Change diff command properly to send messages over channels

cmd-diff.go

@@ -1,5 +1,5 @@
 /*
- * Minio Client (C) 2014, 2015 Minio, Inc.
+ * Minio Client (C) 2015 Minio, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,10 +17,7 @@
 package main
 
 import (
-	"path/filepath"
-
 	"github.com/minio/cli"
-	"github.com/minio/mc/pkg/client"
 	"github.com/minio/mc/pkg/console"
 	"github.com/minio/minio/pkg/iodine"
 )
@@ -73,141 +70,55 @@ func runDiffCmd(ctx *cli.Context) {
 		}
 	}
 
-	doDiffCmd(firstURL, secondURL)
+	for diff := range doDiffCmd(firstURL, secondURL) {
+		if diff.err != nil {
+			console.Fatalf(diff.message)
+		}
+		console.Infof(diff.message)
+	}
 }
 
-// urlJoinPath - Join a path to existing URL
+func doDiffInRoutine(firstURL, secondURL string, ch chan diff) {
-func urlJoinPath(urlStr string, path string) (newURLStr string, err error) {
+	_, firstContent, err := url2Stat(firstURL)
-	u, err := client.Parse(urlStr)
 	if err != nil {
-		return "", iodine.New(err, nil)
+		ch <- diff{
+			message: "Failed to stat " + firstURL + ". Reason: [" + iodine.ToError(err).Error() + "]\n",
+			err:     iodine.New(err, nil),
+		}
+		return
 	}
-
+	_, secondContent, err := url2Stat(secondURL)
-	u.Path = filepath.Join(u.Path, path)
+	if err != nil {
-	newURLStr = u.String()
+		ch <- diff{
-	return newURLStr, nil
+			message: "Failed to stat " + secondURL + ". Reason: [" + iodine.ToError(err).Error() + "]\n",
+			err:     iodine.New(err, nil),
+		}
+		return
+	}
+	if firstContent.Type.IsRegular() {
+		if !secondContent.Type.IsRegular() {
+			ch <- diff{
+				message: firstURL + " and " + secondURL + " differs in type.\n",
+				err:     nil,
+			}
+		}
+		doDiffObjects(firstURL, secondURL, ch)
+	}
+	if firstContent.Type.IsDir() {
+		if !secondContent.Type.IsDir() {
+			ch <- diff{
+				message: firstURL + " and " + secondURL + " differs in type.\n",
+				err:     nil,
+			}
+		}
+		doDiffDirs(firstURL, secondURL, ch)
+	}
+	close(ch)
 }
 
