Always use the docker client

Author: r2d4

README.md

@@ -85,8 +85,6 @@ To get a JSON version of the container-diff output add a `-j` or `--json` flag.
 
 ```container-diff <img1> <img2> -j```
 
-To use the docker client instead of shelling out to your local docker daemon, add a `-e` or `--eng` flag.
-
 ```container-diff <img1> <img2> -e```
 
 To order files and packages by size (in descending order) when performing file system or package analyses/diffs, add a `-o` or `--order` flag.

cmd/analyze.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"errors"
+	"fmt"
 	"os"
 
 	"github.com/GoogleCloudPlatform/container-diff/differs"
@@ -19,9 +20,6 @@ var analyzeCmd = &cobra.Command{
 			glog.Error(err.Error())
 			os.Exit(1)
 		}
-
-		utils.SetDockerEngine(eng)
-
 		analyzeArgs := []string{}
 		allAnalyzers := getAllAnalyzers()
 		for _, name := range allAnalyzers {
@@ -52,7 +50,17 @@ func checkAnalyzeArgNum(args []string) (bool, error) {
 }
 
 func analyzeImage(imageArg string, analyzerArgs []string) error {
-	image, err := utils.ImagePrepper{imageArg}.GetImage()
+	cli, err := NewClient()
+	if err != nil {
+		return fmt.Errorf("Error getting docker client for differ: %s", err)
+	}
+	defer cli.Close()
+	ip := utils.ImagePrepper{
+		Source: imageArg,
+		Client: cli,
+	}
+
+	image, err := ip.GetImage()
 	if err != nil {
 		glog.Error(err.Error())
 		cleanupImage(image)

cmd/diff.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"errors"
+	"fmt"
 	"os"
 	"sync"
 
@@ -20,9 +21,6 @@ var diffCmd = &cobra.Command{
 			glog.Error(err.Error())
 			os.Exit(1)
 		}
-
-		utils.SetDockerEngine(eng)
-
 		analyzeArgs := []string{}
 		allAnalyzers := getAllAnalyzers()
 		for _, name := range allAnalyzers {
@@ -53,24 +51,36 @@ func checkDiffArgNum(args []string) (bool, error) {
 }
 
 func diffImages(image1Arg, image2Arg string, diffArgs []string) error {
+	cli, err := NewClient()
+	if err != nil {
+		return fmt.Errorf("Error getting docker client for differ: %s", err)
+	}
+	defer cli.Close()
 	var wg sync.WaitGroup
 	wg.Add(2)
 
 	glog.Infof("Starting diff on images %s and %s, using differs: %s", image1Arg, image2Arg, diffArgs)
 
 	var image1, image2 utils.Image
-	var err error
 	go func() {
 		defer wg.Done()
-		image1, err = utils.ImagePrepper{image1Arg}.GetImage()
+		ip := utils.ImagePrepper{
+			Source: image1Arg,
+			Client: cli,
+		}
+		image1, err = ip.GetImage()
 		if err != nil {
 			glog.Error(err.Error())
 		}
 	}()
 
 	go func() {
 		defer wg.Done()
-		image2, err = utils.ImagePrepper{image2Arg}.GetImage()
+		ip := utils.ImagePrepper{
+			Source: image2Arg,
+			Client: cli,
+		}
+		image2, err = ip.GetImage()
 		if err != nil {
 			glog.Error(err.Error())
 		}

cmd/root.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	goflag "flag"
 	"fmt"
@@ -10,6 +11,7 @@ import (
 	"sort"
 
 	"github.com/GoogleCloudPlatform/container-diff/utils"
+	"github.com/docker/docker/client"
 	"github.com/golang/glog"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
@@ -40,6 +42,16 @@ var RootCmd = &cobra.Command{
 	Long:  `Analyzes a single image or compares two images using the specifed analyzers/differs as indicated via flags (see documentation for available ones).`,
 }
 
+func NewClient() (*client.Client, error) {
+	cli, err := client.NewEnvClient()
+	if err != nil {
+		return nil, fmt.Errorf("Error getting docker client: %s", err)
+	}
+	cli.NegotiateAPIVersion(context.Background())
+
+	return cli, nil
+}
+
 func outputResults(resultMap map[string]utils.Result) {
 	// Outputs diff/analysis results in alphabetical order by analyzer name
 	sortedTypes := []string{}
@@ -145,7 +157,6 @@ func init() {
 
 func addSharedFlags(cmd *cobra.Command) {
 	cmd.Flags().BoolVarP(&json, "json", "j", false, "JSON Output defines if the diff should be returned in a human readable format (false) or a JSON (true).")
-	cmd.Flags().BoolVarP(&eng, "eng", "e", false, "By default the docker calls are shelled out locally, set this flag to use the Docker Engine Client (version compatibility required).")
 	cmd.Flags().BoolVarP(&pip, "pip", "p", false, "Set this flag to use the pip differ.")
 	cmd.Flags().BoolVarP(&node, "node", "n", false, "Set this flag to use the node differ.")
 	cmd.Flags().BoolVarP(&apt, "apt", "a", false, "Set this flag to use the apt differ.")

differs/historyDiff.go

@@ -9,6 +9,11 @@ import (
 type HistoryAnalyzer struct {
 }
 
+type HistDiff struct {
+	Adds []string
+	Dels []string
+}
+
 func (a HistoryAnalyzer) Diff(image1, image2 utils.Image) (utils.Result, error) {
 	diff, err := getHistoryDiff(image1, image2)
 	return &utils.HistDiffResult{
@@ -29,13 +34,13 @@ func (a HistoryAnalyzer) Analyze(image utils.Image) (utils.Result, error) {
 	return &result, nil
 }
 
-func getHistoryDiff(image1, image2 utils.Image) (utils.HistDiff, error) {
+func getHistoryDiff(image1, image2 utils.Image) (HistDiff, error) {
 	history1 := getHistoryList(image1.Config.History)
 	history2 := getHistoryList(image2.Config.History)
 
 	adds := utils.GetAdditions(history1, history2)
 	dels := utils.GetDeletions(history1, history2)
-	diff := utils.HistDiff{adds, dels}
+	diff := HistDiff{adds, dels}
 	return diff, nil
 }