move functions supporting images command to libkpod/image

Signed-off-by: Ryan Cole <rcyoalne@gmail.com>

libkpod/image/image.go

@@ -1,11 +1,189 @@
 package image
 
 import (
+	"fmt"
+	"strings"
+	"time"
+
 	is "github.com/containers/image/storage"
 	"github.com/containers/storage"
+	"github.com/kubernetes-incubator/cri-o/libkpod/common"
 	"github.com/pkg/errors"
 )
 
+// FilterParams contains the filter options that may be given when outputting images
+type FilterParams struct {
+	dangling         string
+	label            string
+	beforeImage      time.Time
+	sinceImage       time.Time
+	referencePattern string
+}
+
+// ParseFilter takes a set of images and a filter string as input, and returns the
+func ParseFilter(store storage.Store, filter string) (*FilterParams, error) {
+	images, err := store.Images()
+	if err != nil {
+		return nil, err
+	}
+	params := new(FilterParams)
+	filterStrings := strings.Split(filter, ",")
+	for _, param := range filterStrings {
+		pair := strings.SplitN(param, "=", 2)
+		switch strings.TrimSpace(pair[0]) {
+		case "dangling":
+			if common.IsValidBool(pair[1]) {
+				params.dangling = pair[1]
+			} else {
+				return nil, fmt.Errorf("invalid filter: '%s=[%s]'", pair[0], pair[1])
+			}
+		case "label":
+			params.label = pair[1]
+		case "before":
+			if img, err := findImageInSlice(images, pair[1]); err == nil {
+				params.beforeImage, _ = getCreatedTime(img)
+			} else {
+				return nil, fmt.Errorf("no such id: %s", pair[0])
+			}
+		case "since":
+			if img, err := findImageInSlice(images, pair[1]); err == nil {
+				params.sinceImage, _ = getCreatedTime(img)
+			} else {
+				return nil, fmt.Errorf("no such id: %s``", pair[0])
+			}
+		case "reference":
+			params.referencePattern = pair[1]
+		default:
+			return nil, fmt.Errorf("invalid filter: '%s'", pair[0])
+		}
+	}
+	return params, nil
+}
+
+func matchesFilter(store storage.Store, image storage.Image, name string, params *FilterParams) bool {
+	if params == nil {
+		return true
+	}
+	if params.dangling != "" && !matchesDangling(name, params.dangling) {
+		return false
+	} else if params.label != "" && !matchesLabel(image, store, params.label) {
+		return false
+	} else if !params.beforeImage.IsZero() && !matchesBeforeImage(image, name, params) {
+		return false
+	} else if !params.sinceImage.IsZero() && !matchesSinceImage(image, name, params) {
+		return false
+	} else if params.referencePattern != "" && !MatchesReference(name, params.referencePattern) {
+		return false
+	}
+	return true
+}
+
+func matchesDangling(name string, dangling string) bool {
+	if common.IsFalse(dangling) && name != "<none>" {
+		return true
+	} else if common.IsTrue(dangling) && name == "<none>" {
+		return true
+	}
+	return false
+}
+
+func matchesLabel(image storage.Image, store storage.Store, label string) bool {
+	storeRef, err := is.Transport.ParseStoreReference(store, "@"+image.ID)
+	if err != nil {
+
+	}
+	img, err := storeRef.NewImage(nil)
+	if err != nil {
+		return false
+	}
+	info, err := img.Inspect()
+	if err != nil {
+		return false
+	}
+
+	pair := strings.SplitN(label, "=", 2)
+	for key, value := range info.Labels {
+		if key == pair[0] {
+			if len(pair) == 2 {
+				if value == pair[1] {
+					return true
+				}
+			} else {
+				return false
+			}
+		}
+	}
+	return false
+}
+
+// Returns true if the image was created since the filter image.  Returns
+// false otherwise
+func matchesBeforeImage(image storage.Image, name string, params *FilterParams) bool {
+	if params.beforeImage.IsZero() {
+		return true
+	}
+	createdTime, err := getCreatedTime(image)
+	if err != nil {
+		return false
+	}
+	if createdTime.Before(params.beforeImage) {
+		return true
+	}
+	return false
+}
+
+// Returns true if the image was created since the filter image.  Returns
+// false otherwise
+func matchesSinceImage(image storage.Image, name string, params *FilterParams) bool {
+	if params.sinceImage.IsZero() {
+		return true
+	}
+	createdTime, err := getCreatedTime(image)
+	if err != nil {
+		return false
+	}
+	if createdTime.After(params.beforeImage) {
+		return true
+	}
+	return false
+}
+
+// MatchesID returns true if argID is a full or partial match for id
+func MatchesID(id, argID string) bool {
+	return strings.HasPrefix(id, argID)
+}
+
+// MatchesReference returns true if argName is a full or partial match for name
+// Partial matches will register only if they match the most specific part of the name available
+// For example, take the image docker.io/library/redis:latest
+// redis, library,redis, docker.io/library/redis, redis:latest, etc. will match
+// But redis:alpine, ry/redis, library, and io/library/redis will not
+func MatchesReference(name, argName string) bool {
+	if argName == "" {
+		return true
+	}
+	splitName := strings.Split(name, ":")
+	// If the arg contains a tag, we handle it differently than if it does not
+	if strings.Contains(argName, ":") {
+		splitArg := strings.Split(argName, ":")
+		return strings.HasSuffix(splitName[0], splitArg[0]) && (splitName[1] == splitArg[1])
+	}
+	return strings.HasSuffix(splitName[0], argName)
+}
+
+// FormattedSize returns a human-readable formatted size for the image
+func FormattedSize(size int64) string {
+	suffixes := [5]string{"B", "KB", "MB", "GB", "TB"}
+
+	count := 0
+	formattedSize := float64(size)
+	for formattedSize >= 1024 && count < 4 {
+		formattedSize /= 1024
+		count++
+	}
+	return fmt.Sprintf("%.4g %s", formattedSize, suffixes[count])
+}
+
 // FindImage searches for an image with a matching the given name or ID in the given store
 func FindImage(store storage.Store, image string) (*storage.Image, error) {
 	var img *storage.Image
@@ -26,6 +204,20 @@ func FindImage(store storage.Store, image string) (*storage.Image, error) {
 	return img, nil
 }
 