 // doDiffCmd - Execute the diff command
-func doDiffCmd(firstURL string, secondURL string) {
+func doDiffCmd(firstURL, secondURL string) <-chan diff {
-	_, firstContent, err := URL2Stat(firstURL)
+	ch := make(chan diff)
-	if err != nil {
+	go doDiffInRoutine(firstURL, secondURL, ch)
-		console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", firstURL, iodine.ToError(err))
+	return ch
-	}
-
-	_, secondContent, err := URL2Stat(secondURL)
-	if err != nil {
-		console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", secondURL, iodine.ToError(err))
-	}
-
-	if firstContent.Type.IsRegular() {
-		if !secondContent.Type.IsRegular() {
-			console.Infof("‘%s’ and ‘%s’ differs in type.\n", firstURL, secondURL)
-			return
-		}
-		doDiffCmdObjects(firstURL, secondURL)
-		return
-	}
-
-	if firstContent.Type.IsDir() {
-		if !secondContent.Type.IsDir() {
-			console.Infof("‘%s’ and ‘%s’ differs in type.\n", firstURL, secondURL)
-			return
-		}
-		doDiffCmdDirs(firstURL, secondURL)
-		return
-	}
-
-	console.Fatalf("‘%s’ is of unknown type.\n", firstURL)
-}
-
-// doDiffCmdObjects - Diff two object URLs
-func doDiffCmdObjects(firstURL string, secondURL string) {
-	if firstURL == secondURL { // kind of lame :p
-		return
-	}
-	_, firstContent, err := URL2Stat(firstURL)
-	if err != nil {
-		console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", firstURL, iodine.ToError(err))
-	}
-
-	_, secondContent, err := URL2Stat(secondURL)
-	if err != nil {
-		console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", secondURL, iodine.ToError(err))
-	}
-
-	if firstContent.Type.IsRegular() {
-		if !secondContent.Type.IsRegular() {
-			console.Infof("‘%s’ and ‘%s’ differs in type.\n", firstURL, secondURL)
-			return
-		}
-	} else {
-		console.Fatalf("‘%s’ is not an object. Please report this bug with ‘--debug’ option\n.", firstURL)
-	}
-
-	if firstContent.Size != secondContent.Size {
-		console.Infof("‘%s’ and ‘%s’ differs in size.\n", firstURL, secondURL)
-	}
-}
-
-// doDiffCmdDirs - Diff two Dir URLs
-func doDiffCmdDirs(firstURL string, secondURL string) {
-	firstClnt, firstContent, err := URL2Stat(firstURL)
-	if err != nil {
-		console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", firstURL, iodine.ToError(err))
-	}
-
-	_, secondContent, err := URL2Stat(secondURL)
-	if err != nil {
-		console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", secondURL, iodine.ToError(err))
-	}
-
-	if firstContent.Type.IsDir() {
-		if !secondContent.Type.IsDir() {
-			console.Infof("‘%s’ and ‘%s’ differs in type.\n", firstURL, secondURL)
-			return
-		}
-	} else {
-		console.Fatalf("‘%s’ is not a directory. Please report this bug with ‘--debug’ option\n.", firstURL)
-	}
-
-	for contentCh := range firstClnt.List() {
-		if contentCh.Err != nil {
-			console.Fatalf("Failed to list ‘%s’. Reason: [%s].\n", firstURL, iodine.ToError(contentCh.Err))
-		}
-
-		newFirstURL, err := urlJoinPath(firstURL, contentCh.Content.Name)
-		if err != nil {
-			console.Fatalf("Unable to construct new URL from ‘%s’ using ‘%s’. Reason: [%s].\n", firstURL, contentCh.Content.Name, iodine.ToError(err))
-		}
-
-		newSecondURL, err := urlJoinPath(secondURL, contentCh.Content.Name)
-		if err != nil {
-			console.Fatalf("Unable to construct new URL from ‘%s’ using ‘%s’. Reason: [%s].\n", secondURL, contentCh.Content.Name, iodine.ToError(err))
-		}
-
-		_, newFirstContent, err := URL2Stat(newFirstURL)
-		if err != nil {
-			console.Fatalf("Failed to stat ‘%s’. Reason: [%s].\n", newFirstURL, iodine.ToError(err))
-		}
-
-		_, newSecondContent, err := URL2Stat(newSecondURL)
-		if err != nil {
-			console.Infof("‘%s’ only in ‘%s’.\n", filepath.Base(newFirstContent.Name), firstURL)
-			continue
-		}
-
-		if newFirstContent.Type.IsDir() {
-			if !newSecondContent.Type.IsDir() {
-				console.Infof("‘%s’ and ‘%s’ differs in type.\n", newFirstURL, newSecondURL)
-				continue
-			}
-		} else if newFirstContent.Type.IsRegular() {
-			if !newSecondContent.Type.IsRegular() {
-				console.Infof("‘%s’ and ‘%s’ differs in type.\n", newFirstURL, newSecondURL)
-				continue
-			}
-			doDiffCmdObjects(newFirstURL, newSecondURL)
-		}
-	} // End of for-loop
 }

common-methods.go

@@ -75,8 +75,8 @@ func getNewClient(urlStr string, auth *hostConfig, debug bool) (clnt client.Clie
 	return nil, iodine.New(errInvalidURL{url: urlStr}, nil)
 }
 
