server: add ability to record config deprecations

samuelkarp · samuelkarp · commit fa5f3c91a946 · 2023-10-31T17:11:12.000-07:00
Signed-off-by: Samuel Karp <samuelkarp@google.com> (cherry picked from commit 260e71a) Signed-off-by: Samuel Karp <samuelkarp@google.com>
diff --git a/plugin/context.go b/plugin/context.go
@@ -21,9 +21,10 @@ import (
 	"fmt"
 	"path/filepath"
 
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+
 	"github.com/containerd/containerd/errdefs"
 	"github.com/containerd/containerd/events/exchange"
-	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
 // InitContext is used for plugin initialization
@@ -133,6 +134,19 @@ func (ps *Set) Get(t Type) (interface{}, error) {
 	return nil, fmt.Errorf("no plugins registered for %s: %w", t, errdefs.ErrNotFound)
 }
 
+// GetByID returns the plugin of the given type and ID
+func (ps *Set) GetByID(t Type, id string) (*Plugin, error) {
+	typSet, ok := ps.byTypeAndID[t]
+	if !ok || len(typSet) == 0 {
+		return nil, fmt.Errorf("no plugins registered for %s: %w", t, errdefs.ErrNotFound)
+	}
+	p, ok := typSet[id]
+	if !ok {
+		return nil, fmt.Errorf("no plugins registered for %s %q: %w", t, id, errdefs.ErrNotFound)
+	}
+	return p, nil
+}
+
 // GetAll returns all initialized plugins
 func (ps *Set) GetAll() []*Plugin {
 	return ps.ordered
diff --git a/services/server/server.go b/services/server/server.go
@@ -48,6 +48,7 @@ import (
 	"github.com/containerd/containerd/pkg/timeout"
 	"github.com/containerd/containerd/plugin"
 	srvconfig "github.com/containerd/containerd/services/server/config"
+	"github.com/containerd/containerd/services/warning"
 	ssproxy "github.com/containerd/containerd/snapshots/proxy"
 	"github.com/containerd/containerd/sys"
 	"github.com/containerd/ttrpc"
@@ -295,9 +296,33 @@ func New(ctx context.Context, config *srvconfig.Config) (*Server, error) {
 			return nil, err
 		}
 	}
+
+	recordConfigDeprecations(ctx, config, initialized)
 	return s, nil
 }
 
+// recordConfigDeprecations attempts to record use of any deprecated config field.  Failures are logged and ignored.
+func recordConfigDeprecations(ctx context.Context, config *srvconfig.Config, set *plugin.Set) {
+	// record any detected deprecations without blocking server startup
+	plugin, err := set.GetByID(plugin.WarningPlugin, plugin.DeprecationsPlugin)
+	if err != nil {
+		log.G(ctx).WithError(err).Warn("failed to load warning service to record deprecations")
+		return
+	}
+	instance, err := plugin.Instance()
+	if err != nil {
+		log.G(ctx).WithError(err).Warn("failed to load warning service to record deprecations")
+		return
+	}
+	warn, ok := instance.(warning.Service)
+	if !ok {
+		log.G(ctx).WithError(err).Warn("failed to load warning service to record deprecations, unexpected plugin type")
+		return
+	}
+
+	_ = warn // TODO(samuelkarp): placeholder for future use
+}
+
 // Server is the containerd main daemon
 type Server struct {
 	grpcServer  *grpc.Server
