add as-current-user for fn run

kyaml/fn/runtime/container/container.go

@@ -5,6 +5,7 @@ package container
 
 import (
 	"fmt"
+	"os/user"
 
 	runtimeexec "sigs.k8s.io/kustomize/kyaml/fn/runtime/exec"
 	"sigs.k8s.io/kustomize/kyaml/fn/runtime/runtimeutil"
@@ -124,6 +125,8 @@ type Filter struct {
 	runtimeutil.ContainerSpec `json:",inline" yaml:",inline"`
 
 	Exec runtimeexec.Filter
+
+	UIDGID string
 }
 
 func (c Filter) String() string {
@@ -167,7 +170,7 @@ func (c *Filter) getCommand() (string, []string) {
 		"--network", string(network),
 
 		// added security options
-		"--user", c.User.String(),
+		"--user", c.UIDGID,
 		"--security-opt=no-new-privileges", // don't allow the user to escalate privileges
 		// note: don't make fs readonly because things like heredoc rely on writing tmp files
 	}
@@ -182,13 +185,28 @@ func (c *Filter) getCommand() (string, []string) {
 	return "docker", a
 }
 
-// NewContainer returns a new container filter
-func NewContainer(spec runtimeutil.ContainerSpec) Filter {
-	f := Filter{ContainerSpec: spec}
-	// default user is nobody
-	if f.ContainerSpec.User.IsEmpty() {
-		f.ContainerSpec.User = runtimeutil.UserNobody
+// getUIDGID will return "nobody" if asCurrentUser is false. Otherwise
+// return "uid:gid" according to current user who runs the command.
+func getUIDGID(asCurrentUser bool) (string, error) {
+	if !asCurrentUser {
+		return "nobody", nil
 	}
 
-	return f
+	u, err := user.Current()
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%s:%s", u.Uid, u.Gid), nil
+}
+
+// NewContainer returns a new container filter
+func NewContainer(spec runtimeutil.ContainerSpec, asCurrentUser bool) (Filter, error) {
+	f := Filter{ContainerSpec: spec}
+	u, err := getUIDGID(asCurrentUser)
+	if err != nil {
+		return f, err
+	}
+	f.UIDGID = u
+
+	return f, nil
 }

kyaml/fn/runtime/container/container_test.go

@@ -6,6 +6,7 @@ package container
 import (
 	"bytes"
 	"fmt"
+	"os/user"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -15,11 +16,16 @@ import (
 )
 
 func TestFilter_setupExec(t *testing.T) {
+	u, err := user.Current()
+	if err != nil {
+		t.Fatal(err)
+	}
 	var tests = []struct {
 		name           string
 		functionConfig string
 		expectedArgs   []string
-		instance       Filter
+		containerSpec  runtimeutil.ContainerSpec
+		asCurrentUser  bool
 	}{
 		{
 			name: "command",
@@ -36,12 +42,9 @@ metadata:
 				"--user", "nobody",
 				"--security-opt=no-new-privileges",
 			},
-			instance: NewContainer(
-				runtimeutil.ContainerSpec{
-					Image: "example.com:version",
-					User:  "nobody",
-				},
-			),
+			containerSpec: runtimeutil.ContainerSpec{
+				Image: "example.com:version",
+			},
 		},
 
 		{
@@ -63,9 +66,8 @@ metadata:
 				runtimeutil.ContainerSpec{
 					Image:   "example.com:version",
 					Network: true,
-					User:    "nobody",
 				},
-			),
+			},
 		},
 
