Add generate systemd -e/--env option

-e/--env option sets environment variables to the systemd unit files.

Fixes: #15523

Signed-off-by: Toshiki Sonoda <sonoda.toshiki@fujitsu.com>

11 files changed, 263 insertions, 150 deletions

diff --git a/cmd/podman/generate/systemd.go b/cmd/podman/generate/systemd.go
index e40416534..a7cdd9bfe 100644
--- a/cmd/podman/generate/systemd.go
+++ b/cmd/podman/generate/systemd.go
@@ -13,6 +13,7 @@ import (
 	"github.com/containers/podman/v4/cmd/podman/registry"
 	"github.com/containers/podman/v4/cmd/podman/utils"
 	"github.com/containers/podman/v4/pkg/domain/entities"
+	envLib "github.com/containers/podman/v4/pkg/env"
 	systemDefine "github.com/containers/podman/v4/pkg/systemd/define"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
@@ -28,9 +29,11 @@ const (
 	wantsFlagName             = "wants"
 	afterFlagName             = "after"
 	requiresFlagName          = "requires"
+	envFlagName               = "env"
 )
 
 var (
+	envInput           []string
 	files              bool
 	format             string
 	systemdRestart     string
@@ -109,6 +112,9 @@ func init() {
 	flags.StringArrayVar(&systemdOptions.Requires, requiresFlagName, nil, "Similar to wants, but declares stronger requirement dependencies")
 	_ = systemdCmd.RegisterFlagCompletionFunc(requiresFlagName, completion.AutocompleteNone)
 
+	flags.StringArrayVarP(&envInput, envFlagName, "e", nil, "Set environment variables to the systemd unit files")
+	_ = systemdCmd.RegisterFlagCompletionFunc(envFlagName, completion.AutocompleteNone)
+
 	flags.SetNormalizeFunc(utils.TimeoutAliasFlags)
 }
 
@@ -141,6 +147,13 @@ func systemd(cmd *cobra.Command, args []string) error {
 	if cmd.Flags().Changed(stopTimeoutCompatFlagName) {
 		setStopTimeout++
 	}
+	if cmd.Flags().Changed(envFlagName) {
+		cliEnv, err := envLib.ParseSlice(envInput)
+		if err != nil {
+			return fmt.Errorf("error parsing environment variables: %w", err)
+		}
+		systemdOptions.AdditionalEnvVariables = envLib.Slice(cliEnv)
+	}
 	switch setStopTimeout {
 	case 1:
 		systemdOptions.StopTimeout = &stopTimeout
diff --git a/docs/source/markdown/podman-generate-systemd.1.md b/docs/source/markdown/podman-generate-systemd.1.md
index 88dff2a45..1ada6bd3f 100644
--- a/docs/source/markdown/podman-generate-systemd.1.md
+++ b/docs/source/markdown/podman-generate-systemd.1.md
@@ -44,6 +44,12 @@ User-defined dependencies will be appended to the generated unit file, but any e
 
 Set the systemd unit name prefix for containers. The default is *container*.
 
+#### **--env**, **-e**=*env*
+
+Set environment variables to the systemd unit files.
+
+If an environment variable is specified without a value, Podman will check the host environment for a value and set the variable only if it is set on the host. As a special case, if an environment variable ending in __*__ is specified without a value, Podman will search the host environment for variables starting with the prefix and will add those variables to the systemd unit files.
+
 #### **--files**, **-f**
 