-// URL2Stat - Returns client, config and its stat Content from the URL
+// url2Stat - Returns client, config and its stat Content from the URL
-func URL2Stat(urlStr string) (client client.Client, content *client.Content, err error) {
+func url2Stat(urlStr string) (client client.Client, content *client.Content, err error) {
 	config, err := getHostConfig(urlStr)
 	if err != nil {
 		return nil, nil, iodine.New(err, map[string]string{"URL": urlStr})

cp-url.go

@@ -421,7 +421,7 @@ func prepareCopyURLs(sourceURLs []string, targetURL string) <-chan *cpURLs {
 				cpURLsCh <- cpURLs
 			}
 		default:
-			cpURLsCh <- &cpURLs{Error: iodine.New(errors.New("Invalid arguments."), nil)}
+			cpURLsCh <- &cpURLs{Error: iodine.New(errInvalidArgument{}, nil)}
 		}
 	}(sourceURLs, targetURL, cpURLsCh)
 

diff.go

@@ -0,0 +1,182 @@
+/*
+ * Minio Client (C) 2015 Minio, Inc.
+ *
+ * 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 main
+
+import (
+	"path/filepath"
+
+	"github.com/minio/mc/pkg/client"
+	"github.com/minio/minio/pkg/iodine"
+)
+
+type diff struct {
+	message string
+	err     error
+}
+
+// urlJoinPath Join a path to existing URL
+func urlJoinPath(urlStr, path string) (newURLStr string, err error) {
+	u, err := client.Parse(urlStr)
+	if err != nil {
+		return "", iodine.New(err, nil)
+	}
+
+	u.Path = filepath.Join(u.Path, path)
+	newURLStr = u.String()
+	return newURLStr, nil
+}
+
+// doDiffObjects - Diff two object URLs
+func doDiffObjects(firstURL, secondURL string, ch chan diff) {
+	if firstURL == secondURL {
+		return
+	}
+	_, firstContent, err := url2Stat(firstURL)
+	if err != nil {
+		ch <- diff{
+			message: "Failed to stat ‘" + firstURL + "’ " + "Reason: [" + iodine.ToError(err).Error() + "].\n",
+			err:     iodine.New(err, nil),
+		}
+		return
+	}
+
+	_, secondContent, err := url2Stat(secondURL)
+	if err != nil {
+		ch <- diff{
+			message: "Failed to stat ‘" + secondURL + "’ " + "Reason: [" + iodine.ToError(err).Error() + "].\n",
+			err:     iodine.New(err, nil),
+		}
+		return
+	}
+
+	switch {
+	case firstContent.Type.IsRegular():
+		if !secondContent.Type.IsRegular() {
+			ch <- diff{
+				message: firstURL + " and " + secondURL + " differs in type.\n",
+				err:     nil,
+			}
+		}
+	default:
+		ch <- diff{
+			message: "‘" + firstURL + "’ is not an object. Please report this bug with ‘--debug’ option\n.",
+			err:     iodine.New(errNotAnObject{url: firstURL}, nil),
+		}
+	}
+
+	if firstContent.Size != secondContent.Size {
+		ch <- diff{
+			message: firstURL + " and " + secondURL + " differs in size.\n",
+			err:     nil,
+		}
+	}
+}
+
+// doDiffDirs - Diff two Dir URLs
+func doDiffDirs(firstURL, secondURL string, ch chan diff) {
+	firstClnt, firstContent, err := url2Stat(firstURL)
+	if err != nil {
+		ch <- diff{
+			message: "Failed to stat ‘" + firstURL + "’ ." + "Reason: [" + iodine.ToError(err).Error() + "].\n",
+			err:     iodine.New(err, nil),
+		}
+		return
+	}
+	_, secondContent, err := url2Stat(secondURL)
+	if err != nil {
+		ch <- diff{
+			message: "Failed to stat ‘" + secondURL + "’ ." + "Reason: [" + iodine.ToError(err).Error() + "].\n",
+			err:     iodine.New(err, nil),
+		}
+		return
+	}
+	switch {
+	case firstContent.Type.IsDir():
+		if !secondContent.Type.IsDir() {
+			ch <- diff{
+				message: firstURL + " and " + secondURL + " differs in type.\n",
+				err:     nil,
+			}
+		}
+	default:
+		ch <- diff{
+			message: "‘" + firstURL + "’ is not an object. Please report this bug with ‘--debug’ option\n.",
+			err:     iodine.New(errNotAnObject{url: firstURL}, nil),
+		}
+	}
+	for contentCh := range firstClnt.List() {
+		if contentCh.Err != nil {
+			ch <- diff{
+				message: "Failed to list ‘" + firstURL + "’. Reason: [" + iodine.ToError(contentCh.Err).Error() + "].\n",
+				err:     iodine.New(contentCh.Err, nil),
+			}
+			return
+		}
+		newFirstURL, err := urlJoinPath(firstURL, contentCh.Content.Name)
+		if err != nil {
+			ch <- diff{
+				message: "Unable to construct new URL from ‘" + firstURL + "’ using ‘" + contentCh.Content.Name + "’. Reason: [" + iodine.ToError(err).Error() + "].\n",
+				err:     iodine.New(err, nil),
+			}
+			return
+		}
+		newSecondURL, err := urlJoinPath(secondURL, contentCh.Content.Name)
+		if err != nil {
+			ch <- diff{
+				message: "Unable to construct new URL from ‘" + secondURL + "’ using ‘" + contentCh.Content.Name + "’. Reason: [" + iodine.ToError(err).Error() + "].\n",
+				err:     iodine.New(err, nil),
+			}
+			return
+		}
+		_, newFirstContent, err := url2Stat(newFirstURL)
+		if err != nil {
+			ch <- diff{
+				message: "Failed to stat ‘" + newFirstURL + "’. Reason: [" + iodine.ToError(err).Error() + "].\n",
+				err:     iodine.New(err, nil),
+			}
+			return
+
+		}
+		_, newSecondContent, err := url2Stat(newSecondURL)
+		if err != nil {
+			ch <- diff{
+				message: "‘" + filepath.Base(newFirstContent.Name) + "’ only in ‘" + firstURL + "’.\n",
+				err:     nil,
+			}
+			continue
+		}
+		switch {
+		case newFirstContent.Type.IsDir():
+			if !newSecondContent.Type.IsDir() {
+				ch <- diff{
+					message: newFirstURL + " and " + newSecondURL + " differs in type.\n",
+					err:     nil,
+				}
+				continue
+			}
+		case newFirstContent.Type.IsRegular():
+			if !newSecondContent.Type.IsRegular() {
+				ch <- diff{
+					message: newFirstURL + " and " + newSecondURL + " differs in type.\n",
+					err:     nil,
+				}
+				continue
+			}
+			doDiffObjects(newFirstURL, newSecondURL, ch)
+		}
+	} // End of for-loop
+}

