[FEAT] Add container filesystem size capability

capabilities/filesystem/filesystem.go

@@ -0,0 +1,55 @@
+package filesystem
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/puppetlabs/lumogon/capabilities/payloadfilter"
+	"github.com/puppetlabs/lumogon/capabilities/registry"
+	"github.com/puppetlabs/lumogon/dockeradapter"
+	"github.com/puppetlabs/lumogon/logging"
+	"github.com/puppetlabs/lumogon/types"
+)
+
+var filesystemDescription = `The filesystem capability returns sizes of filesystem in a container as a map["layer"]"size"`
+
+// The filesystemCapability capability output from the container runtime inspect
+var filesystemCapability = dockeradapter.DockerAPICapability{
+	Capability: types.Capability{
+		Schema:      "http://puppet.com/lumogon/capability/diff/draft-01/schema#1",
+		Title:       "Filesystem",
+		Name:        "filesystem",
+		Description: filesystemDescription,
+		Type:        "dockerapi",
+		Payload:     nil,
+		SupportedOS: map[string]int{"all": 1},
+	},
+	Harvest: func(capability *dockeradapter.DockerAPICapability, client dockeradapter.Harvester, id string, target types.TargetContainer) {
+		logging.Stderr("[Filesystem] Harvesting filesystem sizes from %s [%s]", target.Name, target.ID)
+		capability.HarvestID = id
+		logging.Stderr("[Filesystem] Harvesting filesystem capability, harvestid: %s", capability.HarvestID)
+
+		ctx := context.Background()
+		output := make(map[string]interface{})
+
+		containerData, err := client.ContainerFilesystem(ctx, target.ID)
+		if err != nil {
+			errorMsg := fmt.Sprintf("[Filesystem] Error getting filesystem data from targetContainer: %s, error: %s", target.Name, err)
+			logging.Stderr(errorMsg)
+			capability.PayloadError(errorMsg)
+			return
+		}
+
+		output["sizerw"] = containerData.SizeRw
+		output["sizerootfs"] = containerData.SizeRootFs
+		filtered, _ := payloadfilter.Filter(output)
+		logging.Stderr("[Filesystem]   Output: %v", output)
+		logging.Stderr("[Filesystem]   Filtered: %v", filtered)
+		capability.Payload = filtered
+	},
+}
+
+func init() {
+	logging.Stderr("[Filesystem] Initialising capability: %s", filesystemCapability.Title)
+	registry.Registry.Add(filesystemCapability)
+}

capabilities/filesystem/init.go

@@ -0,0 +1,7 @@
+package filesystem
+
+// Init exists to allow host init() functions to run when
+// invoked from the capabilities Init function, which is
+// itself invoked by the Lumogon command handler.
+func Init() {
+}

capabilities/init.go

@@ -1,6 +1,7 @@
 package capabilities
 
 import (
+	"github.com/puppetlabs/lumogon/capabilities/filesystem"
 	"github.com/puppetlabs/lumogon/capabilities/host"
 	"github.com/puppetlabs/lumogon/capabilities/label"
 	"github.com/puppetlabs/lumogon/capabilities/ospackages"
@@ -9,7 +10,9 @@ import (
 // Init exists to allow capabilities init() functions to run when
 // invoked from the Lumogon command handler.
 func Init() {
+
 	host.Init()
 	label.Init()
 	ospackages.Init()
+	filesystem.Init()
 }

dockeradapter/dockeradapter.go

@@ -5,10 +5,13 @@ import (
 	"fmt"
 	"io"
 
+	"github.com/davecgh/go-spew/spew"
 	dockertypes "github.com/docker/docker/api/types"
 	dockercontainer "github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/client"
 	"github.com/puppetlabs/lumogon/logging"
+	"github.com/puppetlabs/lumogon/types"
 	"github.com/puppetlabs/lumogon/utils"
 )
 
@@ -25,12 +28,14 @@ type Client interface {
 	Lister
 	HostInspector
 	CopyFrom
+	Filesystem
 }
 
