Separator is no longer prepended when prefix is empty on podman generate systemd

When podman generate systemd is invoked, it previously did not check if
container-prefix or pod-prefix are empty. When these are empty, the file name
starts with the separator, which is hyphen by default. This results in files
like '-containername.service'.

The code now checks if these prefixes are empty. If they are, the filename no
longer adds a separator. Instead, it uses name or ID of the container or pod.

Closes #13272

Signed-off-by: Nirmal Patel <npate012@gmail.com>

7 files changed, 180 insertions, 13 deletions

diff --git a/pkg/api/handlers/libpod/generate.go b/pkg/api/handlers/libpod/generate.go
index 7e08dd4a8..28785b00d 100644
--- a/pkg/api/handlers/libpod/generate.go
+++ b/pkg/api/handlers/libpod/generate.go
@@ -25,18 +25,15 @@ func GenerateSystemd(w http.ResponseWriter, r *http.Request) {
 		RestartSec       uint     `schema:"restartSec"`
 		StopTimeout      uint     `schema:"stopTimeout"`
 		StartTimeout     uint     `schema:"startTimeout"`
-		ContainerPrefix  string   `schema:"containerPrefix"`
-		PodPrefix        string   `schema:"podPrefix"`
-		Separator        string   `schema:"separator"`
+		ContainerPrefix  *string  `schema:"containerPrefix"`
+		PodPrefix        *string  `schema:"podPrefix"`
+		Separator        *string  `schema:"separator"`
 		Wants            []string `schema:"wants"`
 		After            []string `schema:"after"`
 		Requires         []string `schema:"requires"`
 	}{
-		StartTimeout:    0,
-		StopTimeout:     util.DefaultContainerConfig().Engine.StopTimeout,
-		ContainerPrefix: "container",
-		PodPrefix:       "pod",
-		Separator:       "-",
+		StartTimeout: 0,
+		StopTimeout:  util.DefaultContainerConfig().Engine.StopTimeout,
 	}
 
 	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
@@ -44,6 +41,21 @@ func GenerateSystemd(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	var ContainerPrefix = "container"
+	if query.ContainerPrefix != nil {
+		ContainerPrefix = *query.ContainerPrefix
+	}
+
+	var PodPrefix = "pod"
+	if query.PodPrefix != nil {
+		PodPrefix = *query.PodPrefix
+	}
+
+	var Separator = "-"
+	if query.Separator != nil {
+		Separator = *query.Separator
+	}
+
 	containerEngine := abi.ContainerEngine{Libpod: runtime}
 	options := entities.GenerateSystemdOptions{
 		Name:             query.Name,
@@ -53,9 +65,9 @@ func GenerateSystemd(w http.ResponseWriter, r *http.Request) {
 		RestartPolicy:    query.RestartPolicy,
 		StartTimeout:     &query.StartTimeout,
 		StopTimeout:      &query.StopTimeout,
-		ContainerPrefix:  query.ContainerPrefix,
-		PodPrefix:        query.PodPrefix,
-		Separator:        query.Separator,
+		ContainerPrefix:  ContainerPrefix,
+		PodPrefix:        PodPrefix,
+		Separator:        Separator,
 		RestartSec:       &query.RestartSec,
 		Wants:            query.Wants,
 		After:            query.After,
diff --git a/pkg/systemd/generate/common.go b/pkg/systemd/generate/common.go
index a6f8f7cd4..e53d37897 100644
--- a/pkg/systemd/generate/common.go
+++ b/pkg/systemd/generate/common.go
@@ -137,3 +137,17 @@ func removeArg(arg string, args []string) []string {
 	}
 	return newArgs
 }
+
+// This function is used to get name of systemd service from prefix, separator, and
+// container/pod name. If prefix is empty, the service name does not include the
+// separator. This is to avoid a situation where service name starts with the separator
+// which is usually hyphen.
+func getServiceName(prefix string, separator string, name string) string {
+	serviceName := name
+
+	if len(prefix) > 0 {
+		serviceName = prefix + separator + name
+	}
+
+	return serviceName
+}
diff --git a/pkg/systemd/generate/containers.go b/pkg/systemd/generate/containers.go
index ea829c810..c01bb1baf 100644
--- a/pkg/systemd/generate/containers.go
+++ b/pkg/systemd/generate/containers.go
@@ -236,7 +236,9 @@ func containerServiceName(ctr *libpod.Container, options entities.GenerateSystem
 	if options.Name {
 		nameOrID = ctr.Name()
 	}
-	serviceName := fmt.Sprintf("%s%s%s", options.ContainerPrefix, options.Separator, nameOrID)
+
+	serviceName := getServiceName(options.ContainerPrefix, options.Separator, nameOrID)
+
 	return nameOrID, serviceName
 }
 
diff --git a/pkg/systemd/generate/containers_test.go b/pkg/systemd/generate/containers_test.go
index 2f653a4b9..b9bf7c317 100644
--- a/pkg/systemd/generate/containers_test.go
+++ b/pkg/systemd/generate/containers_test.go
@@ -91,6 +91,30 @@ Type=forking
 WantedBy=default.target
 `
 
