25,118 +22,30 @@ var _ = Describe("DNS Resolution", func() {
 		return releaseName + "-web." + namespace + ".svc.cluster.local:8080/api/v1/info"
 	}
 
-	var shortAddress = func() string {
-		return releaseName + "-web:8080/api/v1/info"
-	}
-
-	type Case struct {
-		// args
-		enableDnsProxy  string
-		dnsServer       string
-		addressFunction func() string
-
-		// expectations
-		shouldWork bool
-	}
-
 	const containerdRuntime = "containerd"
 	const guardianRuntime = "guardian"
 
-	var setupDeployment = func(runtime string, dnsProxyEnable, dnsServer string) {
-		args := []string{
-			`--set=worker.replicas=1`,
-			`--set-string=concourse.worker.runtime=` + runtime,
-		}
-		switch {
-		case runtime == containerdRuntime:
-			args = append(args, `--set-string=concourse.worker.containerd.dnsProxyEnable=`+dnsProxyEnable)
-			if dnsServer != "" {
-				args = append(args,
-					`--set=concourse.worker.containerd.dnsServers=['`+dnsServer+`']`,
-				)
+	DNSShouldWork := func(runtime string) {
+		It("can reach local k8s services", func() {
+			args := []string{
+				`--set=worker.replicas=1`,
+				`--set-string=concourse.worker.runtime=` + runtime,
 			}
-		case runtime == guardianRuntime:
-			args = append(args, `--set-string=concourse.worker.garden.dnsProxyEnable=`+dnsProxyEnable)
-			if dnsServer != "" {
-				// garden flags aren't explicityly defined in the chart, so add them as env vars directly
-				args = append(args,
-					`--set=worker.env[0].name=CONCOURSE_GARDEN_DNS_SERVER`,
-					`--set=worker.env[0].value=`+dnsServer)
-			}
-		default:
-			log.Fatalf("Invalid runtime type %s. Test aborted.", runtime)
-			return
-		}
+			deployConcourseChart(releaseName, args...)
+			atc = waitAndLogin(namespace, releaseName+"-web")
 
-		deployConcourseChart(releaseName, args...)
-		atc = waitAndLogin(namespace, releaseName+"-web")
-	}
+			sess := fly.Start("execute", "-c", "tasks/dns-proxy-task.yml", "-v", "url="+fullAddress())
+			<-sess.Exited
 
-	expectedDnsProxyBehaviour := func(runtime string) {
-		DescribeTable("different proxy settings",
-			func(c Case) {
-				setupDeployment(runtime, c.enableDnsProxy, c.dnsServer)
-
-				sess := fly.Start("execute", "-c", "tasks/dns-proxy-task.yml", "-v", "url="+c.addressFunction())
-				<-sess.Exited
-
-				if !c.shouldWork {
-					Expect(sess.ExitCode()).ToNot(BeZero())
-					return
-				}
-
-				Expect(sess.ExitCode()).To(BeZero())
-			},
-			// local proxy will pass through requests to the k8s native dns
-			Entry("Proxy Enabled, with full service name", Case{
-				enableDnsProxy:  "true",
-				addressFunction: fullAddress,
-				shouldWork:      true,
-			}),
-			// the short address is expanded into the full addresses with the help of
-			// the `search` configuration in the resolv.conf. But our implementation
-			// of the proxy server kinda just ignores this configuration. So short
-			// addresses won't ever work
-			Entry("Proxy Enabled, with short service name", Case{
-				enableDnsProxy:  "true",
-				addressFunction: shortAddress,
-				shouldWork:      false,
-			}),
-			// no dns proxy = the super powerful k8s native dns
-			Entry("Proxy Disabled, with full service name", Case{
-				enableDnsProxy:  "false",
-				addressFunction: fullAddress,
-				shouldWork:      true,
-			}),
-			// no dns proxy = the super powerful k8s native dns
-			Entry("Proxy Disabled, with short service name", Case{
-				enableDnsProxy:  "false",
-				addressFunction: shortAddress,
-				shouldWork:      true,
-			}),
-			// the public 8.8.8.8 server won't be able to resolve k8s addresses
-			Entry("Adding extra dns server, with Proxy Disabled and full address", Case{
-				enableDnsProxy:  "false",
-				dnsServer:       "8.8.8.8",
-				addressFunction: fullAddress,
-				shouldWork:      false,
-			}),
-			// dns requests hits the 8.8.8.8 server first, as long as it doesn't time
-			// out, it should fail to resolve and end the search chain, skipping the proxy
-			Entry("Adding extra dns server, with Proxy Enabled and full address", Case{
-				enableDnsProxy:  "true",
-				dnsServer:       "8.8.8.8",
-				addressFunction: fullAddress,
-				shouldWork:      false,
-			}),
-		)
+			Expect(sess.ExitCode()).To(BeZero())
+		})
 	}
 
 	Context("with gdn backend", func() {
-		expectedDnsProxyBehaviour(guardianRuntime)
+		DNSShouldWork(guardianRuntime)
 	})
 
 	Context("with containerd backend", func() {
-		expectedDnsProxyBehaviour(containerdRuntime)
+		DNSShouldWork(containerdRuntime)
 	})
 })