Add generate systemd -e/--env option

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

Fixes: containers#15523

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

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", []string{}, "Set environment variables to the systemd unit files")
+	_ = systemdCmd.RegisterFlagCompletionFunc(envFlagName, completion.AutocompleteNone)
+
 	flags.SetNormalizeFunc(utils.TimeoutAliasFlags)
 }
 
@@ -141,6 +147,16 @@ func systemd(cmd *cobra.Command, args []string) error {
 	if cmd.Flags().Changed(stopTimeoutCompatFlagName) {
 		setStopTimeout++
 	}
+	if cmd.Flags().Changed(envFlagName) {
+		systemdOptions.AdditionalEnvVariables = make(map[string]string)
+
+		cliEnv, err := envLib.ParseSlice(envInput)
+		if err != nil {
+			return fmt.Errorf("error parsing environment variables: %w", err)
+		}
+
+		systemdOptions.AdditionalEnvVariables = envLib.Join(systemdOptions.AdditionalEnvVariables, cliEnv)
+	}
 	switch setStopTimeout {
 	case 1:
 		systemdOptions.StopTimeout = &stopTimeout

docs/source/markdown/podman-generate-systemd.1.md

@@ -44,6 +44,14 @@ 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.
+
+See [**Environment**](#environment) note below for precedence and examples.
+
 #### **--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.

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 map[string]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)

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:

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 - environment variables setted by -e/--env
+	AdditionalEnvVariables map[string]string
 }

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 map[string]string
 }
 
 // GenerateSystemdReport

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)