 // Harvester interface exposes methods used by Capabilties Harvest functions
 type Harvester interface {
 	Inspector
 	Executor
+	Filesystem
 }
 
 // ImagePuller interface exposes methods required to pull an image
@@ -98,6 +103,11 @@ type CopyFrom interface {
 	CopyFromContainer(ctx context.Context, container, srcPath string, followSymlink bool) (io.ReadCloser, dockertypes.ContainerPathStat, error)
 }
 
+// Filesystem type contains information on the container filesystem
+type Filesystem interface {
+	ContainerFilesystem(ctx context.Context, containerID string) (types.Filesystem, error)
+}
+
 // containerLogOptions type contains values used to control logs returned
 // from a container
 type containerLogOptions struct {
@@ -269,6 +279,36 @@ func (c *concreteDockerClient) ContainerList(ctx context.Context) ([]string, err
 	return result, nil
 }
 
+func (c *concreteDockerClient) ContainerFilesystem(ctx context.Context, containerID string) (types.Filesystem, error) {
+	result := types.Filesystem{}
+
+	filter := filters.NewArgs()
+	filter.Add("id", containerID)
+
+	options := dockertypes.ContainerListOptions{
+		All:     true,
+		Filters: filter,
+	}
+
+	containers, err := c.Client.ContainerList(ctx, options)
+	if err != nil {
+		return result, err
+	}
+
+	logging.Stderr("[Filesystem] %s", spew.Sprintf("%#+v", containers))
+
+	if len(containers) != 1 {
+		return result, fmt.Errorf("container lookup should return 1 container but returned %d", len(containers))
+	}
+
+	for _, container := range containers {
+		result.SizeRw = container.SizeRw
+		result.SizeRootFs = container.SizeRootFs
+	}
+
+	return result, nil
+}
+
 // stripDockerLogsHeader (DEPRECATED) strips the Docker logs header and aims to return a string
 func stripDockerLogsHeader(rawlogs string) string {
 	headerLength := 8

test/mocks/dockerclient.go

@@ -7,6 +7,7 @@ import (
 
 	dockertypes "github.com/docker/docker/api/types"
 	dockercontainer "github.com/docker/docker/api/types/container"
+	"github.com/puppetlabs/lumogon/types"
 	"github.com/puppetlabs/lumogon/utils"
 )
 
@@ -30,6 +31,7 @@ type MockDockerClient struct {
 	ContainerExecInspectFn func(ctx context.Context, execID string) (dockertypes.ContainerExecInspect, error)
 	ImageInspectFn         func(ctx context.Context, imageName string) (dockertypes.ImageInspect, error)
 	CopyFromContainerFn    func(ctx context.Context, container, srcPath string, followSymlink bool) (io.ReadCloser, dockertypes.ContainerPathStat, error)
+	ContainerFilesystemFn  func(ctx context.Context, containerID string) (types.Filesystem, error)
 }
 
 // ImagePull is a mock implementation of dockeradapter.ImagePull
@@ -196,3 +198,12 @@ func (c MockDockerClient) CopyFromContainer(ctx context.Context, container, srcP
 	}
 	panic(fmt.Sprintf("No function defined for: %s", utils.CurrentFunctionName()))
 }
+
+// ContainerFilesystem is a mock implementation of dockeradapter.ContainerFilesystem
+func (c MockDockerClient) ContainerFilesystem(ctx context.Context, containerID string) (types.Filesystem, error) {
+	if c.ContainerFilesystemFn != nil {
+		fmt.Println("[MockDockerClient] In ", utils.CurrentFunctionName())
+		return c.ContainerFilesystemFn(ctx, containerID)
+	}
+	panic(fmt.Sprintf("No function defined for: %s", utils.CurrentFunctionName()))
+}

types/filesystem.go

@@ -0,0 +1,7 @@
+package types
+
+// Filesystem captures size information for a container's filesystem and root filesystem
+type Filesystem struct {
+	SizeRw     int64 `json:"sizerw"`
+	SizeRootFs int64 `json:"sizerootfs"`
+}