Fix based on reviews

e2e/commands_test.go

@@ -115,8 +115,8 @@ func checkFileWarning(t *testing.T, goldenFile, composeData string) {
 	cmd.Dir = tmpDir.Path()
 	cmd.Command = dockerCli.Command("app", "init", "app-test",
 		"--compose-file", tmpDir.Join(internal.ComposeFileName))
-	stdOut := icmd.RunCmd(cmd).Assert(t, icmd.Success).Combined()
-	golden.Assert(t, stdOut, goldenFile)
+	stdErr := icmd.RunCmd(cmd).Assert(t, icmd.Success).Stderr()
+	golden.Assert(t, stdErr, goldenFile)
 }
 
 func TestInitWarningEnvFiles(t *testing.T) {

e2e/testdata/init-output-warning-multiple-envfiles.golden

@@ -1,3 +1,2 @@
-"env_file: myenv1.env" entry of service "nginx" will NOT be copied automatically! Please, copy the file inside the application folder and update your compose file referring to it.
-"env_file: myenv2.env" entry of service "nginx" will NOT be copied automatically! Please, copy the file inside the application folder and update your compose file referring to it.
-Created "app-test.dockerapp"
+nginx.env_file "myenv1.env" will not be copied into app-test.dockerapp. Please copy it manually and update the path accordingly in the compose file.
+nginx.env_file "myenv2.env" will not be copied into app-test.dockerapp. Please copy it manually and update the path accordingly in the compose file.

e2e/testdata/init-output-warning-single-envfile.golden

@@ -1,2 +1 @@
-"env_file: myenv1.env" entry of service "nginx" will NOT be copied automatically! Please, copy the file inside the application folder and update your compose file referring to it.
-Created "app-test.dockerapp"
+nginx.env_file "myenv1.env" will not be copied into app-test.dockerapp. Please copy it manually and update the path accordingly in the compose file.

internal/commands/init.go

@@ -21,7 +21,7 @@ func initCmd(dockerCli command.Cli) *cobra.Command {
 $ docker app init myapp --compose-file docker-compose.yml`,
 		Args: cli.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			created, err := packager.Init(args[0], initComposeFile)
+			created, err := packager.Init(dockerCli.Err(), args[0], initComposeFile)
 			if err != nil {
 				return err
 			}

internal/packager/init.go

@@ -3,6 +3,7 @@ package packager
 import (
 	"bytes"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	"os/user"
@@ -27,7 +28,7 @@ import (
 // Init is the entrypoint initialization function.
 // It generates a new application definition based on the provided parameters
 // and returns the path to the created application definition.
-func Init(name string, composeFile string) (string, error) {
+func Init(errWriter io.Writer, name string, composeFile string) (string, error) {
 	if err := internal.ValidateAppName(name); err != nil {
 		return "", err
 	}
@@ -48,7 +49,7 @@ func Init(name string, composeFile string) (string, error) {
 	if composeFile == "" {
 		err = initFromScratch(name)
 	} else {
-		err = initFromComposeFile(name, composeFile)
+		err = initFromComposeFile(errWriter, name, composeFile)
 	}
 	if err != nil {
 		return "", err
@@ -95,29 +96,30 @@ func getEnvFiles(svcName string, envFileEntry interface{}) ([]string, error) {
 	return envFiles, nil
 }
 
