oci: introduce WithSpecFromFile combinator

We introduce a WithSpecFromFile option combinator to allow creation
simpler creation of OCI specs from a file name. Often used as the first
option in a `SpecOpts` slice, it simplifies choosing between a local
file and the built-in default.

The code in `ctr run` has been updated to use the new option, with out
changing the order of operations or functionality present there.

Signed-off-by: Stephen Day <stephen.day@getcruise.com>
This commit is contained in:
Stephen Day 2018-07-19 12:38:00 -07:00
parent c8017d0275
commit 2a1bd7414b
No known key found for this signature in database
GPG Key ID: 31230539849BCE67
9 changed files with 162 additions and 44 deletions

View File

@ -19,9 +19,7 @@ package run
import (
gocontext "context"
"encoding/csv"
"encoding/json"
"fmt"
"io/ioutil"
"strings"
"github.com/containerd/console"
@ -37,17 +35,6 @@ import (
"github.com/urfave/cli"
)
func loadSpec(path string, s *specs.Spec) error {
raw, err := ioutil.ReadFile(path)
if err != nil {
return errors.New("cannot load spec config file")
}
if err := json.Unmarshal(raw, s); err != nil {
return errors.Errorf("decoding spec config file failed, current supported OCI runtime-spec : v%s", specs.Version)
}
return nil
}
func withMounts(context *cli.Context) oci.SpecOpts {
return func(ctx gocontext.Context, client oci.Client, container *containers.Container, s *specs.Spec) error {
mounts := make([]specs.Mount, 0)

View File

@ -52,6 +52,13 @@ func NewContainer(ctx gocontext.Context, client *containerd.Client, context *cli
cOpts []containerd.NewContainerOpts
spec containerd.NewContainerOpts
)
if context.IsSet("config") {
opts = append(opts, oci.WithSpecFromFile(context.String("config")))
} else {
opts = append(opts, oci.WithDefaultSpec())
}
opts = append(opts, oci.WithEnv(context.StringSlice("env")))
opts = append(opts, withMounts(context))
cOpts = append(cOpts, containerd.WithContainerLabels(commands.LabelArgs(context.StringSlice("label"))))
@ -117,15 +124,10 @@ func NewContainer(ctx gocontext.Context, client *containerd.Client, context *cli
if context.IsSet("gpus") {
opts = append(opts, nvidia.WithGPUs(nvidia.WithDevices(context.Int("gpus")), nvidia.WithAllCapabilities))
}
if context.IsSet("config") {
var s specs.Spec
if err := loadSpec(context.String("config"), &s); err != nil {
return nil, err
}
spec = containerd.WithSpec(&s, opts...)
} else {
spec = containerd.WithNewSpec(opts...)
}
var s specs.Spec
spec = containerd.WithSpec(&s, opts...)
cOpts = append(cOpts, spec)
// oci.WithImageConfig (WithUsername, WithUserID) depends on rootfs snapshot for resolving /etc/passwd.

View File

@ -63,6 +63,13 @@ func NewContainer(ctx gocontext.Context, client *containerd.Client, context *cli
cOpts []containerd.NewContainerOpts
spec containerd.NewContainerOpts
)
if context.IsSet("config") {
opts = append(opts, oci.WithSpecFromFile(context.String("config")))
} else {
opts = append(opts, oci.WithDefaultSpec())
}
opts = append(opts, oci.WithImageConfig(image))
opts = append(opts, oci.WithEnv(context.StringSlice("env")))
opts = append(opts, withMounts(context))
@ -74,15 +81,8 @@ func NewContainer(ctx gocontext.Context, client *containerd.Client, context *cli
opts = append(opts, oci.WithProcessCwd(cwd))
}
if context.IsSet("config") {
var s specs.Spec
if err := loadSpec(context.String("config"), &s); err != nil {
return nil, err
}
spec = containerd.WithSpec(&s, opts...)
} else {
spec = containerd.WithNewSpec(opts...)
}
var s specs.Spec
spec = containerd.WithSpec(&s, opts...)
cOpts = append(cOpts, containerd.WithContainerLabels(commands.LabelArgs(context.StringSlice("label"))))
cOpts = append(cOpts, containerd.WithImage(image))

View File

@ -197,11 +197,10 @@ func WithNewSpec(opts ...oci.SpecOpts) NewContainerOpts {
// WithSpec sets the provided spec on the container
func WithSpec(s *oci.Spec, opts ...oci.SpecOpts) NewContainerOpts {
return func(ctx context.Context, client *Client, c *containers.Container) error {
for _, o := range opts {
if err := o(ctx, client, c, s); err != nil {
return err
}
if err := oci.ApplyOpts(ctx, client, c, s, opts...); err != nil {
return err
}
var err error
c.Spec, err = typeurl.MarshalAny(s)
return err

View File

@ -34,10 +34,23 @@ func GenerateSpec(ctx context.Context, client Client, c *containers.Container, o
if err != nil {
return nil, err
}
return s, ApplyOpts(ctx, client, c, s, opts...)
}
// ApplyOpts applys the options to the given spec, injecting data from the
// context, client and container instance.
func ApplyOpts(ctx context.Context, client Client, c *containers.Container, s *Spec, opts ...SpecOpts) error {
for _, o := range opts {
if err := o(ctx, client, c, s); err != nil {
return nil, err
return err
}
}
return s, nil
return nil
}
func createDefaultSpec(ctx context.Context, id string) (*Spec, error) {
var s Spec
return &s, populateDefaultSpec(ctx, &s, id)
}

