cli/command: un-export ResourceAttributesEnvvar, DockerCliAttributePrefix

These utility functions were added in 8890a1c929,
and are all related to OTEL. The ResourceAttributesEnvvar const defines
the "OTEL_RESOURCE_ATTRIBUTES" environment-variable to use, which is part
of the [OpenTelemetry specification], so should be considered a well-known
env-var, and not up to us to define a const for. These code-changes were not
yet included in a release, so we don't have to deprecate.

This patch:

- Moves the utility functions to the telemetry files, so that all code related
  to OpenTelemetry is together.
- Un-exports the ResourceAttributesEnvvar to reduce our public API.
- Un-exports the DockerCliAttributePrefix to reduce depdency on cli/command
  in CLI-plugins, but adds a TODO to move telemetry-related code to a common
  (internal) package.
- Deprecates the cli-plugins/manager.ResourceAttributesEnvvar const. This
  const has no known consumers, so we could skip deprecation, but just in
  case some codebase uses this.

[OpenTelemetry specification]: https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#general-sdk-configuration

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli-plugins/manager/cobra.go

@@ -107,9 +107,17 @@ func AddPluginCommandStubs(dockerCli command.Cli, rootCmd *cobra.Command) (err e
 }
 
 const (
-	dockerCliAttributePrefix = command.DockerCliAttributePrefix
+	// resourceAttributesEnvVar is the name of the envvar that includes additional
+	// resource attributes for OTEL as defined in the [OpenTelemetry specification].
+	//
+	// [OpenTelemetry specification]: https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#general-sdk-configuration
+	resourceAttributesEnvVar = "OTEL_RESOURCE_ATTRIBUTES"
 
-	cobraCommandPath = attribute.Key("cobra.command_path")
+	// dockerCLIAttributePrefix is the prefix for any docker cli OTEL attributes.
+	//
+	// It is a copy of the const defined in [command.dockerCLIAttributePrefix].
+	dockerCLIAttributePrefix = "docker.cli."
+	cobraCommandPath         = attribute.Key("cobra.command_path")
 )
 
 func getPluginResourceAttributes(cmd *cobra.Command, plugin Plugin) attribute.Set {
@@ -126,7 +134,7 @@ 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,
 		})
 	}
@@ -154,7 +162,7 @@ func appendPluginResourceAttributesEnvvar(env []string, cmd *cobra.Command, plug
 		// conflict. We do not parse the environment variable because we do not want
 		// to handle errors in user configuration.
 		attrsSlice := make([]string, 0, 2)
-		if v := strings.TrimSpace(os.Getenv(ResourceAttributesEnvvar)); v != "" {
+		if v := strings.TrimSpace(os.Getenv(resourceAttributesEnvVar)); v != "" {
 			attrsSlice = append(attrsSlice, v)
 		}
 		if b, err := baggage.New(members...); err != nil {
@@ -164,7 +172,7 @@ func appendPluginResourceAttributesEnvvar(env []string, cmd *cobra.Command, plug
 		}
 
 		if len(attrsSlice) > 0 {
-			env = append(env, ResourceAttributesEnvvar+"="+strings.Join(attrsSlice, ","))
+			env = append(env, resourceAttributesEnvVar+"="+strings.Join(attrsSlice, ","))
 		}
 	}
 	return env

cli-plugins/manager/manager.go

@@ -26,7 +26,9 @@ const (
 
 	// ResourceAttributesEnvvar is the name of the envvar that includes additional
 	// resource attributes for OTEL.
-	ResourceAttributesEnvvar = command.ResourceAttributesEnvvar
+	//
+	// Deprecated: The "OTEL_RESOURCE_ATTRIBUTES" env-var is part of the OpenTelemetry specification; users should define their own const for this. This const will be removed in the next release.
+	ResourceAttributesEnvvar = "OTEL_RESOURCE_ATTRIBUTES"
 )
 
 // errPluginNotFound is the error returned when a plugin could not be found.

cli/command/cli.go

@@ -11,7 +11,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"strconv"
-	"strings"
 	"sync"
 	"time"
 
@@ -593,46 +592,3 @@ 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, ",")
-}

cli/command/telemetry.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"time"
 
@@ -216,3 +217,49 @@ func (r *cliReader) ForceFlush(ctx context.Context) error {
 func deltaTemporality(_ sdkmetric.InstrumentKind) metricdata.Temporality {
 	return metricdata.DeltaTemporality
 }
+
+// resourceAttributesEnvVar is the name of the envvar that includes additional
+// resource attributes for OTEL as defined in the [OpenTelemetry specification].
+//
+// [OpenTelemetry specification]: https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#general-sdk-configuration
+const resourceAttributesEnvVar = "OTEL_RESOURCE_ATTRIBUTES"
+
+func filterResourceAttributesEnvvar() {
+	if v := os.Getenv(resourceAttributesEnvVar); v != "" {
+		if filtered := filterResourceAttributes(v); filtered != "" {
+			_ = os.Setenv(resourceAttributesEnvVar, filtered)
+		} else {
+			_ = os.Unsetenv(resourceAttributesEnvVar)
+		}
+	}
+}
+
+// dockerCLIAttributePrefix is the prefix for any docker cli OTEL attributes.
+// When updating, make sure to also update the copy in cli-plugins/manager.
+//
+// TODO(thaJeztah): move telemetry-related code to an (internal) package to reduce dependency on cli/command in cli-plugins, which has too many imports.
+const dockerCLIAttributePrefix = "docker.cli."
+
+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, ",")
+}