cli-plugins: remove docker.cli specific otel attributes after usage

Remove the `docker.cli` prefixed attributes from
`OTEL_RESOURCE_ATTRIBUTES` after the telemetry provider has been created
within a plugin. This prevents accidentally sending the attributes to
something downstream for the user.

This also fixes an issue with compose where the self-injected `OTEL_RESOURCE_ATTRIBUTES`
would override an existing attribute in the environment file because the
"user environment" overrode the environment file, but the "user
environment" was created by the `docker` tool rather than by the user's
environment.

When `OTEL_RESOURCE_ATTRIBUTES` is empty after pruning, the environment
variable is unset.

Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>

cli-plugins/manager/cobra.go

@@ -107,7 +107,7 @@ func AddPluginCommandStubs(dockerCli command.Cli, rootCmd *cobra.Command) (err e
 }
 
 const (
-	dockerCliAttributePrefix = attribute.Key("docker.cli")
+	dockerCliAttributePrefix = command.DockerCliAttributePrefix
 
 	cobraCommandPath = attribute.Key("cobra.command_path")
 )
@@ -126,7 +126,7 @@ func getPluginResourceAttributes(cmd *cobra.Command, plugin Plugin) attribute.Se
 	for iter := attrSet.Iter(); iter.Next(); {
 		attr := iter.Attribute()
 		kvs = append(kvs, attribute.KeyValue{
-			Key:   dockerCliAttributePrefix + "." + attr.Key,
+			Key:   dockerCliAttributePrefix + attr.Key,
 			Value: attr.Value,
 		})
 	}
@@ -135,12 +135,10 @@ func getPluginResourceAttributes(cmd *cobra.Command, plugin Plugin) attribute.Se
 
 func appendPluginResourceAttributesEnvvar(env []string, cmd *cobra.Command, plugin Plugin) []string {
 	if attrs := getPluginResourceAttributes(cmd, plugin); attrs.Len() > 0 {
-		// values in environment variables need to be in baggage format
-		// otel/baggage package can be used after update to v1.22, currently it encodes incorrectly
 		// Construct baggage members for each of the attributes.
 		// Ignore any failures as these aren't significant and
 		// represent an internal issue.
-		var b baggage.Baggage
+		members := make([]baggage.Member, 0, attrs.Len())
 		for iter := attrs.Iter(); iter.Next(); {
 			attr := iter.Attribute()
 			m, err := baggage.NewMemberRaw(string(attr.Key), attr.Value.AsString())
@@ -148,13 +146,7 @@ func appendPluginResourceAttributesEnvvar(env []string, cmd *cobra.Command, plug
 				otel.Handle(err)
 				continue
 			}
-
-			newB, err := b.SetMember(m)
-			if err != nil {
-				otel.Handle(err)
-				continue
-			}
-			b = newB
+			members = append(members, m)
 		}
 
 		// Combine plugin added resource attributes with ones found in the environment
@@ -165,8 +157,10 @@ func appendPluginResourceAttributesEnvvar(env []string, cmd *cobra.Command, plug
 		if v := strings.TrimSpace(os.Getenv(ResourceAttributesEnvvar)); v != "" {
 			attrsSlice = append(attrsSlice, v)
 		}
-		if v := b.String(); v != "" {
-			attrsSlice = append(attrsSlice, v)
+		if b, err := baggage.New(members...); err != nil {
+			otel.Handle(err)
+		} else if b.Len() > 0 {
+			attrsSlice = append(attrsSlice, b.String())
 		}
 
 		if len(attrsSlice) > 0 {

cli-plugins/manager/manager.go

@@ -26,7 +26,7 @@ const (
 
 	// ResourceAttributesEnvvar is the name of the envvar that includes additional
 	// resource attributes for OTEL.
-	ResourceAttributesEnvvar = "OTEL_RESOURCE_ATTRIBUTES"
+	ResourceAttributesEnvvar = command.ResourceAttributesEnvvar
 )
 
 // errPluginNotFound is the error returned when a plugin could not be found.

cli/command/cli.go

@@ -11,6 +11,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
 
@@ -292,6 +293,7 @@ func (cli *DockerCli) Initialize(opts *cliflags.ClientOptions, ops ...CLIOption)
 	if cli.enableGlobalTracer {
 		cli.createGlobalTracerProvider(cli.baseCtx)
 	}
+	filterResourceAttributesEnvvar()
 
 	return nil
 }
@@ -591,3 +593,46 @@ func DefaultContextStoreConfig() store.Config {
 		defaultStoreEndpoints...,
 	)
 }
+
+const (
+	// ResourceAttributesEnvvar is the name of the envvar that includes additional
+	// resource attributes for OTEL.
+	ResourceAttributesEnvvar = "OTEL_RESOURCE_ATTRIBUTES"
+
+	// DockerCliAttributePrefix is the prefix for any docker cli OTEL attributes.
+	DockerCliAttributePrefix = "docker.cli."
+)
+
+func filterResourceAttributesEnvvar() {
+	if v := os.Getenv(ResourceAttributesEnvvar); v != "" {
+		if filtered := filterResourceAttributes(v); filtered != "" {
+			os.Setenv(ResourceAttributesEnvvar, filtered)
+		} else {
+			os.Unsetenv(ResourceAttributesEnvvar)
+		}
+	}
+}
+
+func filterResourceAttributes(s string) string {
+	if trimmed := strings.TrimSpace(s); trimmed == "" {
+		return trimmed
+	}
+
+	pairs := strings.Split(s, ",")
+	elems := make([]string, 0, len(pairs))
+	for _, p := range pairs {
+		k, _, found := strings.Cut(p, "=")
+		if !found {
+			// Do not interact with invalid otel resources.
+			elems = append(elems, p)
+			continue
+		}
+
+		// Skip attributes that have our docker.cli prefix.
+		if strings.HasPrefix(k, DockerCliAttributePrefix) {
+			continue
+		}
+		elems = append(elems, p)
+	}
+	return strings.Join(elems, ",")
+}