Add service endpoint

add service endpoint for the new API.  Also supports the varlink
implementation.

Signed-off-by: baude <bbaude@redhat.com>

Refactor to allow developer more control of API server

* Add api.NewServerWithSettings() to create an API server with custom
  settings
* Add api.ListenUnix() to create a UDS net.Listener and setup UDS

Signed-off-by: Jhon Honce <jhonce@redhat.com>
Signed-off-by: baude <bbaude@redhat.com>

More service completion

Add podman service command that allows users to run either a RESTful or
varlink protocol API service.

Addition of docs and RESTful listening.

Signed-off-by: baude <bbaude@redhat.com>
Signed-off-by: Brent Baude <bbaude@redhat.com>

5 files changed, 175 insertions, 1 deletions

diff --git a/cmd/podman/cliconfig/config.go b/cmd/podman/cliconfig/config.go
index b261599e6..6bc8aa4a3 100644
--- a/cmd/podman/cliconfig/config.go
+++ b/cmd/podman/cliconfig/config.go
@@ -599,6 +599,12 @@ type VarlinkValues struct {
 	Timeout int64
 }
 
+type ServiceValues struct {
+	PodmanCommand
+	Varlink bool
+	Timeout int64
+}
+
 type SetTrustValues struct {
 	PodmanCommand
 	PolicyPath  string
diff --git a/cmd/podman/commands.go b/cmd/podman/commands.go
index 31f1b3ba4..ebd7aeb0c 100644
--- a/cmd/podman/commands.go
+++ b/cmd/podman/commands.go
@@ -26,6 +26,9 @@ func getMainCommands() []*cobra.Command {
 	if len(_varlinkCommand.Use) > 0 {
 		rootCommands = append(rootCommands, _varlinkCommand)
 	}
+	if len(_serviceCommand.Use) > 0 {
+		rootCommands = append(rootCommands, _serviceCommand)
+	}
 	return rootCommands
 }
 
