From a022fa71b7459640ce520ef88d023fdb893998b8 Mon Sep 17 00:00:00 2001
From: Jordan Liggitt <liggitt@google.com>
Date: Tue, 9 Apr 2019 21:50:26 +0000
Subject: [PATCH] Split docker context initialization

---
 container/docker/plugin.go | 39 ++++++++++++++++++++++++++++++++++
 manager/manager.go         | 43 +-------------------------------------
 2 files changed, 40 insertions(+), 42 deletions(-)

diff --git a/container/docker/plugin.go b/container/docker/plugin.go
index 63938db8..c4ca43a4 100644
--- a/container/docker/plugin.go
+++ b/container/docker/plugin.go
@@ -15,12 +15,18 @@
 package docker
 
 import (
+	"time"
+
 	"github.com/google/cadvisor/container"
 	"github.com/google/cadvisor/fs"
 	info "github.com/google/cadvisor/info/v1"
 	"github.com/google/cadvisor/watcher"
+	"golang.org/x/net/context"
+	"k8s.io/klog"
 )
 
+const dockerClientTimeout = 10 * time.Second
+
 // NewPlugin returns an implementation of container.Plugin suitable for passing to container.RegisterPlugin()
 func NewPlugin() container.Plugin {
 	return &plugin{}
@@ -29,6 +35,14 @@ func NewPlugin() container.Plugin {
 type plugin struct{}
 
 func (p *plugin) InitializeFSContext(context *fs.Context) error {
+	SetTimeout(dockerClientTimeout)
+	// Try to connect to docker indefinitely on startup.
+	dockerStatus := retryDockerStatus()
+	context.Docker = fs.DockerContext{
+		Root:         RootDir(),
+		Driver:       dockerStatus.Driver,
+		DriverStatus: dockerStatus.DriverStatus,
+	}
 	return nil
 }
 
@@ -36,3 +50,28 @@ func (p *plugin) Register(factory info.MachineInfoFactory, fsInfo fs.FsInfo, inc
 	err := Register(factory, fsInfo, includedMetrics)
 	return nil, err
 }
+
+func retryDockerStatus() info.DockerStatus {
+	startupTimeout := dockerClientTimeout
+	maxTimeout := 4 * startupTimeout
+	for {
+		ctx, _ := context.WithTimeout(context.Background(), startupTimeout)
+		dockerStatus, err := StatusWithContext(ctx)
+		if err == nil {
+			return dockerStatus
+		}
+
+		switch err {
+		case context.DeadlineExceeded:
+			klog.Warningf("Timeout trying to communicate with docker during initialization, will retry")
+		default:
+			klog.V(5).Infof("Docker not connected: %v", err)
+			return info.DockerStatus{}
+		}
+
+		startupTimeout = 2 * startupTimeout
+		if startupTimeout > maxTimeout {
+			startupTimeout = maxTimeout
+		}
+	}
+}
diff --git a/manager/manager.go b/manager/manager.go
index e9225aa1..ab1770b8 100644
--- a/manager/manager.go
+++ b/manager/manager.go
@@ -43,7 +43,6 @@ import (
 	"github.com/google/cadvisor/watcher"
 
 	"github.com/opencontainers/runc/libcontainer/cgroups"
-	"golang.org/x/net/context"
 	"k8s.io/klog"
 	"k8s.io/utils/clock"
 )
@@ -55,8 +54,6 @@ var eventStorageAgeLimit = flag.String("event_storage_age_limit", "default=24h",
 var eventStorageEventLimit = flag.String("event_storage_event_limit", "default=100000", "Max number of events to store (per type). Value is a comma separated list of key values, where the keys are event types (e.g.: creation, oom) or \"default\" and the value is an integer. Default is applied to all non-specified event types")
 var applicationMetricsCountLimit = flag.Int("application_metrics_count_limit", 100, "Max number of application metrics to store (per container)")
 
-const dockerClientTimeout = 10 * time.Second
-
 // The Manager interface defines operations for starting a manager and getting
 // container and machine information.
 type Manager interface {
@@ -148,20 +145,7 @@ func New(memoryCache *memory.InMemoryCache, sysfs sysfs.SysFs, maxHousekeepingIn
 	}
 	klog.V(2).Infof("cAdvisor running in container: %q", selfContainer)
 
-	var (
-		dockerStatus info.DockerStatus
-	)
-	docker.SetTimeout(dockerClientTimeout)
-	// Try to connect to docker indefinitely on startup.
-	dockerStatus = retryDockerStatus()
-
-	context := fs.Context{
-		Docker: fs.DockerContext{
-			Root:         docker.RootDir(),
-			Driver:       dockerStatus.Driver,
-			DriverStatus: dockerStatus.DriverStatus,
-		},
-	}
+	context := fs.Context{}
 
 	if err := container.InitializeFSContext(&context); err != nil {
 		return nil, err
@@ -218,31 +202,6 @@ func New(memoryCache *memory.InMemoryCache, sysfs sysfs.SysFs, maxHousekeepingIn
 	return newManager, nil
 }
 
-func retryDockerStatus() info.DockerStatus {
-	startupTimeout := dockerClientTimeout
-	maxTimeout := 4 * startupTimeout
-	for {
-		ctx, _ := context.WithTimeout(context.Background(), startupTimeout)
-		dockerStatus, err := docker.StatusWithContext(ctx)
-		if err == nil {
-			return dockerStatus
-		}
-
-		switch err {
-		case context.DeadlineExceeded:
-			klog.Warningf("Timeout trying to communicate with docker during initialization, will retry")
-		default:
-			klog.V(5).Infof("Docker not connected: %v", err)
-			return info.DockerStatus{}
-		}
-
-		startupTimeout = 2 * startupTimeout
-		if startupTimeout > maxTimeout {
-			startupTimeout = maxTimeout
-		}
-	}
-}
-
 // A namespaced container name.
 type namespacedContainerName struct {
 	// The namespace of the container. Can be empty for the root namespace.