+	goodNameEmptyContainerPrefix := `# foobar.service
+# autogenerated by Podman CI
+
+[Unit]
+Description=Podman foobar.service
+Documentation=man:podman-generate-systemd(1)
+Wants=network-online.target
+After=network-online.target
+RequiresMountsFor=/var/run/containers/storage
+
+[Service]
+Environment=PODMAN_SYSTEMD_UNIT=%n
+Restart=on-failure
+TimeoutStopSec=70
+ExecStart=/usr/bin/podman start foobar
+ExecStop=/usr/bin/podman stop -t 10 foobar
+ExecStopPost=/usr/bin/podman stop -t 10 foobar
+PIDFile=/run/containers/storage/overlay-containers/639c53578af4d84b8800b4635fa4e680ee80fd67e0e6a2d4eea48d1e3230f401/userdata/conmon.pid
+Type=forking
+
+[Install]
+WantedBy=default.target
+`
+
 	goodNameCustomWants := `# container-foobar.service
 # autogenerated by Podman CI
 
@@ -1206,6 +1230,24 @@ WantedBy=default.target
 			false,
 			true,
 		},
+		{"good with name and empty container-prefix",
+			containerInfo{
+				Executable:        "/usr/bin/podman",
+				ServiceName:       "foobar",
+				ContainerNameOrID: "foobar",
+				PIDFile:           "/run/containers/storage/overlay-containers/639c53578af4d84b8800b4635fa4e680ee80fd67e0e6a2d4eea48d1e3230f401/userdata/conmon.pid",
+				StopTimeout:       10,
+				PodmanVersion:     "CI",
+				EnvVariable:       define.EnvVariable,
+				GraphRoot:         "/var/lib/containers/storage",
+				RunRoot:           "/var/run/containers/storage",
+			},
+			goodNameEmptyContainerPrefix,
+			false,
+			false,
+			false,
+			false,
+		},
 	}
 	for _, tt := range tests {
 		test := tt
diff --git a/pkg/systemd/generate/pods.go b/pkg/systemd/generate/pods.go
index 003c23e77..78ae6391b 100644
--- a/pkg/systemd/generate/pods.go
+++ b/pkg/systemd/generate/pods.go
@@ -242,7 +242,8 @@ func generatePodInfo(pod *libpod.Pod, options entities.GenerateSystemdOptions) (
 		nameOrID = pod.Name()
 		ctrNameOrID = infraCtr.Name()
 	}
-	serviceName := fmt.Sprintf("%s%s%s", options.PodPrefix, options.Separator, nameOrID)
+
+	serviceName := getServiceName(options.PodPrefix, options.Separator, nameOrID)
 
 	info := podInfo{
 		ServiceName:       serviceName,
diff --git a/pkg/systemd/generate/pods_test.go b/pkg/systemd/generate/pods_test.go
index b37e0825b..dcb18780c 100644
--- a/pkg/systemd/generate/pods_test.go
+++ b/pkg/systemd/generate/pods_test.go
@@ -67,6 +67,32 @@ WantedBy=default.target
 	podGood := serviceInfo + headerInfo + podContent
 	podGoodNoHeaderInfo := serviceInfo + podContent
 
+	podGoodWithEmptyPrefix := `# 123abc.service
+# autogenerated by Podman CI
+
+[Unit]
+Description=Podman 123abc.service
+Documentation=man:podman-generate-systemd(1)
+Wants=network-online.target
+After=network-online.target
+RequiresMountsFor=/var/run/containers/storage
+Requires=container-1.service container-2.service
+Before=container-1.service container-2.service
+
+[Service]
+Environment=PODMAN_SYSTEMD_UNIT=%n
+Restart=on-failure
+TimeoutStopSec=102
+ExecStart=/usr/bin/podman start jadda-jadda-infra
+ExecStop=/usr/bin/podman stop -t 42 jadda-jadda-infra
+ExecStopPost=/usr/bin/podman stop -t 42 jadda-jadda-infra
+PIDFile=/run/containers/storage/overlay-containers/639c53578af4d84b8800b4635fa4e680ee80fd67e0e6a2d4eea48d1e3230f401/userdata/conmon.pid
+Type=forking
+
+[Install]
+WantedBy=default.target
+`
+
 	podGoodCustomWants := `# pod-123abc.service
 # autogenerated by Podman CI
 