 Generate files instead of printing to stdout.  The generated files are named {container,pod}-{ID,name}.service and will be placed in the current working directory.
diff --git a/pkg/api/handlers/libpod/generate.go b/pkg/api/handlers/libpod/generate.go
index 48c4c59e1..431927ac5 100644
--- a/pkg/api/handlers/libpod/generate.go
+++ b/pkg/api/handlers/libpod/generate.go
@@ -17,20 +17,21 @@ func GenerateSystemd(w http.ResponseWriter, r *http.Request) {
 	runtime := r.Context().Value(api.RuntimeKey).(*libpod.Runtime)
 	decoder := r.Context().Value(api.DecoderKey).(*schema.Decoder)
 	query := struct {
-		Name             bool     `schema:"useName"`
-		New              bool     `schema:"new"`
-		NoHeader         bool     `schema:"noHeader"`
-		TemplateUnitFile bool     `schema:"templateUnitFile"`
-		RestartPolicy    *string  `schema:"restartPolicy"`
-		RestartSec       uint     `schema:"restartSec"`
-		StopTimeout      uint     `schema:"stopTimeout"`
-		StartTimeout     uint     `schema:"startTimeout"`
-		ContainerPrefix  *string  `schema:"containerPrefix"`
-		PodPrefix        *string  `schema:"podPrefix"`
-		Separator        *string  `schema:"separator"`
-		Wants            []string `schema:"wants"`
-		After            []string `schema:"after"`
-		Requires         []string `schema:"requires"`
+		Name                   bool     `schema:"useName"`
+		New                    bool     `schema:"new"`
+		NoHeader               bool     `schema:"noHeader"`
+		TemplateUnitFile       bool     `schema:"templateUnitFile"`
+		RestartPolicy          *string  `schema:"restartPolicy"`
+		RestartSec             uint     `schema:"restartSec"`
+		StopTimeout            uint     `schema:"stopTimeout"`
+		StartTimeout           uint     `schema:"startTimeout"`
+		ContainerPrefix        *string  `schema:"containerPrefix"`
+		PodPrefix              *string  `schema:"podPrefix"`
+		Separator              *string  `schema:"separator"`
+		Wants                  []string `schema:"wants"`
+		After                  []string `schema:"after"`
+		Requires               []string `schema:"requires"`
+		AdditionalEnvVariables []string `schema:"additionalEnvVariables"`
 	}{
 		StartTimeout: 0,
 		StopTimeout:  util.DefaultContainerConfig().Engine.StopTimeout,
@@ -58,20 +59,21 @@ func GenerateSystemd(w http.ResponseWriter, r *http.Request) {
 
 	containerEngine := abi.ContainerEngine{Libpod: runtime}
 	options := entities.GenerateSystemdOptions{
-		Name:             query.Name,
-		New:              query.New,
-		NoHeader:         query.NoHeader,
-		TemplateUnitFile: query.TemplateUnitFile,
-		RestartPolicy:    query.RestartPolicy,
-		StartTimeout:     &query.StartTimeout,
-		StopTimeout:      &query.StopTimeout,
-		ContainerPrefix:  ContainerPrefix,
-		PodPrefix:        PodPrefix,
-		Separator:        Separator,
-		RestartSec:       &query.RestartSec,
-		Wants:            query.Wants,
-		After:            query.After,
-		Requires:         query.Requires,
+		Name:                   query.Name,
+		New:                    query.New,
+		NoHeader:               query.NoHeader,
+		TemplateUnitFile:       query.TemplateUnitFile,
+		RestartPolicy:          query.RestartPolicy,
+		StartTimeout:           &query.StartTimeout,
+		StopTimeout:            &query.StopTimeout,
+		ContainerPrefix:        ContainerPrefix,
+		PodPrefix:              PodPrefix,
+		Separator:              Separator,
+		RestartSec:             &query.RestartSec,
+		Wants:                  query.Wants,
+		After:                  query.After,
+		Requires:               query.Requires,
+		AdditionalEnvVariables: query.AdditionalEnvVariables,
 	}
 
