From 0d907e015b784a4edeb17c0580bf1e408c966de7 Mon Sep 17 00:00:00 2001
From: Arnav Sankaran <arnavs@uber.com>
Date: Wed, 10 Jul 2019 14:00:20 -0700
Subject: [PATCH] Add ImageFSInfo, ContainerStats, and ListContainerStats impl
 for linux to dockershim

---
 pkg/kubelet/dockershim/docker_image_linux.go | 50 +++++++++++-
 pkg/kubelet/dockershim/docker_stats_linux.go | 84 +++++++++++++++++++-
 2 files changed, 128 insertions(+), 6 deletions(-)

diff --git a/pkg/kubelet/dockershim/docker_image_linux.go b/pkg/kubelet/dockershim/docker_image_linux.go
index e68d83b19ab..0762d26334c 100644
--- a/pkg/kubelet/dockershim/docker_image_linux.go
+++ b/pkg/kubelet/dockershim/docker_image_linux.go
@@ -20,12 +20,58 @@ package dockershim
 
 import (
 	"context"
-	"fmt"
+	"path/filepath"
+	"os"
+	"time"
+
+	"k8s.io/klog"
 
 	runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1alpha2"
 )
 
 // ImageFsInfo returns information of the filesystem that is used to store images.
 func (ds *dockerService) ImageFsInfo(_ context.Context, r *runtimeapi.ImageFsInfoRequest) (*runtimeapi.ImageFsInfoResponse, error) {
-	return nil, fmt.Errorf("not implemented")
+	info, err := ds.client.Info()
+	if err != nil {
+		klog.Errorf("Failed to get docker info: %v", err)
+		return nil, err
+	}
+
+	bytes, inodes, err := dirSize(filepath.Join(info.DockerRootDir, "image"))
+	if err != nil {
+		return nil, err
+	}
+
+	return &runtimeapi.ImageFsInfoResponse{
+		ImageFilesystems: []*runtimeapi.FilesystemUsage{
+			&runtimeapi.FilesystemUsage{
+				Timestamp: time.Now().Unix(),
+				FsId: &runtimeapi.FilesystemIdentifier{
+					Mountpoint: info.DockerRootDir,
+				},
+				UsedBytes: &runtimeapi.UInt64Value{
+					Value: uint64(bytes),
+				},
+				InodesUsed: &runtimeapi.UInt64Value{
+					Value: uint64(inodes),
+				},
+			},
+		},
+	}, nil
+}
+
+func dirSize(path string) (int64, int64, error) {
+	bytes := int64(0)
+	inodes := int64(0)
+	err := filepath.Walk(path, func(dir string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		inodes += 1
+		if !info.IsDir() {
+			bytes += info.Size()
+		}
+		return nil
+	})
+	return bytes, inodes, err
 }
diff --git a/pkg/kubelet/dockershim/docker_stats_linux.go b/pkg/kubelet/dockershim/docker_stats_linux.go
index b78ff9c3c95..d0f3cd463c0 100644
--- a/pkg/kubelet/dockershim/docker_stats_linux.go
+++ b/pkg/kubelet/dockershim/docker_stats_linux.go
@@ -20,17 +20,93 @@ package dockershim
 
 import (
 	"context"
-	"fmt"
+	"time"
 
 	runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1alpha2"
 )
 
 // ContainerStats returns stats for a container stats request based on container id.
 func (ds *dockerService) ContainerStats(_ context.Context, r *runtimeapi.ContainerStatsRequest) (*runtimeapi.ContainerStatsResponse, error) {
-	return nil, fmt.Errorf("not implemented")
+	stats, err := ds.getContainerStats(r.ContainerId)
+	if err != nil {
+		return nil, err
+	}
+	return &runtimeapi.ContainerStatsResponse{Stats: stats}, nil
 }
 
 // ListContainerStats returns stats for a list container stats request based on a filter.
-func (ds *dockerService) ListContainerStats(_ context.Context, r *runtimeapi.ListContainerStatsRequest) (*runtimeapi.ListContainerStatsResponse, error) {
-	return nil, fmt.Errorf("not implemented")
+func (ds *dockerService) ListContainerStats(ctx context.Context, r *runtimeapi.ListContainerStatsRequest) (*runtimeapi.ListContainerStatsResponse, error) {
+	containerStatsFilter := r.GetFilter()
+	filter := &runtimeapi.ContainerFilter{}
+
+	if containerStatsFilter != nil {
+		filter.Id = containerStatsFilter.Id
+		filter.PodSandboxId = containerStatsFilter.PodSandboxId
+		filter.LabelSelector = containerStatsFilter.LabelSelector
+	}
+
+	listResp, err := ds.ListContainers(ctx, &runtimeapi.ListContainersRequest{Filter: filter})
+	if err != nil {
+		return nil, err
+	}
+
+	var stats []*runtimeapi.ContainerStats
+	for _, container := range listResp.Containers {
+		containerStats, err := ds.getContainerStats(container.Id)
+		if err != nil {
+			return nil, err
+		}
+
+		stats = append(stats, containerStats)
+	}
+
+	return &runtimeapi.ListContainerStatsResponse{Stats: stats}, nil
+}
+
+func (ds *dockerService) getContainerStats(containerID string) (*runtimeapi.ContainerStats, error) {
+	info, err := ds.client.Info()
+	if err != nil {
+		return nil, err
+	}
+
+	statsJSON, err := ds.client.GetContainerStats(containerID)
+	if err != nil {
+		return nil, err
+	}
+
+	containerJSON, err := ds.client.InspectContainerWithSize(containerID)
+	if err != nil {
+		return nil, err
+	}
+
+	statusResp, err := ds.ContainerStatus(context.Background(), &runtimeapi.ContainerStatusRequest{ContainerId: containerID})
+	if err != nil {
+		return nil, err
+	}
+	status := statusResp.GetStatus()
+
+	dockerStats := statsJSON.Stats
+	timestamp := time.Now().UnixNano()
+	containerStats := &runtimeapi.ContainerStats{
+		Attributes: &runtimeapi.ContainerAttributes{
+			Id:          containerID,
+			Metadata:    status.Metadata,
+			Labels:      status.Labels,
+			Annotations: status.Annotations,
+		},
+		Cpu: &runtimeapi.CpuUsage{
+			Timestamp: timestamp,
+			UsageCoreNanoSeconds: &runtimeapi.UInt64Value{Value: dockerStats.CPUStats.CPUUsage.TotalUsage},
+		},
+		Memory: &runtimeapi.MemoryUsage{
+			Timestamp:       timestamp,
+			WorkingSetBytes: &runtimeapi.UInt64Value{Value: dockerStats.MemoryStats.PrivateWorkingSet},
+		},
+		WritableLayer: &runtimeapi.FilesystemUsage{
+			Timestamp: timestamp,
+			FsId:      &runtimeapi.FilesystemIdentifier{Mountpoint: info.DockerRootDir},
+			UsedBytes: &runtimeapi.UInt64Value{Value: uint64(*containerJSON.SizeRw)},
+		},
+	}
+	return containerStats, nil
 }