Refactor: Move container metric metadata helpers into their own package.

PiperOrigin-RevId: 557298185

runsc/cmd/BUILD

@@ -78,6 +78,7 @@ go_library(
         "//runsc/fsgofer",
         "//runsc/fsgofer/filter",
         "//runsc/metricserver",
+        "//runsc/metricserver/containermetrics",
         "//runsc/mitigate",
         "//runsc/profile",
         "//runsc/specutils",

runsc/cmd/metric_export.go

@@ -26,7 +26,7 @@ import (
 	"gvisor.dev/gvisor/runsc/config"
 	"gvisor.dev/gvisor/runsc/container"
 	"gvisor.dev/gvisor/runsc/flag"
-	"gvisor.dev/gvisor/runsc/metricserver"
+	"gvisor.dev/gvisor/runsc/metricserver/containermetrics"
 )
 
 // MetricExport implements subcommands.Command for the "metric-export" command.
@@ -72,7 +72,7 @@ func (m *MetricExport) Execute(ctx context.Context, f *flag.FlagSet, args ...any
 		util.Fatalf("loading container: %v", err)
 	}
 
-	prometheusLabels, err := metricserver.SandboxPrometheusLabels(cont)
+	prometheusLabels, err := containermetrics.SandboxPrometheusLabels(cont)
 	if err != nil {
 		util.Fatalf("Cannot compute Prometheus labels of sandbox: %v", err)
 	}

runsc/metricserver/BUILD

@@ -25,6 +25,7 @@ go_library(
         "//pkg/sync",
         "//runsc/config",
         "//runsc/container",
+        "//runsc/metricserver/containermetrics",
         "//runsc/sandbox",
         "@org_golang_google_api//option:go_default_library",
         "@org_golang_google_grpc//:go_default_library",

runsc/metricserver/containermetrics/BUILD

@@ -0,0 +1,18 @@
+load("//tools:defs.bzl", "go_library")
+
+package(
+    default_applicable_licenses = ["//:license"],
+    licenses = ["notice"],
+)
+
+go_library(
+    name = "containermetrics",
+    srcs = ["containermetrics.go"],
+    visibility = [
+        "//:sandbox",
+    ],
+    deps = [
+        "//pkg/prometheus",
+        "//runsc/container",
+    ],
+)

runsc/metricserver/containermetrics/containermetrics.go

@@ -0,0 +1,87 @@
+// Copyright 2023 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package containermetrics returns metrics and labels interesting to export
+// about a container or sandbox.
+package containermetrics
+
+import (
+	"crypto/sha256"
+	"encoding/binary"
+	"io"
+	"strconv"
+
+	"gvisor.dev/gvisor/pkg/prometheus"
+	"gvisor.dev/gvisor/runsc/container"
+)
+
+// SandboxPrometheusLabels returns a set of Prometheus labels that identifies the sandbox running
+// the given root container.
+func SandboxPrometheusLabels(rootContainer *container.Container) (map[string]string, error) {
+	s := rootContainer.Sandbox
+	labels := make(map[string]string, 4)
+	labels[prometheus.SandboxIDLabel] = s.ID
+
+	// Compute iteration ID label in a stable manner.
+	// This uses sha256(ID + ":" + creation time).
+	h := sha256.New()
+	if _, err := io.WriteString(h, s.ID); err != nil {
+		return nil, err
+	}
+	if _, err := io.WriteString(h, ":"); err != nil {
+		return nil, err
+	}
+	if _, err := io.WriteString(h, rootContainer.CreatedAt.UTC().String()); err != nil {
+		return nil, err
+	}
+	labels[prometheus.IterationIDLabel] = strconv.FormatUint(binary.BigEndian.Uint64(h.Sum(nil)[:8]), 36)
+
+	if s.PodName != "" {
+		labels[prometheus.PodNameLabel] = s.PodName
+	}
+	if s.Namespace != "" {
+		labels[prometheus.NamespaceLabel] = s.Namespace
+	}
+	return labels, nil
+}
+
+// ComputeSpecMetadata returns the labels for the `spec_metadata` metric.
+// It merges data from the Specs of multiple containers running within the
+// same sandbox.
+// This function must support being called with `allContainers` being nil.
+// It must return the same set of label keys regardless of how many containers
+// are in `allContainers`.
+func ComputeSpecMetadata(allContainers []*container.Container) map[string]string {
+	const (
+		unknownOCIVersion      = "UNKNOWN"
+		inconsistentOCIVersion = "INCONSISTENT"
+	)
+
+	hasUID0Container := false
+	ociVersion := unknownOCIVersion
+	for _, cont := range allContainers {
+		if cont.RunsAsUID0() {
+			hasUID0Container = true
+		}
+		if ociVersion == unknownOCIVersion {
+			ociVersion = cont.Spec.Version
+		} else if ociVersion != cont.Spec.Version {
+			ociVersion = inconsistentOCIVersion
+		}
+	}
+	return map[string]string{
+		"hasuid0":    strconv.FormatBool(hasUID0Container),
+		"ociversion": ociVersion,
+	}
+}