 	report, err := containerEngine.GenerateSystemd(r.Context(), utils.GetName(r), options)
diff --git a/pkg/api/server/register_generate.go b/pkg/api/server/register_generate.go
index 82fbe3d09..ac2818db0 100644
--- a/pkg/api/server/register_generate.go
+++ b/pkg/api/server/register_generate.go
@@ -93,6 +93,13 @@ func (s *APIServer) registerGenerateHandlers(r *mux.Router) error {
 	//        type: string
 	//    default: []
 	//    description: Systemd Requires list for the container or pods.
+	//  - in: query
+	//    name: additionalEnvVariables
+	//    type: array
+	//    items:
+	//        type: string
+	//    default: []
+	//    description: Set environment variables to the systemd unit files.
 	// produces:
 	// - application/json
 	// responses:
diff --git a/pkg/bindings/generate/types.go b/pkg/bindings/generate/types.go
index 25c398c8b..31b43897c 100644
--- a/pkg/bindings/generate/types.go
+++ b/pkg/bindings/generate/types.go
@@ -38,4 +38,6 @@ type SystemdOptions struct {
 	After *[]string
 	// Requires - systemd requires list for the container or pods
 	Requires *[]string
+	// AdditionalEnvVariables - Sets environment variables to a systemd unit file
+	AdditionalEnvVariables *[]string
 }
diff --git a/pkg/bindings/generate/types_systemd_options.go b/pkg/bindings/generate/types_systemd_options.go
index 4d436945b..3aec33a54 100644
--- a/pkg/bindings/generate/types_systemd_options.go
+++ b/pkg/bindings/generate/types_systemd_options.go
@@ -226,3 +226,18 @@ func (o *SystemdOptions) GetRequires() []string {
 	}
 	return *o.Requires
 }
+
+// WithAdditionalEnvVariables set field AdditionalEnvVariables to given value
+func (o *SystemdOptions) WithAdditionalEnvVariables(value []string) *SystemdOptions {
+	o.AdditionalEnvVariables = &value
+	return o
+}
+
+// GetAdditionalEnvVariables returns value of field AdditionalEnvVariables
+func (o *SystemdOptions) GetAdditionalEnvVariables() []string {
+	if o.AdditionalEnvVariables == nil {
+		var z []string
+		return z
+	}
+	return *o.AdditionalEnvVariables
+}
diff --git a/pkg/domain/entities/generate.go b/pkg/domain/entities/generate.go
index f18e79b47..314996497 100644
--- a/pkg/domain/entities/generate.go
+++ b/pkg/domain/entities/generate.go
@@ -4,34 +4,21 @@ import "io"
 
 // GenerateSystemdOptions control the generation of systemd unit files.
 type GenerateSystemdOptions struct {
-	// Name - use container/pod name instead of its ID.
-	Name bool
-	// New - create a new container instead of starting a new one.
-	New bool
-	// RestartPolicy - systemd restart policy.
-	RestartPolicy *string
-	// RestartSec - systemd service restartsec. Configures the time to sleep before restarting a service.
-	RestartSec *uint
-	// StartTimeout - time when starting the container.
-	StartTimeout *uint
-	// StopTimeout - time when stopping the container.
-	StopTimeout *uint
-	// ContainerPrefix - systemd unit name prefix for containers
-	ContainerPrefix string
-	// PodPrefix - systemd unit name prefix for pods
-	PodPrefix string
-	// Separator - systemd unit name separator between name/id and prefix
-	Separator string
-	// NoHeader - skip header generation
-	NoHeader bool
-	// TemplateUnitFile - make use of %i and %I to differentiate between the different instances of the unit
-	TemplateUnitFile bool
-	// Wants - systemd wants list for the container or pods
-	Wants []string
-	// After - systemd after list for the container or pods
-	After []string
-	// Requires - systemd requires list for the container or pods
-	Requires []string
+	Name                   bool
+	New                    bool
+	RestartPolicy          *string
+	RestartSec             *uint
+	StartTimeout           *uint
+	StopTimeout            *uint
+	ContainerPrefix        string
+	PodPrefix              string
+	Separator              string
+	NoHeader               bool
+	TemplateUnitFile       bool
+	Wants                  []string
+	After                  []string
+	Requires               []string
+	AdditionalEnvVariables []string
 }
 
 // GenerateSystemdReport
diff --git a/pkg/domain/infra/tunnel/generate.go b/pkg/domain/infra/tunnel/generate.go
index ed63d363a..d3c3638cb 100644
--- a/pkg/domain/infra/tunnel/generate.go
+++ b/pkg/domain/infra/tunnel/generate.go
@@ -19,7 +19,8 @@ func (ic *ContainerEngine) GenerateSystemd(ctx context.Context, nameOrID string,
 		WithSeparator(opts.Separator).
 		WithWants(opts.Wants).
 		WithAfter(opts.After).
-		WithRequires(opts.Requires)
+		WithRequires(opts.Requires).
+		WithAdditionalEnvVariables(opts.AdditionalEnvVariables)
 