 		{
@@ -87,21 +89,18 @@ metadata:
 				"--mount", fmt.Sprintf("type=%s,source=%s,target=%s,readonly", "volume", "myvol", "/local/"),
 				"--mount", fmt.Sprintf("type=%s,source=%s,target=%s,readonly", "tmpfs", "", "/local/"),
 			},
-			instance: NewContainer(
-				runtimeutil.ContainerSpec{
-					Image: "example.com:version",
-					StorageMounts: []runtimeutil.StorageMount{
-						{MountType: "bind", Src: "/mount/path", DstPath: "/local/"},
-						{MountType: "bind", Src: "/mount/pathrw", DstPath: "/localrw/", ReadWriteMode: true},
-						{MountType: "volume", Src: "myvol", DstPath: "/local/"},
-						{MountType: "tmpfs", Src: "", DstPath: "/local/"},
-					},
-					User: "nobody",
+			containerSpec: runtimeutil.ContainerSpec{
+				Image: "example.com:version",
+				StorageMounts: []runtimeutil.StorageMount{
+					{MountType: "bind", Src: "/mount/path", DstPath: "/local/"},
+					{MountType: "bind", Src: "/mount/pathrw", DstPath: "/localrw/", ReadWriteMode: true},
+					{MountType: "volume", Src: "myvol", DstPath: "/local/"},
+					{MountType: "tmpfs", Src: "", DstPath: "/local/"},
 				},
-			),
+			},
 		},
 		{
-			name: "root user",
+			name: "as current user",
 			functionConfig: `apiVersion: apps/v1
 kind: Deployment
 metadata:
@@ -112,15 +111,13 @@ metadata:
 				"--rm",
 				"-i", "-a", "STDIN", "-a", "STDOUT", "-a", "STDERR",
 				"--network", "none",
-				"--user", "root",
+				"--user", fmt.Sprintf("%s:%s", u.Uid, u.Gid),
 				"--security-opt=no-new-privileges",
 			},
-			instance: NewContainer(
-				runtimeutil.ContainerSpec{
-					Image: "example.com:version",
-					User:  "root",
-				},
-			),
+			containerSpec: runtimeutil.ContainerSpec{
+				Image: "example.com:version",
+			},
+			asCurrentUser: true,
 		},
 	}
 
@@ -131,18 +128,23 @@ metadata:
 			if !assert.NoError(t, err) {
 				t.FailNow()
 			}
-			tt.instance.Exec.FunctionConfig = cfg
-			tt.instance.Env = append(tt.instance.Env, "KYAML_TEST=FOO")
-			tt.instance.setupExec()
+
+			instance, err := NewContainer(tt.containerSpec, tt.asCurrentUser)
+			if err != nil {
+				t.Fatal(err)
+			}
+			instance.Exec.FunctionConfig = cfg
+			instance.Env = append(instance.Env, "KYAML_TEST=FOO")
+			instance.setupExec()
 
 			tt.expectedArgs = append(tt.expectedArgs,
-				runtimeutil.NewContainerEnvFromStringSlice(tt.instance.Env).GetDockerFlags()...)
-			tt.expectedArgs = append(tt.expectedArgs, tt.instance.Image)
+				runtimeutil.NewContainerEnvFromStringSlice(instance.Env).GetDockerFlags()...)
+			tt.expectedArgs = append(tt.expectedArgs, instance.Image)
 
-			if !assert.Equal(t, "docker", tt.instance.Exec.Path) {
+			if !assert.Equal(t, "docker", instance.Exec.Path) {
 				t.FailNow()
 			}
-			if !assert.Equal(t, tt.expectedArgs, tt.instance.Exec.Args) {
+			if !assert.Equal(t, tt.expectedArgs, instance.Exec.Args) {
 				t.FailNow()
 			}
 		})

kyaml/fn/runtime/runtimeutil/functiontypes.go

@@ -19,21 +19,6 @@ const (
 
 var functionAnnotationKeys = []string{FunctionAnnotationKey, oldFunctionAnnotationKey}
 
-// ContainerUser is a type for username/uid used in container
-type ContainerUser string
-
-func (u *ContainerUser) String() string {
-	return string(*u)
-}
-
-func (u *ContainerUser) IsEmpty() bool {
-	return string(*u) == ""
-}
-
-const (
-	UserNobody ContainerUser = "nobody"
-)
-
 // ContainerNetworkName is a type for network name used in container
 type ContainerNetworkName string
 