-func checkEnvFiles(cfgMap map[string]interface{}) error {
+func checkEnvFiles(errWriter io.Writer, appName string, cfgMap map[string]interface{}) error {
 	services := cfgMap["services"]
 	servicesMap, ok := services.(map[string]interface{})
 	if !ok {
-		return fmt.Errorf("could not process the yaml file")
+		return fmt.Errorf("invalid Compose file")
 	}
 	for svcName, svc := range servicesMap {
 		svcContent, ok := svc.(map[string]interface{})
 		if !ok {
-			return fmt.Errorf("could not process the yaml file")
+			return fmt.Errorf("invalid service %q", svcName)
 		}
 		envFileEntry, ok := svcContent["env_file"]
 		if !ok {
 			continue
 		}
 		envFiles, err := getEnvFiles(svcName, envFileEntry)
 		if err != nil {
-			return errors.Wrap(err, "could not process the yaml file")
+			return errors.Wrap(err, "invalid Compose file")
 		}
 		for _, envFilePath := range envFiles {
-			fmt.Printf("\"env_file: %s\" entry of service %q will NOT be copied automatically! "+
-				"Please, copy the file inside the application folder and update your compose file "+
-				"referring to it.\n", envFilePath, svcName)
+			fmt.Fprintf(errWriter,
+				"%s.env_file %q will not be copied into %s.dockerapp. "+
+					"Please copy it manually and update the path accordingly in the compose file.\n",
+				svcName, envFilePath, appName)
 		}
 	}
 	return nil
@@ -152,14 +154,14 @@ func getParamsFromDefaultEnvFile(composeFile string, composeRaw []byte) (map[str
 	return params, needsFilling, nil
 }
 
-func initFromComposeFile(name string, composeFile string) error {
+func initFromComposeFile(errWriter io.Writer, name string, composeFile string) error {
 	logrus.Debugf("Initializing from compose file %s", composeFile)
 
 	dirName := internal.DirNameFromAppName(name)
 
 	composeRaw, err := ioutil.ReadFile(composeFile)
 	if err != nil {
-		return errors.Wrap(err, "failed to read compose file")
+		return errors.Wrapf(err, "failed to read compose file %q", composeFile)
 	}
 	cfgMap, err := composeloader.ParseYAML(composeRaw)
 	if err != nil {
@@ -168,7 +170,7 @@ func initFromComposeFile(name string, composeFile string) error {
 	if err := checkComposeFileVersion(cfgMap); err != nil {
 		return err
 	}
-	if err := checkEnvFiles(cfgMap); err != nil {
+	if err := checkEnvFiles(errWriter, name, cfgMap); err != nil {
 		return err
 	}
 	params, needsFilling, err := getParamsFromDefaultEnvFile(composeFile, composeRaw)

internal/packager/init_test.go

@@ -32,7 +32,7 @@ services:
 	)
 	defer dir.Remove()
 
-	err := initFromComposeFile(dir.Join(appName), inputDir.Join(internal.ComposeFileName))
+	err := initFromComposeFile(nil, dir.Join(appName), inputDir.Join(internal.ComposeFileName))
 	assert.NilError(t, err)
 
 	manifest := fs.Expected(
@@ -73,7 +73,7 @@ services:
 	)
 	defer dir.Remove()
 
-	err := initFromComposeFile(dir.Join(appName), inputDir.Join(internal.ComposeFileName))
+	err := initFromComposeFile(nil, dir.Join(appName), inputDir.Join(internal.ComposeFileName))
 	assert.NilError(t, err)
 
 	const expectedParameters = `ports:
@@ -108,7 +108,7 @@ services:
 }
 
 func TestInitFromInvalidComposeFile(t *testing.T) {
-	err := initFromComposeFile("my.dockerapp", "doesnotexist")
+	err := initFromComposeFile(nil, "my.dockerapp", "doesnotexist")
 	assert.ErrorContains(t, err, "failed to read")
 }
 
@@ -131,7 +131,7 @@ services:
 	)
 	defer dir.Remove()
 
-	err := initFromComposeFile(dir.Join(appName), inputDir.Join(internal.ComposeFileName))
+	err := initFromComposeFile(nil, dir.Join(appName), inputDir.Join(internal.ComposeFileName))
 	assert.ErrorContains(t, err, "unsupported Compose file version")
 }
 
@@ -151,7 +151,7 @@ nginx:
 	)
 	defer dir.Remove()
 
-	err := initFromComposeFile(dir.Join(appName), inputDir.Join(internal.ComposeFileName))
+	err := initFromComposeFile(nil, dir.Join(appName), inputDir.Join(internal.ComposeFileName))
 	assert.ErrorContains(t, err, "unsupported Compose file version")
 }