 	if opts.StartTimeout != nil {
 		options.WithStartTimeout(*opts.StartTimeout)
diff --git a/pkg/systemd/generate/containers.go b/pkg/systemd/generate/containers.go
index 1f8c519b7..6f546b0ab 100644
--- a/pkg/systemd/generate/containers.go
+++ b/pkg/systemd/generate/containers.go
@@ -22,85 +22,40 @@ import (
 // containerInfo contains data required for generating a container's systemd
 // unit file.
 type containerInfo struct {
-	// ServiceName of the systemd service.
-	ServiceName string
-	// Name or ID of the container.
-	ContainerNameOrID string
-	// Type of the unit.
-	Type string
-	// NotifyAccess of the unit.
-	NotifyAccess string
-	// StopTimeout sets the timeout Podman waits before killing the container
-	// during service stop.
-	StopTimeout uint
-	// RestartPolicy of the systemd unit (e.g., no, on-failure, always).
-	RestartPolicy string
-	// Custom number of restart attempts.
-	StartLimitBurst string
-	// PIDFile of the service. Required for forking services. Must point to the
-	// PID of the associated conmon process.
-	PIDFile string
-	// ContainerIDFile to be used in the unit.
-	ContainerIDFile string
-	// GenerateTimestamp, if set the generated unit file has a time stamp.
-	GenerateTimestamp bool
-	// BoundToServices are the services this service binds to.  Note that this
-	// service runs after them.
-	BoundToServices []string
-	// PodmanVersion for the header. Will be set internally. Will be auto-filled
-	// if left empty.
-	PodmanVersion string
-	// Executable is the path to the podman executable. Will be auto-filled if
-	// left empty.
-	Executable string
-	// RootFlags contains the root flags which were used to create the container
-	// Only used with --new
-	RootFlags string
-	// TimeStamp at the time of creating the unit file. Will be set internally.
-	TimeStamp string
-	// CreateCommand is the full command plus arguments of the process the
-	// container has been created with.
-	CreateCommand []string
-	// containerEnv stores the container environment variables
-	containerEnv []string
-	// ExtraEnvs contains the container environment variables referenced
-	// by only the key in the container create command, e.g. --env FOO.
-	// This is only used with --new
-	ExtraEnvs []string
-	// EnvVariable is generate.EnvVariable and must not be set.
-	EnvVariable string
-	// ExecStartPre of the unit.
-	ExecStartPre string
-	// ExecStart of the unit.
-	ExecStart string
-	// TimeoutStartSec of the unit.
-	TimeoutStartSec uint
-	// TimeoutStopSec of the unit.
-	TimeoutStopSec uint
-	// ExecStop of the unit.
-	ExecStop string
-	// ExecStopPost of the unit.
-	ExecStopPost string
-	// Removes autogenerated by Podman and timestamp if set to true
-	GenerateNoHeader bool
-	// If not nil, the container is part of the pod.  We can use the
-	// podInfo to extract the relevant data.
-	Pod *podInfo
-	// Location of the GraphRoot for the container.  Required for ensuring the
-	// volume has finished mounting when coming online at boot.
-	GraphRoot string
-	// Location of the RunRoot for the container.  Required for ensuring the tmpfs
-	// or volume exists and is mounted when coming online at boot.
-	RunRoot string
-	// Add %i and %I to description and execute parts
-	IdentifySpecifier bool
-	// Wants are the list of services that this service is (weak) dependent on. This
-	// option does not influence the order in which services are started or stopped.
-	Wants []string
-	// After ordering dependencies between the list of services and this service.
-	After []string
-	// Similar to Wants, but declares a stronger requirement dependency.
-	Requires []string
+	ServiceName            string
+	ContainerNameOrID      string
+	Type                   string
+	NotifyAccess           string
+	StopTimeout            uint
+	RestartPolicy          string
+	StartLimitBurst        string
+	PIDFile                string
+	ContainerIDFile        string
+	GenerateTimestamp      bool
+	BoundToServices        []string
+	PodmanVersion          string
+	Executable             string
+	RootFlags              string
+	TimeStamp              string
+	CreateCommand          []string
+	containerEnv           []string
+	ExtraEnvs              []string
+	EnvVariable            string
+	AdditionalEnvVariables []string
+	ExecStartPre           string
+	ExecStart              string
+	TimeoutStartSec        uint
+	TimeoutStopSec         uint
+	ExecStop               string
+	ExecStopPost           string
+	GenerateNoHeader       bool
+	Pod                    *podInfo
+	GraphRoot              string
+	RunRoot                string
+	IdentifySpecifier      bool
+	Wants                  []string
+	After                  []string
+	Requires               []string
 }
 