@@ -580,6 +606,24 @@ WantedBy=default.target
 			false,
 			false,
 		},
+		{"pod with empty pod-prefix",
+			podInfo{
+				Executable:       "/usr/bin/podman",
+				ServiceName:      "123abc",
+				InfraNameOrID:    "jadda-jadda-infra",
+				PIDFile:          "/run/containers/storage/overlay-containers/639c53578af4d84b8800b4635fa4e680ee80fd67e0e6a2d4eea48d1e3230f401/userdata/conmon.pid",
+				StopTimeout:      42,
+				PodmanVersion:    "CI",
+				GraphRoot:        "/var/lib/containers/storage",
+				RunRoot:          "/var/run/containers/storage",
+				RequiredServices: []string{"container-1", "container-2"},
+				CreateCommand:    []string{"podman", "pod", "create", "--name", "foo", "bar=arg with space"},
+			},
+			podGoodWithEmptyPrefix,
+			false,
+			false,
+			false,
+		},
 	}
 
 	for _, tt := range tests {
diff --git a/test/e2e/generate_systemd_test.go b/test/e2e/generate_systemd_test.go
index 55b9a8037..e4b854332 100644
--- a/test/e2e/generate_systemd_test.go
+++ b/test/e2e/generate_systemd_test.go
@@ -423,6 +423,20 @@ var _ = Describe("Podman generate systemd", func() {
 
 	})
 
+	It("podman generate systemd --container-prefix ''", func() {
+		n := podmanTest.Podman([]string{"create", "--name", "foo", "alpine", "top"})
+		n.WaitWithDefaultTimeout()
+		Expect(n).Should(Exit(0))
+
+		session := podmanTest.Podman([]string{"generate", "systemd", "--name", "--container-prefix", "", "foo"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		// Grepping the output (in addition to unit tests)
+		Expect(session.OutputToString()).To(ContainSubstring("# foo.service"))
+
+	})
+
 	It("podman generate systemd --separator _", func() {
 		n := podmanTest.Podman([]string{"create", "--name", "foo", "alpine", "top"})
 		n.WaitWithDefaultTimeout()
@@ -485,6 +499,44 @@ var _ = Describe("Podman generate systemd", func() {
 		Expect(session.OutputToString()).To(ContainSubstring("BindsTo=p_foo.service"))
 	})
 
+	It("podman generate systemd pod --pod-prefix '' --container-prefix '' --separator _ change all prefixes/separator", func() {
+		n := podmanTest.Podman([]string{"pod", "create", "--name", "foo"})
+		n.WaitWithDefaultTimeout()
+		Expect(n).Should(Exit(0))
+
+		n = podmanTest.Podman([]string{"create", "--pod", "foo", "--name", "foo-1", "alpine", "top"})
+		n.WaitWithDefaultTimeout()
+		Expect(n).Should(Exit(0))
+
+		n = podmanTest.Podman([]string{"create", "--pod", "foo", "--name", "foo-2", "alpine", "top"})
+		n.WaitWithDefaultTimeout()
+		Expect(n).Should(Exit(0))
+
+		// test systemd generate with empty pod prefix
+		session1 := podmanTest.Podman([]string{"generate", "systemd", "--pod-prefix", "", "--name", "foo"})
+		session1.WaitWithDefaultTimeout()
+		Expect(session1).Should(Exit(0))
+
+		// Grepping the output (in addition to unit tests)
+		Expect(session1.OutputToString()).To(ContainSubstring("# foo.service"))
+		Expect(session1.OutputToString()).To(ContainSubstring("Requires=container-foo-1.service container-foo-2.service"))
+		Expect(session1.OutputToString()).To(ContainSubstring("# container-foo-1.service"))
+		Expect(session1.OutputToString()).To(ContainSubstring("BindsTo=foo.service"))
+
+		// test systemd generate with empty container and pod prefix
+		session2 := podmanTest.Podman([]string{"generate", "systemd", "--container-prefix", "", "--pod-prefix", "", "--separator", "_", "--name", "foo"})
+		session2.WaitWithDefaultTimeout()
+		Expect(session2).Should(Exit(0))
+
+		// Grepping the output (in addition to unit tests)
+		Expect(session2.OutputToString()).To(ContainSubstring("# foo.service"))
+		Expect(session2.OutputToString()).To(ContainSubstring("Requires=foo-1.service foo-2.service"))
+		Expect(session2.OutputToString()).To(ContainSubstring("# foo-1.service"))
+		Expect(session2.OutputToString()).To(ContainSubstring("# foo-2.service"))
+		Expect(session2.OutputToString()).To(ContainSubstring("BindsTo=foo.service"))
+
+	})
+
 	It("podman generate systemd pod with containers --new", func() {
 		tmpDir, err := ioutil.TempDir("", "")
 		Expect(err).To(BeNil())