+func findImageInSlice(images []storage.Image, ref string) (storage.Image, error) {
+	for _, image := range images {
+		if MatchesID(image.ID, ref) {
+			return image, nil
+		}
+		for _, name := range image.Names {
+			if MatchesReference(name, ref) {
+				return image, nil
+			}
+		}
+	}
+	return storage.Image{}, errors.New("could not find image")
+}
+
 // Size returns the size of the image in the given store
 func Size(store storage.Store, img storage.Image) (int64, error) {
 	is.Transport.SetStore(store)
@@ -55,3 +247,40 @@ func GetTopLayerID(img storage.Image) (string, error) {
 	// Return the first layer associated with the given digest
 	return metadata.Layers[digest][0], nil
 }
+
+func getCreatedTime(image storage.Image) (time.Time, error) {
+	metadata, err := ParseMetadata(image)
+	if err != nil {
+		return time.Time{}, err
+	}
+	return metadata.CreatedTime, nil
+}
+
+// GetImagesMatchingFilter returns a slice of all images in the store that match the provided FilterParams.
+// Images with more than one name matching the filter will be in the slice once for each name
+func GetImagesMatchingFilter(store storage.Store, filter *FilterParams, argName string) ([]storage.Image, error) {
+	images, err := store.Images()
+	filteredImages := []storage.Image{}
+	if err != nil {
+		return nil, err
+	}
+	if filter == nil {
+		return images, nil
+	}
+	for _, image := range images {
+		names := []string{}
+		if len(image.Names) > 0 {
+			names = image.Names
+		} else {
+			names = append(names, "<none>")
+		}
+		for _, name := range names {
+			if matchesFilter(store, image, name, filter) || MatchesReference(name, argName) {
+				newImage := image
+				newImage.Names = []string{name}
+				filteredImages = append(filteredImages, newImage)
+			}
+		}
+	}
+	return filteredImages, nil
+}