 const containerTemplate = headerTemplate + `
@@ -127,6 +82,10 @@ Environment={{{{.EnvVariable}}}}=%n{{{{- if (eq .IdentifySpecifier true) }}}}-%i
 {{{{- if .ExtraEnvs}}}}
 Environment={{{{- range $index, $value := .ExtraEnvs -}}}}{{{{if $index}}}} {{{{end}}}}{{{{ $value }}}}{{{{end}}}}
 {{{{- end}}}}
+{{{{- if .AdditionalEnvVariables}}}}
+{{{{- range $index, $value := .AdditionalEnvVariables -}}}}{{{{if $index}}}}{{{{end}}}}
+Environment={{{{ $value }}}}{{{{end}}}}
+{{{{- end}}}}
 Restart={{{{.RestartPolicy}}}}
 {{{{- if .StartLimitBurst}}}}
 StartLimitBurst={{{{.StartLimitBurst}}}}
@@ -211,19 +170,20 @@ func generateContainerInfo(ctr *libpod.Container, options entities.GenerateSyste
 	envs := config.Spec.Process.Env
 
 	info := containerInfo{
-		ServiceName:       serviceName,
-		ContainerNameOrID: nameOrID,
-		RestartPolicy:     define.DefaultRestartPolicy,
-		PIDFile:           conmonPidFile,
-		TimeoutStartSec:   startTimeout,
-		StopTimeout:       stopTimeout,
-		GenerateTimestamp: true,
-		CreateCommand:     createCommand,
-		RunRoot:           runRoot,
-		containerEnv:      envs,
-		Wants:             options.Wants,
-		After:             options.After,
-		Requires:          options.Requires,
+		ServiceName:            serviceName,
+		ContainerNameOrID:      nameOrID,
+		RestartPolicy:          define.DefaultRestartPolicy,
+		PIDFile:                conmonPidFile,
+		TimeoutStartSec:        startTimeout,
+		StopTimeout:            stopTimeout,
+		GenerateTimestamp:      true,
+		CreateCommand:          createCommand,
+		RunRoot:                runRoot,
+		containerEnv:           envs,
+		Wants:                  options.Wants,
+		After:                  options.After,
+		Requires:               options.Requires,
+		AdditionalEnvVariables: options.AdditionalEnvVariables,
 	}
 
 	return &info, nil
@@ -324,6 +284,9 @@ func executeContainerTemplate(info *containerInfo, options entities.GenerateSyst
 	info.ExecStart = "{{{{.Executable}}}} start {{{{.ContainerNameOrID}}}}"
 	info.ExecStop = "{{{{.Executable}}}} stop {{{{if (ge .StopTimeout 0)}}}}-t {{{{.StopTimeout}}}}{{{{end}}}} {{{{.ContainerNameOrID}}}}"
 	info.ExecStopPost = "{{{{.Executable}}}} stop {{{{if (ge .StopTimeout 0)}}}}-t {{{{.StopTimeout}}}}{{{{end}}}} {{{{.ContainerNameOrID}}}}"
+	for i, env := range info.AdditionalEnvVariables {
+		info.AdditionalEnvVariables[i] = escapeSystemdArg(env)
+	}
 
 	// Assemble the ExecStart command when creating a new container.
 	//
diff --git a/pkg/systemd/generate/containers_test.go b/pkg/systemd/generate/containers_test.go
index 873cbfbb3..7f92e75b8 100644
--- a/pkg/systemd/generate/containers_test.go
+++ b/pkg/systemd/generate/containers_test.go
@@ -784,6 +784,33 @@ NotifyAccess=all
 WantedBy=default.target
 `
 