diff --git a/cmd/podman/service.go b/cmd/podman/service.go
new file mode 100644
index 000000000..6e2b4a366
--- /dev/null
+++ b/cmd/podman/service.go
@@ -0,0 +1,154 @@
+// +build varlink,!remoteclient
+
+package main
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/containers/libpod/cmd/podman/cliconfig"
+	"github.com/containers/libpod/cmd/podman/libpodruntime"
+	iopodman "github.com/containers/libpod/cmd/podman/varlink"
+	"github.com/containers/libpod/libpod"
+	"github.com/containers/libpod/pkg/adapter"
+	api "github.com/containers/libpod/pkg/api/server"
+	"github.com/containers/libpod/pkg/rootless"
+	"github.com/containers/libpod/pkg/util"
+	"github.com/containers/libpod/pkg/varlinkapi"
+	"github.com/containers/libpod/version"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"github.com/varlink/go/varlink"
+)
+
+var (
+	serviceCommand     cliconfig.ServiceValues
+	serviceDescription = `Run an API service
+
+Enable a listening service for API access to Podman commands.
+`
+
+	_serviceCommand = &cobra.Command{
+		Use:   "service [flags] [URI]",
+		Short: "Run API service",
+		Long:  serviceDescription,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			serviceCommand.InputArgs = args
+			serviceCommand.GlobalFlags = MainGlobalOpts
+			return serviceCmd(&serviceCommand)
+		},
+	}
+)
+
+func init() {
+	serviceCommand.Command = _serviceCommand
+	serviceCommand.SetHelpTemplate(HelpTemplate())
+	serviceCommand.SetUsageTemplate(UsageTemplate())
+	flags := serviceCommand.Flags()
+	flags.Int64VarP(&serviceCommand.Timeout, "timeout", "t", 1000, "Time until the service session expires in milliseconds.  Use 0 to disable the timeout")
+	flags.BoolVar(&serviceCommand.Varlink, "varlink", false, "Use legacy varlink service instead of REST")
+}
+
+func serviceCmd(c *cliconfig.ServiceValues) error {
+	// For V2, default to the REST socket
+	apiURI := adapter.DefaultAPIAddress
+	if c.Varlink {
+		apiURI = adapter.DefaultVarlinkAddress
+	}
+
+	if rootless.IsRootless() {
+		xdg, err := util.GetRuntimeDir()
+		if err != nil {
+			return err
+		}
+		socketName := "podman.sock"
+		if c.Varlink {
+			socketName = "io.podman"
+		}
+		socketDir := filepath.Join(xdg, "podman", socketName)
+		if _, err := os.Stat(filepath.Dir(socketDir)); err != nil {
+			if os.IsNotExist(err) {
+				if err := os.Mkdir(filepath.Dir(socketDir), 0755); err != nil {
+					return err
+				}
+			} else {
+				return err
+			}
+		}
+		apiURI = fmt.Sprintf("unix:%s", socketDir)
+	}
+
+	if len(c.InputArgs) > 0 {
+		apiURI = c.InputArgs[0]
+	}
+
+	logrus.Infof("using API endpoint: %s", apiURI)
+
+	// Create a single runtime api consumption
+	runtime, err := libpodruntime.GetRuntimeDisableFDs(getContext(), &c.PodmanCommand)
+	if err != nil {
+		return errors.Wrapf(err, "error creating libpod runtime")
+	}
+	defer runtime.DeferredShutdown(false)
+
+	timeout := time.Duration(c.Timeout) * time.Millisecond
+	if c.Varlink {
+		return runVarlink(runtime, apiURI, timeout, c)
+	}
+	return runREST(runtime, apiURI, timeout)
+}
+
+func runREST(r *libpod.Runtime, uri string, timeout time.Duration) error {
+	logrus.Warn("This function is EXPERIMENTAL")
+	fmt.Println("This function is EXPERIMENTAL.")
+	fields := strings.Split(uri, ":")
+	if len(fields) == 1 {
+		return errors.Errorf("%s is an invalid socket destination", uri)
+	}
+	address := strings.Join(fields[1:], ":")
+	l, err := net.Listen(fields[0], address)
+	if err != nil {
+		return errors.Wrapf(err, "unable to create socket %s", uri)
+	}
+	server, err := api.NewServerWithSettings(r, timeout, &l)
+	if err != nil {
+		return err
+	}
+	return server.Serve()
+}
+
+func runVarlink(r *libpod.Runtime, uri string, timeout time.Duration, c *cliconfig.ServiceValues) error {
+	var varlinkInterfaces = []*iopodman.VarlinkInterface{varlinkapi.New(&c.PodmanCommand, r)}
+	service, err := varlink.NewService(
+		"Atomic",
+		"podman",
+		version.Version,
+		"https://github.com/containers/libpod",
+	)
+	if err != nil {
+		return errors.Wrapf(err, "unable to create new varlink service")
+	}
+
+	for _, i := range varlinkInterfaces {
+		if err := service.RegisterInterface(i); err != nil {
+			return errors.Errorf("unable to register varlink interface %v", i)
+		}
+	}
+
+	// Run the varlink server at the given address
+	if err = service.Listen(uri, timeout); err != nil {
+		switch err.(type) {
+		case varlink.ServiceTimeoutError:
+			logrus.Infof("varlink service expired (use --timeout to increase session time beyond %d ms, 0 means never timeout)", timeout.String())
+			return nil
+		default:
+			return errors.Wrapf(err, "unable to start varlink service")
+		}
+	}
+	return nil
+}
diff --git a/cmd/podman/service_dummy.go b/cmd/podman/service_dummy.go
new file mode 100644
index 000000000..a774c34de
--- /dev/null
+++ b/cmd/podman/service_dummy.go
@@ -0,0 +1,11 @@
+// +build !varlink
+
+package main
+
+import "github.com/spf13/cobra"
+
+var (
+	_serviceCommand = &cobra.Command{
+		Use: "",
+	}
+)
diff --git a/cmd/podman/varlink.go b/cmd/podman/varlink.go
index cd21e3574..047d94fc2 100644
--- a/cmd/podman/varlink.go
+++ b/cmd/podman/varlink.go
@@ -51,7 +51,7 @@ func init() {
 }
 
 func varlinkCmd(c *cliconfig.VarlinkValues) error {
-	varlinkURI := adapter.DefaultAddress
+	varlinkURI := adapter.DefaultVarlinkAddress
 	if rootless.IsRootless() {
 		xdg, err := util.GetRuntimeDir()
 		if err != nil {