errors.go

@@ -16,6 +16,14 @@
 
 package main
 
+type errNotAnObject struct {
+	url string
+}
+
+func (e errNotAnObject) Error() string {
+	return "Not an object " + e.url
+}
+
 type errInvalidACL struct {
 	acl string
 }
@@ -27,7 +35,7 @@ func (e errInvalidACL) Error() string {
 type errInvalidArgument struct{}
 
 func (e errInvalidArgument) Error() string {
-	return "Invalid argument"
+	return "Invalid argument."
 }
 
 type errUnsupportedScheme struct {

sync-url.go

@@ -16,11 +16,7 @@
 
 package main
 
-import (
+import "github.com/minio/minio/pkg/iodine"
-	"errors"
-
-	"github.com/minio/minio/pkg/iodine"
-)
 
 //
 //   NOTE: All the parse rules should reduced to A: Copy(Source, Target).
@@ -65,7 +61,7 @@ func prepareSyncURLs(sourceURL string, targetURLs []string) <-chan *cpURLs {
 					syncURLsCh <- syncURLs
 				}
 			default:
-				syncURLsCh <- &cpURLs{Error: iodine.New(errors.New("Invalid arguments."), nil)}
+				syncURLsCh <- &cpURLs{Error: iodine.New(errInvalidArgument{}, nil)}
 			}
 		}
 	}()