+	goodEnvironment := `# container-foobar.service
+# autogenerated by Podman CI
+
+[Unit]
+Description=Podman container-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
+Environment=FOO=abc
+Environment="BAR=my test"
+Environment=USER=%%a
+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
+`
+
 	goodNewWithRestartPolicy := `# jadda-jadda.service
 # autogenerated by Podman CI
 
@@ -1424,7 +1451,7 @@ WantedBy=default.target
 			false,
 			false,
 		},
-		{"good with environment variables",
+		{"good with container environment variables",
 			containerInfo{
 				Executable:        "/usr/bin/podman",
 				ServiceName:       "jadda-jadda",
@@ -1444,6 +1471,25 @@ WantedBy=default.target
 			false,
 			false,
 		},
+		{"good with systemd environment variables",
+			containerInfo{
+				Executable:             "/usr/bin/podman",
+				ServiceName:            "container-foobar",
+				ContainerNameOrID:      "foobar",
+				PIDFile:                "/run/containers/storage/overlay-containers/639c53578af4d84b8800b4635fa4e680ee80fd67e0e6a2d4eea48d1e3230f401/userdata/conmon.pid",
+				StopTimeout:            10,
+				PodmanVersion:          "CI",
+				GraphRoot:              "/var/lib/containers/storage",
+				RunRoot:                "/var/run/containers/storage",
+				EnvVariable:            define.EnvVariable,
+				AdditionalEnvVariables: []string{"FOO=abc", "BAR=my test", "USER=%a"},
+			},
+			goodEnvironment,
+			false,
+			false,
+			false,
+			false,
+		},
 		{"good with restart policy",
 			containerInfo{
 				Executable:        "/usr/bin/podman",
diff --git a/test/e2e/generate_systemd_test.go b/test/e2e/generate_systemd_test.go
index 45a2f1f86..f47abbc13 100644
--- a/test/e2e/generate_systemd_test.go
+++ b/test/e2e/generate_systemd_test.go
@@ -600,4 +600,75 @@ var _ = Describe("Podman generate systemd", func() {
 		Expect(session).Should(Exit(0))
 		Expect(session.OutputToString()).To(ContainSubstring(" --label key={{someval}}"))
 	})
+
+	It("podman generate systemd --env", func() {
+		session := podmanTest.RunTopContainer("test")
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "foo=bar", "-e", "hoge=fuga", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("Environment=foo=bar"))
+		Expect(session.OutputToString()).To(ContainSubstring("Environment=hoge=fuga"))
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "=bar", "-e", "hoge=fuga", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(125))
+		Expect(session.ErrorToString()).To(ContainSubstring("invalid environment variable"))
+
+		// Use -e/--env option with --new option
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "foo=bar", "-e", "hoge=fuga", "--new", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("Environment=foo=bar"))
+		Expect(session.OutputToString()).To(ContainSubstring("Environment=hoge=fuga"))
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "foo=bar", "-e", "=fuga", "--new", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(125))
+		Expect(session.ErrorToString()).To(ContainSubstring("invalid environment variable"))
+
+		// Escape systemd arguments
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "BAR=my test", "-e", "USER=%a", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("\"BAR=my test\""))
+		Expect(session.OutputToString()).To(ContainSubstring("USER=%%a"))
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "BAR=my test", "-e", "USER=%a", "--new", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("\"BAR=my test\""))
+		Expect(session.OutputToString()).To(ContainSubstring("USER=%%a"))
+
+		// Specify the environment variables without a value
+		os.Setenv("FOO1", "BAR1")
+		os.Setenv("FOO2", "BAR2")
+		os.Setenv("FOO3", "BAR3")
+		defer os.Unsetenv("FOO1")
+		defer os.Unsetenv("FOO2")
+		defer os.Unsetenv("FOO3")
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "FOO1", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR1"))
+		Expect(session.OutputToString()).NotTo(ContainSubstring("BAR2"))
+		Expect(session.OutputToString()).NotTo(ContainSubstring("BAR3"))
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "FOO*", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR1"))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR2"))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR3"))
+
+		session = podmanTest.Podman([]string{"generate", "systemd", "--env", "FOO*", "--new", "test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR1"))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR2"))
+		Expect(session.OutputToString()).To(ContainSubstring("BAR3"))
+	})
 })