Merge pull request #209 from nkubala/metadata_diff

Add metadata diffing

Author: nkubala

cmd/analyze.go

@@ -87,7 +87,7 @@ func analyzeImage(imageName string, analyzerArgs []string) error {
 		return fmt.Errorf("Error performing image analysis: %s", err)
 	}
 
-	output.PrintToStdErr("Retrieving analyses")
+	output.PrintToStdErr("Retrieving analyses\n")
 	outputResults(analyses)
 
 	if save {

cmd/diff.go

@@ -113,7 +113,7 @@ func diffImages(image1Arg, image2Arg string, diffArgs []string) error {
 		defer pkgutil.CleanupImage(*imageMap[image2Arg])
 	}
 
-	output.PrintToStdErr("Computing diffs")
+	output.PrintToStdErr("Computing diffs\n")
 	req := differs.DiffRequest{
 		Image1:    *imageMap[image1Arg],
 		Image2:    *imageMap[image2Arg],
@@ -125,7 +125,7 @@ func diffImages(image1Arg, image2Arg string, diffArgs []string) error {
 	outputResults(diffs)
 
 	if filename != "" {
-		output.PrintToStdErr("Computing filename diffs")
+		output.PrintToStdErr("Computing filename diffs\n")
 		err := diffFile(imageMap[image1Arg], imageMap[image2Arg])
 		if err != nil {
 			return err

differs/differs.go

@@ -42,12 +42,13 @@ type Analyzer interface {
 }
 
 var Analyzers = map[string]Analyzer{
-	"history": HistoryAnalyzer{},
-	"file":    FileAnalyzer{},
-	"apt":     AptAnalyzer{},
-	"rpm":     RPMAnalyzer{},
-	"pip":     PipAnalyzer{},
-	"node":    NodeAnalyzer{},
+	"history":  HistoryAnalyzer{},
+	"metadata": MetadataAnalyzer{},
+	"file":     FileAnalyzer{},
+	"apt":      AptAnalyzer{},
+	"rpm":      RPMAnalyzer{},
+	"pip":      PipAnalyzer{},
+	"node":     NodeAnalyzer{},
 }
 
 func (req DiffRequest) GetDiff() (map[string]util.Result, error) {

differs/metadata_diff.go

@@ -0,0 +1,66 @@
+/*
+Copyright 2017 Google, Inc. All rights reserved.
+
+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 differs
+
+import (
+	pkgutil "github.com/GoogleCloudPlatform/container-diff/pkg/util"
+	"github.com/GoogleCloudPlatform/container-diff/util"
+)
+
+type MetadataAnalyzer struct {
+}
+
+type MetadataDiff struct {
+	Adds []string
+	Dels []string
+}
+
+func (a MetadataAnalyzer) Name() string {
+	return "MetadataAnalyzer"
+}
+
+func (a MetadataAnalyzer) Diff(image1, image2 pkgutil.Image) (util.Result, error) {
+	diff, err := getMetadataDiff(image1, image2)
+	return &util.MetadataDiffResult{
+		Image1:   image1.Source,
+		Image2:   image2.Source,
+		DiffType: "Metadata",
+		Diff:     diff,
+	}, err
+}
+
+func (a MetadataAnalyzer) Analyze(image pkgutil.Image) (util.Result, error) {
+	analysis := getMetadataList(image)
+	return &util.ListAnalyzeResult{
+		Image:       image.Source,
+		AnalyzeType: "Metadata",
+		Analysis:    analysis,
+	}, nil
+}
+
+func getMetadataDiff(image1, image2 pkgutil.Image) (MetadataDiff, error) {
+	m1 := getMetadataList(image1)
+	m2 := getMetadataList(image2)
+
+	adds := util.GetAdditions(m1, m2)
+	dels := util.GetDeletions(m1, m2)
+	return MetadataDiff{adds, dels}, nil
+}
+
+func getMetadataList(image pkgutil.Image) []string {
+	return image.Config.Config.AsList()
+}

pkg/util/image_prep_utils.go

@@ -20,6 +20,7 @@ import (
 	"archive/tar"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"io/ioutil"
 	"os"
 	"strings"
@@ -94,6 +95,18 @@ type ConfigObject struct {
 	Labels       map[string]string   `json:"Labels"`
 }
 
