legacy: deprecate old NRI types

This commit adds deprecation comments to old types and adds a new method
that the runtime can use to retrieve configured plugins, so a
deprecation warning can be produced at runtime.

Signed-off-by: Samuel Karp <samuelkarp@google.com>
Signed-off-by: Chris Henzie <chrishenzie@google.com>

Author: samuelkarp

client.go

@@ -42,6 +42,8 @@ const (
 var appendPathOnce sync.Once
 
 // New nri client
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 func New() (*Client, error) {
 	conf, err := loadConfig(DefaultConfPath)
 	if err != nil {
@@ -60,12 +62,28 @@ func New() (*Client, error) {
 	}, nil
 }
 
+// Plugins returns a slice of the configured plugin names. This can be used by
+// the runtime to detect which plugins are configured.
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
+func (c *Client) Plugins() []string {
+	names := make([]string, 0)
+	for _, p := range c.conf.Plugins {
+		names = append(names, p.Type)
+	}
+	return names
+}
+
 // Client for calling nri plugins
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Client struct {
 	conf *types.ConfigList
 }
 
 // Sandbox information
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Sandbox struct {
 	// ID of the sandbox
 	ID string
@@ -82,6 +100,8 @@ type process interface {
 }
 
 // Task is a subset of containerd's Task interface.
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Task interface {
 	process
 
@@ -90,11 +110,15 @@ type Task interface {
 }
 
 // Invoke the ConfList of nri plugins
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 func (c *Client) Invoke(ctx context.Context, task Task, state types.State) ([]*types.Result, error) {
 	return c.InvokeWithSandbox(ctx, task, state, nil)
 }
 
 // InvokeWithSandbox invokes the ConfList of nri plugins
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 func (c *Client) InvokeWithSandbox(ctx context.Context, task Task, state types.State, sandbox *Sandbox) ([]*types.Result, error) {
 	if len(c.conf.Plugins) == 0 {
 		return nil, nil
@@ -129,7 +153,7 @@ func (c *Client) InvokeWithSandbox(ctx context.Context, task Task, state types.S
 	return r.Results, nil
 }
 
-func (c *Client) invokePlugin(ctx context.Context, name string, r *types.Request) (*types.Result, error) {
+func (c *Client) invokePlugin(ctx context.Context, name string, r *types.Request) (*types.Result, error) { //nolint:staticcheck
 	payload, err := json.Marshal(r)
 	if err != nil {
 		return nil, err
@@ -154,28 +178,28 @@ func (c *Client) invokePlugin(ctx context.Context, name string, r *types.Request
 			return nil, err
 		}
 	}
-	var result types.Result
+	var result types.Result //nolint:staticcheck
 	if err := json.Unmarshal(out, &result); err != nil {
 		return nil, fmt.Errorf("failed to unmarshal plugin output %s: %w", msg, err)
 	}
-	if result.Err() != nil {
-		return nil, result.Err()
+	if result.Err() != nil { //nolint:staticcheck
+		return nil, result.Err() //nolint:staticcheck
 	}
 	return &result, nil
 }
 
-func loadConfig(path string) (*types.ConfigList, error) {
+func loadConfig(path string) (*types.ConfigList, error) { //nolint:staticcheck
 	f, err := os.Open(path)
 	if err != nil {
 		// if we don't have a config list on disk, create a new one for use
 		if os.IsNotExist(err) {
-			return &types.ConfigList{
+			return &types.ConfigList{ //nolint:staticcheck
 				Version: Version,
 			}, nil
 		}
 		return nil, err
 	}
-	var c types.ConfigList
+	var c types.ConfigList //nolint:staticcheck
 	err = json.NewDecoder(f).Decode(&c)
 	f.Close()
 	if err != nil {
@@ -184,8 +208,8 @@ func loadConfig(path string) (*types.ConfigList, error) {
 	return &c, nil
 }
 
-func createSpec(spec *oci.Spec) (*types.Spec, error) {
-	s := types.Spec{
+func createSpec(spec *oci.Spec) (*types.Spec, error) { //nolint:staticcheck
+	s := types.Spec{ //nolint:staticcheck
 		Namespaces:  make(map[string]string),
 		Annotations: spec.Annotations,
 	}

skel/skel.go

@@ -30,13 +30,13 @@ type Plugin interface {
 	// Type or plugin name
 	Type() string
 	// Invoke the plugin
-	Invoke(context.Context, *types.Request) (*types.Result, error)
+	Invoke(context.Context, *types.Request) (*types.Result, error) //nolint:staticcheck
 }
 
 // Run the plugin from a main() function
 func Run(ctx context.Context, plugin Plugin) error {
 	enc := json.NewEncoder(os.Stdout)
-	var request types.Request
+	var request types.Request //nolint:staticcheck
 	if err := json.NewDecoder(os.Stdin).Decode(&request); err != nil {
 		return err
 	}
@@ -45,14 +45,14 @@ func Run(ctx context.Context, plugin Plugin) error {
 		result, err := plugin.Invoke(ctx, &request)
 		if err != nil {
 			// if the plugin sets ErrorMessage we ignore it
-			result = request.NewResult(plugin.Type())
+			result = request.NewResult(plugin.Type()) //nolint:staticcheck
 			result.Error = err.Error()
 		}
 		if err := enc.Encode(result); err != nil {
 			return fmt.Errorf("unable to encode plugin error to stdout: %w", err)
 		}
 	default:
-		result := request.NewResult(plugin.Type())
+		result := request.NewResult(plugin.Type()) //nolint:staticcheck
 		result.Error = fmt.Sprintf("invalid arg %s", os.Args[1])
 		if err := enc.Encode(result); err != nil {
 			return fmt.Errorf("unable to encode invalid parameter error to stdout: %w", err)

types/v1/types.go

@@ -22,6 +22,8 @@ import (
 )
 
 // Plugin type and configuration
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Plugin struct {
 	// Type of plugin
 	Type string `json:"type"`
@@ -32,6 +34,8 @@ type Plugin struct {
 // ConfigList for the global configuration of NRI
 //
 // Normally located at /etc/nri/conf.json
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type ConfigList struct {
 	// Version of the list
 	Version string `json:"version"`
@@ -40,6 +44,8 @@ type ConfigList struct {
 }
 
 // Spec for the container being processed
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Spec struct {
 	// Resources struct from the OCI specification
 	//
@@ -54,6 +60,8 @@ type Spec struct {
 }
 
 // State of the request
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type State string
 
 const (
@@ -70,6 +78,8 @@ const (
 )
 
 // Request for a plugin invocation
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Request struct {
 	// Conf specific for the plugin
 	Conf json.RawMessage `json:"conf,omitempty"`
@@ -98,11 +108,15 @@ type Request struct {
 }
 
 // IsSandbox returns true if the request is for a sandbox
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 func (r *Request) IsSandbox() bool {
 	return r.ID == r.SandboxID
 }
 
 // NewResult returns a result from the original request
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 func (r *Request) NewResult(plugin string) *Result {
 	return &Result{
 		Plugin:   plugin,
@@ -112,6 +126,8 @@ func (r *Request) NewResult(plugin string) *Result {
 }
 
 // Result of the plugin invocation
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 type Result struct {
 	// Plugin name that populated the result
 	Plugin string `json:"plugin"`
@@ -124,6 +140,8 @@ type Result struct {
 }
 
 // Err creates an Error object if ErrorMessage is populated
+//
+// Deprecated: NRI 0.1.0-style plugins should only be used through the v010-adapter plugin
 func (r *Result) Err() error {
 	if r.Error != "" {
 		return errors.New(r.Error)