Implement machine provider selection

GetSystemDefaultProvider reworked to fetch provider value from
the config file.

Additional environment variable CONTAINERS_MACHINE_PROVIDER is
supported to override the config for testing purposes.

Signed-off-by: Arthur Sengileyev <arthur.sengileyev@gmail.com>

cmd/podman/machine/info.go

@@ -101,7 +101,10 @@ func hostInfo() (*entities.MachineHostInfo, error) {
 	host.Arch = runtime.GOARCH
 	host.OS = runtime.GOOS
 
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return nil, err
+	}
 	var listOpts machine.ListOptions
 	listResponse, err := provider.List(listOpts)
 	if err != nil {

cmd/podman/machine/init.go

@@ -30,7 +30,6 @@ var (
 	initOptionalFlags  = InitOptionalFlags{}
 	defaultMachineName = machine.DefaultMachineName
 	now                bool
-	defaultProvider    = GetSystemDefaultProvider()
 )
 
 // Flags which have a meaning when unspecified that differs from the flag default
@@ -129,7 +128,10 @@ func initMachine(cmd *cobra.Command, args []string) error {
 		vm  machine.VM
 	)
 
-	provider := defaultProvider
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	initOpts.Name = defaultMachineName
 	if len(args) > 0 {
 		if len(args[0]) > maxMachineNameSize {

cmd/podman/machine/inspect.go

@@ -51,7 +51,10 @@ func inspect(cmd *cobra.Command, args []string) error {
 		args = append(args, defaultMachineName)
 	}
 	vms := make([]machine.InspectInfo, 0, len(args))
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	for _, vmName := range args {
 		vm, err := provider.LoadVMByName(vmName)
 		if err != nil {

cmd/podman/machine/list.go

@@ -66,7 +66,10 @@ func list(cmd *cobra.Command, args []string) error {
 		err          error
 	)
 
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	listResponse, err = provider.List(opts)
 	if err != nil {
 		return fmt.Errorf("listing vms: %w", err)

cmd/podman/machine/machine.go

@@ -64,7 +64,10 @@ func autocompleteMachine(cmd *cobra.Command, args []string, toComplete string) (
 
 func getMachines(toComplete string) ([]string, cobra.ShellCompDirective) {
 	suggestions := []string{}
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return nil, cobra.ShellCompDirectiveNoFileComp
+	}
 	machines, err := provider.List(machine.ListOptions{})
 	if err != nil {
 		cobra.CompErrorln(err.Error())

cmd/podman/machine/os/manager.go

@@ -48,7 +48,10 @@ func machineOSManager(opts ManagerOpts) (pkgOS.Manager, error) {
 	if opts.VMName == "" {
 		vmName = pkgMachine.DefaultMachineName
 	}
-	provider := machine.GetSystemDefaultProvider()
+	provider, err := machine.GetSystemProvider()
+	if err != nil {
+		return nil, err
+	}
 	vm, err := provider.LoadVMByName(vmName)
 	if err != nil {
 		return nil, err

cmd/podman/machine/platform.go

@@ -4,10 +4,34 @@
 package machine
 
 import (
+	"fmt"
+	"os"
+
+	"github.com/containers/common/pkg/config"
 	"github.com/containers/podman/v4/pkg/machine"
 	"github.com/containers/podman/v4/pkg/machine/qemu"
+	"github.com/sirupsen/logrus"
 )
 
-func GetSystemDefaultProvider() machine.VirtProvider {
-	return qemu.GetVirtualizationProvider()
+func GetSystemProvider() (machine.VirtProvider, error) {
+	cfg, err := config.Default()
+	if err != nil {
+		return nil, err
+	}
+	provider := cfg.Machine.Provider
+	if providerOverride, found := os.LookupEnv("CONTAINERS_MACHINE_PROVIDER"); found {
+		provider = providerOverride
+	}
+	resolvedVMType, err := machine.ParseVMType(provider, machine.QemuVirt)
+	if err != nil {
+		return nil, err
+	}
+
+	logrus.Debugf("Using Podman machine with `%s` virtualization provider", resolvedVMType.String())
+	switch resolvedVMType {
+	case machine.QemuVirt:
+		return qemu.GetVirtualizationProvider(), nil
+	default:
+		return nil, fmt.Errorf("unsupported virtualization provider: `%s`", resolvedVMType.String())
+	}
 }

cmd/podman/machine/platform_windows.go

@@ -1,19 +1,37 @@
 package machine
 
 import (
+	"fmt"
 	"os"
 