+func (c ConfigObject) AsList() []string {
+	return []string{
+		fmt.Sprintf("Env: %s", strings.Join(c.Env, ",")),
+		fmt.Sprintf("Entrypoint: %s", strings.Join(c.Entrypoint, ",")),
+		fmt.Sprintf("ExposedPorts: %v", c.ExposedPorts),
+		fmt.Sprintf("Cmd: %s", strings.Join(c.Cmd, ",")),
+		fmt.Sprintf("Volumes: %v", c.Volumes),
+		fmt.Sprintf("Workdir: %s", c.Workdir),
+		fmt.Sprintf("Labels: %v", c.Labels),
+	}
+}
+
 type ConfigSchema struct {
 	Config  ConfigObject       `json:"config"`
 	History []ImageHistoryItem `json:"history"`

tests/integration_test.go

@@ -39,6 +39,9 @@ const (
 	diffBase     = "gcr.io/gcp-runtimes/diff-base"
 	diffModified = "gcr.io/gcp-runtimes/diff-modified"
 
+	metadataBase     = "gcr.io/gcp-runtimes/metadata-base"
+	metadataModified = "gcr.io/gcp-runtimes/metadata-modified"
+
 	aptBase     = "gcr.io/gcp-runtimes/apt-base"
 	aptModified = "gcr.io/gcp-runtimes/apt-modified"
 
@@ -152,6 +155,14 @@ func TestDiffAndAnalysis(t *testing.T) {
 			differFlags:  []string{"--type=history"},
 			expectedFile: "hist_diff_expected.json",
 		},
+		{
+			description:  "metadata differ",
+			subcommand:   "diff",
+			imageA:       metadataBase,
+			imageB:       metadataModified,
+			differFlags:  []string{"--type=metadata"},
+			expectedFile: "metadata_diff_expected.json",
+		},
 		{
 			description:  "apt sorted differ",
 			subcommand:   "diff",

tests/metadata_diff_expected.json

@@ -0,0 +1,17 @@
+[
+  {
+    "Image1": "gcr.io/gcp-runtimes/metadata-base:latest",
+    "Image2": "gcr.io/gcp-runtimes/metadata-modified:latest",
+    "DiffType": "Metadata",
+    "Diff": {
+      "Adds": [
+        "Entrypoint: /entrypoint",
+        "ExposedPorts: map[1234/tcp:{}]"
+      ],
+      "Dels": [
+        "Entrypoint: ",
+        "ExposedPorts: map[1234/tcp:{} 4321/tcp:{}]"
+      ]
+    }
+  }
+]

util/diff_output_utils.go

@@ -172,6 +172,16 @@ func (r HistDiffResult) OutputText(diffType string, format string) error {
 	return TemplateOutputFromFormat(r, "HistDiff", format)
 }
 
+type MetadataDiffResult DiffResult
+
+func (r MetadataDiffResult) OutputStruct() interface{} {
+	return r
+}
+
+func (r MetadataDiffResult) OutputText(diffType string, format string) error {
+	return TemplateOutputFromFormat(r, "MetadataDiff", format)
+}
+
 type DirDiffResult DiffResult
 
 func (r DirDiffResult) OutputStruct() interface{} {

util/format_utils.go

@@ -32,6 +32,7 @@ var templates = map[string]string{
 	"SingleVersionPackageDiff":    SingleVersionDiffOutput,
 	"MultiVersionPackageDiff":     MultiVersionDiffOutput,
 	"HistDiff":                    HistoryDiffOutput,
+	"MetadataDiff":                MetadataDiffOutput,
 	"DirDiff":                     FSDiffOutput,
 	"FilenameDiff":                FilenameDiffOutput,
 	"ListAnalyze":                 ListAnalysisOutput,

util/template_utils.go

@@ -65,6 +65,17 @@ Docker history lines found only in {{.Image1}}:{{if not .Diff.Adds}} None{{else}
 
 Docker history lines found only in {{.Image2}}:{{if not .Diff.Dels}} None{{else}}{{block "list2" .Diff.Dels}}{{"\n"}}{{range .}}{{print "-" .}}{{"\n"}}{{end}}{{end}}{{end}}
 `
+
+const MetadataDiffOutput = `
+-----{{.DiffType}}-----
+
+Image metadata differences between {{.Image1}} and {{.Image2}}:
+
+{{.Image1}}{{if not .Diff.Adds}} None{{else}}{{block "list" .Diff.Adds}}{{"\n"}}{{range .}}{{print "-" .}}{{"\n"}}{{end}}{{end}}{{end}}
+
+{{.Image2}}{{if not .Diff.Dels}} None{{else}}{{block "list2" .Diff.Dels}}{{"\n"}}{{range .}}{{print "-" .}}{{"\n"}}{{end}}{{end}}{{end}}
+`
+
 const FilenameDiffOutput = `
 -----Diff of {{.Filename}}-----
 {{.Description}}