runsc/metricserver/metricserver.go

@@ -43,6 +43,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/runsc/config"
 	"gvisor.dev/gvisor/runsc/container"
+	"gvisor.dev/gvisor/runsc/metricserver/containermetrics"
 	"gvisor.dev/gvisor/runsc/sandbox"
 )
 
@@ -141,7 +142,7 @@ func (s *servedSandbox) load() (*sandbox.Sandbox, *prometheus.Verifier, error) {
 		}
 		// Update label data as read from the state file.
 		// Do not store empty labels.
-		authoritativeLabels, err := SandboxPrometheusLabels(rootContainer)
+		authoritativeLabels, err := containermetrics.SandboxPrometheusLabels(rootContainer)
 		if err != nil {
 			return nil, nil, fmt.Errorf("cannot compute Prometheus labels of sandbox: %v", err)
 		}
@@ -178,7 +179,7 @@ func (s *servedSandbox) load() (*sandbox.Sandbox, *prometheus.Verifier, error) {
 		}
 
 		// Compute spec metadata.
-		s.specMetadataLabels = ComputeSpecMetadata(allContainers)
+		s.specMetadataLabels = containermetrics.ComputeSpecMetadata(allContainers)
 
 		s.sandbox = rootContainer.Sandbox
 		s.createdAt = rootContainer.CreatedAt

runsc/metricserver/metricserver_metrics.go

@@ -15,13 +15,7 @@
 package metricserver
 
 import (
-	"crypto/sha256"
-	"encoding/binary"
-	"io"
-	"strconv"
-
 	"gvisor.dev/gvisor/pkg/prometheus"
-	"gvisor.dev/gvisor/runsc/container"
 )
 
 // Metrics generated by the metrics server itself.
@@ -87,63 +81,3 @@ var Metrics = []*prometheus.Metric{
 	&NumTotalSandboxesMetric,
 	&prometheus.ProcessStartTimeSeconds,
 }
-
-// SandboxPrometheusLabels returns a set of Prometheus labels that identifies the sandbox running
-// the given root container.
-func SandboxPrometheusLabels(rootContainer *container.Container) (map[string]string, error) {
-	s := rootContainer.Sandbox
-	labels := make(map[string]string, 4)
-	labels[prometheus.SandboxIDLabel] = s.ID
-
-	// Compute iteration ID label in a stable manner.
-	// This uses sha256(ID + ":" + creation time).
-	h := sha256.New()
-	if _, err := io.WriteString(h, s.ID); err != nil {
-		return nil, err
-	}
-	if _, err := io.WriteString(h, ":"); err != nil {
-		return nil, err
-	}
-	if _, err := io.WriteString(h, rootContainer.CreatedAt.UTC().String()); err != nil {
-		return nil, err
-	}
-	labels[prometheus.IterationIDLabel] = strconv.FormatUint(binary.BigEndian.Uint64(h.Sum(nil)[:8]), 36)
-
-	if s.PodName != "" {
-		labels[prometheus.PodNameLabel] = s.PodName
-	}
-	if s.Namespace != "" {
-		labels[prometheus.NamespaceLabel] = s.Namespace
-	}
-	return labels, nil
-}
-
-// ComputeSpecMetadata returns the labels for the `spec_metadata` metric.
-// It merges data from the Specs of multiple containers running within the
-// same sandbox.
-// This function must support being called with `allContainers` being nil.
-// It must return the same set of label keys regardless of how many containers
-// are in `allContainers`.
-func ComputeSpecMetadata(allContainers []*container.Container) map[string]string {
-	const (
-		unknownOCIVersion      = "UNKNOWN"
-		inconsistentOCIVersion = "INCONSISTENT"
-	)
-
-	hasUID0Container := false
-	ociVersion := unknownOCIVersion
-	for _, cont := range allContainers {
-		if cont.RunsAsUID0() {
-			hasUID0Container = true
-		}
-		if ociVersion == unknownOCIVersion {
-			ociVersion = cont.Spec.Version
-		} else if ociVersion != cont.Spec.Version {
-			ociVersion = inconsistentOCIVersion
-		}
-	}
-	return map[string]string{
-		"hasuid0":    strconv.FormatBool(hasUID0Container),
-		"ociversion": ociVersion,
-	}
-}