View File

@ -18,10 +18,13 @@ package oci
import (
"context"
"encoding/json"
"io/ioutil"
"strings"
"github.com/containerd/containerd/containers"
specs "github.com/opencontainers/runtime-spec/specs-go"
"github.com/pkg/errors"
)
// SpecOpts sets spec specific information to a newly generated OCI spec
@ -46,6 +49,38 @@ func setProcess(s *Spec) {
}
}
// WithDefaultSpec returns a SpecOpts that will populate the spec with default
// values.
//
// Use as the first option to clear the spec, then apply options afterwards.
func WithDefaultSpec() SpecOpts {
return func(ctx context.Context, _ Client, c *containers.Container, s *Spec) error {
return populateDefaultSpec(ctx, s, c.ID)
}
}
// WithSpecFromBytes loads the the spec from the provided byte slice.
func WithSpecFromBytes(p []byte) SpecOpts {
return func(_ context.Context, _ Client, _ *containers.Container, s *Spec) error {
*s = Spec{} // make sure spec is cleared.
if err := json.Unmarshal(p, s); err != nil {
return errors.Wrapf(err, "decoding spec config file failed, current supported OCI runtime-spec : v%s", specs.Version)
}
return nil
}
}
// WithSpecFromFile loads the specification from the provided filename.
func WithSpecFromFile(filename string) SpecOpts {
return func(ctx context.Context, c Client, container *containers.Container, s *Spec) error {
p, err := ioutil.ReadFile(filename)
if err != nil {
return errors.Wrap(err, "cannot load spec config file")
}
return WithSpecFromBytes(p)(ctx, c, container, s)
}
}
// WithProcessArgs replaces the args on the generated spec
func WithProcessArgs(args ...string) SpecOpts {
return func(_ context.Context, _ Client, _ *containers.Container, s *Spec) error {

View File

@ -17,8 +17,16 @@
package oci
import (
"context"
"encoding/json"
"io/ioutil"
"log"
"os"
"reflect"
"testing"
"github.com/containerd/containerd/containers"
"github.com/containerd/containerd/namespaces"
specs "github.com/opencontainers/runtime-spec/specs-go"
)
@ -87,3 +95,75 @@ func TestWithMounts(t *testing.T) {
t.Fatal("invaid mount")
}
}
func TestWithDefaultSpec(t *testing.T) {
t.Parallel()
var (
s Spec
c = containers.Container{ID: "TestWithDefaultSpec"}
ctx = namespaces.WithNamespace(context.Background(), "test")
)
if err := ApplyOpts(ctx, nil, &c, &s, WithDefaultSpec()); err != nil {
t.Fatal(err)
}
expected, err := createDefaultSpec(ctx, c.ID)
if err != nil {
t.Fatal(err)
}
if reflect.DeepEqual(s, Spec{}) {
t.Fatalf("spec should not be empty")
}
if !reflect.DeepEqual(&s, expected) {
t.Fatalf("spec from option differs from default: \n%#v != \n%#v", &s, expected)
}
}
func TestWithSpecFromFile(t *testing.T) {
t.Parallel()
var (
s Spec
c = containers.Container{ID: "TestWithDefaultSpec"}
ctx = namespaces.WithNamespace(context.Background(), "test")
)
fp, err := ioutil.TempFile("", "testwithdefaultspec.json")
if err != nil {
t.Fatal(err)
}
defer fp.Close()
defer func() {
if err := os.Remove(fp.Name()); err != nil {
log.Printf("failed to remove tempfile %v: %v", fp.Name(), err)
}
}()
expected, err := GenerateSpec(ctx, nil, &c)
if err != nil {
t.Fatal(err)
}
p, err := json.Marshal(expected)
if err != nil {
t.Fatal(err)
}
if _, err := fp.Write(p); err != nil {
t.Fatal(err)
}
if err := ApplyOpts(ctx, nil, &c, &s, WithSpecFromFile(fp.Name())); err != nil {
t.Fatal(err)
}
if reflect.DeepEqual(s, Spec{}) {
t.Fatalf("spec should not be empty")
}
if !reflect.DeepEqual(&s, expected) {
t.Fatalf("spec from option differs from default: \n%#v != \n%#v", &s, expected)
}
}

View File

@ -76,12 +76,13 @@ func defaultNamespaces() []specs.LinuxNamespace {
}
}
func createDefaultSpec(ctx context.Context, id string) (*Spec, error) {
func populateDefaultSpec(ctx context.Context, s *Spec, id string) error {
ns, err := namespaces.NamespaceRequired(ctx)
if err != nil {
return nil, err
return err
}
s := &Spec{
*s = Spec{
Version: specs.Version,
Root: &specs.Root{
Path: defaultRootfsPath,
@ -183,5 +184,5 @@ func createDefaultSpec(ctx context.Context, id string) (*Spec, error) {
Namespaces: defaultNamespaces(),
},
}
return s, nil
return nil
}

View File

@ -22,8 +22,8 @@ import (
specs "github.com/opencontainers/runtime-spec/specs-go"
)
func createDefaultSpec(ctx context.Context, id string) (*Spec, error) {
return &Spec{
func populateDefaultSpec(ctx context.Context, s *Spec, id string) error {
*s = Spec{
Version: specs.Version,
Root: &specs.Root{},
Process: &specs.Process{
@ -39,5 +39,6 @@ func createDefaultSpec(ctx context.Context, id string) (*Spec, error) {
AllowUnqualifiedDNSQuery: true,
},
},
}, nil
}
return nil
}