ctr: print deprecation warnings on every invocation

AkihiroSuda · AkihiroSuda · commit eaebe23de407 · 2024-02-14T15:26:28.000+09:00
Print deprecation warnings on any ctr command, as users won't notice the deprecations until we actually remove the deprecated features. The warnings can be suppressed by setting `CONTAINERD_SUPPRESS_DEPRECATION_WARNINGS=1`. Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp> (cherry picked from commit 468bee9) (cherry-pick was not clean) Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
diff --git a/cmd/ctr/commands/client.go b/cmd/ctr/commands/client.go
@@ -18,11 +18,14 @@ package commands
 
 import (
 	gocontext "context"
+	"os"
+	"strconv"
 
 	"github.com/containerd/containerd"
 	"github.com/containerd/containerd/log"
 	"github.com/containerd/containerd/namespaces"
 	"github.com/containerd/containerd/pkg/epoch"
+	ptypes "github.com/containerd/containerd/protobuf/types"
 	"github.com/urfave/cli"
 )
 
@@ -62,5 +65,22 @@ func NewClient(context *cli.Context, opts ...containerd.ClientOpt) (*containerd.
 		return nil, nil, nil, err
 	}
 	ctx, cancel := AppContext(context)
+	var suppressDeprecationWarnings bool
+	if s := os.Getenv("CONTAINERD_SUPPRESS_DEPRECATION_WARNINGS"); s != "" {
+		suppressDeprecationWarnings, err = strconv.ParseBool(s)
+		if err != nil {
+			log.L.WithError(err).Warn("Failed to parse CONTAINERD_SUPPRESS_DEPRECATION_WARNINGS=" + s)
+		}
+	}
+	if !suppressDeprecationWarnings {
+		resp, err := client.IntrospectionService().Server(ctx, &ptypes.Empty{})
+		if err != nil {
+			log.L.WithError(err).Warn("Failed to check deprecations")
+		} else {
+			for _, d := range resp.Deprecations {
+				log.L.Warn("DEPRECATION: " + d.Message)
+			}
+		}
+	}
 	return client, ctx, cancel, nil
 }
diff --git a/cmd/ctr/commands/deprecations/deprecations.go b/cmd/ctr/commands/deprecations/deprecations.go
@@ -47,6 +47,9 @@ var listCommand = cli.Command{
 		},
 	},
 	Action: func(context *cli.Context) error {
+		// Suppress automatic warnings, since we print the warnings by ourselves.
+		os.Setenv("CONTAINERD_SUPPRESS_DEPRECATION_WARNINGS", "1")
+
 		client, ctx, cancel, err := commands.NewClient(context)
 		if err != nil {
 			return err