@@ -171,9 +156,6 @@ type ContainerSpec struct {
 	// Mounts are the storage or directories to mount into the container
 	StorageMounts []StorageMount `json:"mounts,omitempty" yaml:"mounts,omitempty"`
 
-	// User is the username/uid that application runs as in continer
-	User ContainerUser `json:"user,omitempty" yaml:"user,omitempty"`
-
 	// Env is a slice of env string that will be exposed to container
 	Env []string `json:"envs,omitempty" yaml:"envs,omitempty"`
 }

kyaml/runfn/runfn.go

@@ -85,8 +85,9 @@ type RunFns struct {
 	functionFilterProvider func(
 		filter runtimeutil.FunctionSpec, api *yaml.RNode) (kio.Filter, error)
 
-	// User username used to run the application in container,
-	User runtimeutil.ContainerUser
+	// AsCurrentUser is a boolean to indicate whether docker container should use
+	// the uid and gid that run the command
+	AsCurrentUser bool
 
 	// Env contains environment variables that will be exported to container
 	Env []string
@@ -299,10 +300,7 @@ func (r RunFns) getFunctionFilters(global bool, fns ...*yaml.RNode) (
 			// TODO(eddiezane): Provide error info about which function needs the network
 			return fltrs, errors.Errorf("network required but not enabled with --network")
 		}
-		// command line username and envs has higher priority
-		if !r.User.IsEmpty() {
-			spec.Container.User = r.User
-		}
+		// merge envs from imperative and declarative
 		spec.Container.Env = r.mergeContainerEnv(spec.Container.Env)
 
 		c, err := r.functionFilterProvider(*spec, api)
@@ -407,13 +405,18 @@ func (r *RunFns) ffp(spec runtimeutil.FunctionSpec, api *yaml.RNode) (kio.Filter
 	}
 	if !r.DisableContainers && spec.Container.Image != "" {
 		// TODO: Add a test for this behavior
-		c := container.NewContainer(runtimeutil.ContainerSpec{
-			Image:         spec.Container.Image,
-			Network:       spec.Container.Network,
-			StorageMounts: r.StorageMounts,
-			User:          spec.Container.User,
-			Env:           spec.Container.Env,
-		})
+		c, err := container.NewContainer(
+			runtimeutil.ContainerSpec{
+				Image:         spec.Container.Image,
+				Network:       spec.Container.Network,
+				StorageMounts: r.StorageMounts,
+				Env:           spec.Container.Env,
+			},
+			r.AsCurrentUser,
+		)
+		if err != nil {
+			return nil, err
+		}
 		cf := &c
 		cf.Exec.FunctionConfig = api
 		cf.Exec.GlobalScope = r.GlobalScope

kyaml/runfn/runfn_test.go

@@ -60,7 +60,10 @@ kind:
 		return
 	}
 	filter, _ := instance.functionFilterProvider(spec, api)
-	c := container.NewContainer(runtimeutil.ContainerSpec{Image: "example.com:version"})
+	c, err := container.NewContainer(runtimeutil.ContainerSpec{Image: "example.com:version"}, false)
+	if err != nil {
+		t.Fatal(err)
+	}
 	cf := &c
 	cf.Exec.FunctionConfig = api
 	assert.Equal(t, cf, filter)
@@ -91,7 +94,10 @@ kind:
 		return
 	}
 	filter, _ := instance.functionFilterProvider(spec, api)
-	c := container.NewContainer(runtimeutil.ContainerSpec{Image: "example.com:version"})
+	c, err := container.NewContainer(runtimeutil.ContainerSpec{Image: "example.com:version"}, false)
+	if err != nil {
+		t.Fatal(err)
+	}
 	cf := &c
 	cf.Exec.FunctionConfig = api
 	cf.Exec.GlobalScope = true