+	"github.com/containers/common/pkg/config"
 	"github.com/containers/podman/v4/pkg/machine"
 	"github.com/containers/podman/v4/pkg/machine/hyperv"
 	"github.com/containers/podman/v4/pkg/machine/wsl"
+	"github.com/sirupsen/logrus"
 )
 
-func GetSystemDefaultProvider() machine.VirtProvider {
-	// This is a work-around for default provider on windows while
-	// hyperv is one developer.
-	// TODO this needs to be changed back
-	if _, exists := os.LookupEnv("HYPERV"); exists {
-		return hyperv.GetVirtualizationProvider()
+func GetSystemProvider() (machine.VirtProvider, error) {
+	cfg, err := config.Default()
+	if err != nil {
+		return nil, err
+	}
+	provider := cfg.Machine.Provider
+	if providerOverride, found := os.LookupEnv("CONTAINERS_MACHINE_PROVIDER"); found {
+		provider = providerOverride
+	}
+	resolvedVMType, err := machine.ParseVMType(provider, machine.WSLVirt)
+	if err != nil {
+		return nil, err
+	}
+
+	logrus.Debugf("Using Podman machine with `%s` virtualization provider", resolvedVMType.String())
+	switch resolvedVMType {
+	case machine.WSLVirt:
+		return wsl.GetWSLProvider(), nil
+	case machine.HyperVVirt:
+		return hyperv.GetVirtualizationProvider(), nil
+	default:
+		return nil, fmt.Errorf("unsupported virtualization provider: `%s`", resolvedVMType.String())
 	}
-	return wsl.GetWSLProvider()
 }

cmd/podman/machine/rm.go

@@ -63,7 +63,10 @@ func rm(_ *cobra.Command, args []string) error {
 		vmName = args[0]
 	}
 
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	vm, err = provider.LoadVMByName(vmName)
 	if err != nil {
 		return err

cmd/podman/machine/set.go

@@ -89,7 +89,10 @@ func setMachine(cmd *cobra.Command, args []string) error {
 	if len(args) > 0 && len(args[0]) > 0 {
 		vmName = args[0]
 	}
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	vm, err = provider.LoadVMByName(vmName)
 	if err != nil {
 		return err

cmd/podman/machine/ssh.go

@@ -53,7 +53,10 @@ func ssh(cmd *cobra.Command, args []string) error {
 
 	// Set the VM to default
 	vmName := defaultMachineName
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 
 	// If len is greater than 0, it means we may have been
 	// provided the VM name.  If so, we check.  The VM name,

cmd/podman/machine/start.go

@@ -53,7 +53,11 @@ func start(_ *cobra.Command, args []string) error {
 		vmName = args[0]
 	}
 
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
+
 	vm, err = provider.LoadVMByName(vmName)
 	if err != nil {
 		return err

cmd/podman/machine/stop.go

@@ -42,7 +42,10 @@ func stop(cmd *cobra.Command, args []string) error {
 	if len(args) > 0 && len(args[0]) > 0 {
 		vmName = args[0]
 	}
-	provider := GetSystemDefaultProvider()
+	provider, err := GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	vm, err = provider.LoadVMByName(vmName)
 	if err != nil {
 		return err

cmd/podman/system/reset_machine.go

@@ -8,6 +8,9 @@ import (
 )
 
 func resetMachine() error {
-	provider := cmdMach.GetSystemDefaultProvider()
+	provider, err := cmdMach.GetSystemProvider()
+	if err != nil {
+		return err
+	}
 	return provider.RemoveAndCleanMachines()
 }

pkg/machine/config.go

@@ -10,6 +10,7 @@ import (
 	"net/url"
 	"os"
 	"path/filepath"
+	"strings"
 	"time"
 
 	"github.com/containers/storage/pkg/homedir"
@@ -413,3 +414,20 @@ const (
 	MachineLocal
 	DockerGlobal
 )
+
+func ParseVMType(input string, emptyFallback VMType) (VMType, error) {
+	switch strings.TrimSpace(strings.ToLower(input)) {
+	case "qemu":
+		return QemuVirt, nil
+	case "wsl":
+		return WSLVirt, nil
+	case "applehv":
+		return AppleHvVirt, nil
+	case "hyperv":
+		return HyperVVirt, nil
+	case "":
+		return emptyFallback, nil
+	default:
+		return QemuVirt, fmt.Errorf("unknown VMType `%s`", input)
+	}
+}