Fix invocation container always printing on stdout/stderr:

* the stderr was printed before the command top level error, so it was confusing
* the stdout needs to be captured by the render command to put it into a file if specified

Signed-off-by: Silvin Lubecki <silvin.lubecki@docker.com>

Author: silvin-lubecki

e2e/cnab_test.go

@@ -28,7 +28,7 @@ func TestCallCustomStatusAction(t *testing.T) {
 		{
 			name:           "missingCustomStatusAction",
 			exitCode:       1,
-			expectedOutput: "Status failed: action not defined for bundle",
+			expectedOutput: "status failed: action not defined for bundle",
 			cnab:           "cnab-without-status",
 		},
 	}

e2e/commands_test.go

@@ -53,6 +53,8 @@ func testRenderApp(appPath string, env ...string) func(*testing.T) {
 	return func(t *testing.T) {
 		cmd, cleanup := dockerCli.createTestCmd()
 		defer cleanup()
+		dir := fs.NewDir(t, "")
+		defer dir.Remove()
 
 		envParameters := map[string]string{}
 		data, err := ioutil.ReadFile(filepath.Join(appPath, "env.yml"))
@@ -64,8 +66,14 @@ func testRenderApp(appPath string, env ...string) func(*testing.T) {
 		}
 		cmd.Command = args
 		cmd.Env = append(cmd.Env, env...)
+		// Check rendering to stdout
 		result := icmd.RunCmd(cmd).Assert(t, icmd.Success)
 		assert.Assert(t, is.Equal(readFile(t, filepath.Join(appPath, "expected.txt")), result.Stdout()), "rendering mismatch")
+		// Checks rendering to a file
+		cmd.Command = append(cmd.Command, "--output="+dir.Join("actual.yaml"))
+		result = icmd.RunCmd(cmd).Assert(t, icmd.Success)
+
+		assert.Assert(t, is.Equal(readFile(t, filepath.Join(appPath, "expected.txt")), readFile(t, dir.Join("actual.yaml"))), "rendering mismatch")
 	}
 }
 

internal/commands/cnab.go

@@ -1,7 +1,9 @@
 package commands
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -90,13 +92,18 @@ func duffleHome() home.Home {
 }
 
 // prepareDriver prepares a driver per the user's request.
-func prepareDriver(dockerCli command.Cli, bindMount bindMount) (driver.Driver, error) {
+func prepareDriver(dockerCli command.Cli, bindMount bindMount, stdout io.Writer) (driver.Driver, *bytes.Buffer, error) {
 	driverImpl, err := driver.Lookup("docker")
 	if err != nil {
-		return driverImpl, err
+		return driverImpl, nil, err
 	}
+	errBuf := bytes.NewBuffer(nil)
 	if d, ok := driverImpl.(*driver.DockerDriver); ok {
 		d.SetDockerCli(dockerCli)
+		if stdout != nil {
+			d.SetContainerOut(stdout)
+		}
+		d.SetContainerErr(errBuf)
 		if bindMount.required {
 			d.AddConfigurationOptions(func(config *container.Config, hostConfig *container.HostConfig) error {
 				config.User = "0:0"
@@ -122,7 +129,7 @@ func prepareDriver(dockerCli command.Cli, bindMount bindMount) (driver.Driver, e
 		configurable.SetConfig(driverCfg)
 	}
 
-	return driverImpl, err
+	return driverImpl, errBuf, err
 }
 
 func getAppNameKind(name string) (string, nameKind) {
@@ -243,21 +250,20 @@ func isDockerHostLocal(host string) bool {
 	return host == "" || strings.HasPrefix(host, "unix://") || strings.HasPrefix(host, "npipe://")
 }
 
-func prepareCustomAction(actionName string, dockerCli command.Cli, appname string,
-	registryOpts registryOptions, pullOpts pullOptions, paramsOpts parametersOptions) (*action.RunCustom, *claim.Claim, error) {
-	defer muteDockerCli(dockerCli)()
+func prepareCustomAction(actionName string, dockerCli command.Cli, appname string, stdout io.Writer,
+	registryOpts registryOptions, pullOpts pullOptions, paramsOpts parametersOptions) (*action.RunCustom, *claim.Claim, *bytes.Buffer, error) {
 
 	c, err := claim.New(actionName)
 	if err != nil {
-		return nil, nil, err
+		return nil, nil, nil, err
 	}
-	driverImpl, err := prepareDriver(dockerCli, bindMount{})
+	driverImpl, errBuf, err := prepareDriver(dockerCli, bindMount{}, stdout)
 	if err != nil {
-		return nil, nil, err
+		return nil, nil, nil, err
 	}
 	bundle, err := resolveBundle(dockerCli, appname, pullOpts.pull, registryOpts.insecureRegistries)
 	if err != nil {
-		return nil, nil, err
+		return nil, nil, nil, err
 	}
 	c.Bundle = bundle
 
@@ -266,13 +272,13 @@ func prepareCustomAction(actionName string, dockerCli command.Cli, appname strin
 		withCommandLineParameters(paramsOpts.overrides),
 	)
 	if err != nil {
-		return nil, nil, err
+		return nil, nil, nil, err
 	}
 	c.Parameters = parameters
 
 	a := &action.RunCustom{
 		Action: internal.Namespace + actionName,
 		Driver: driverImpl,
 	}
-	return a, c, nil
+	return a, c, errBuf, nil
 }

internal/commands/inspect.go

@@ -1,9 +1,10 @@
 package commands
 
 import (
+	"fmt"
+
 	"github.com/docker/cli/cli"
 	"github.com/docker/cli/cli/command"
-	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
 
@@ -30,9 +31,13 @@ func inspectCmd(dockerCli command.Cli) *cobra.Command {
 }
 
 func runInspect(dockerCli command.Cli, appname string, opts inspectOptions) error {
-	a, c, err := prepareCustomAction("inspect", dockerCli, appname, opts.registryOptions, opts.pullOptions, opts.parametersOptions)
+	defer muteDockerCli(dockerCli)()
+	a, c, errBuf, err := prepareCustomAction("inspect", dockerCli, appname, nil, opts.registryOptions, opts.pullOptions, opts.parametersOptions)
 	if err != nil {
 		return err
 	}
-	return errors.Wrap(a.Run(c, nil, dockerCli.Out()), "Inspect failed")
+	if err := a.Run(c, nil, nil); err != nil {
+		return fmt.Errorf("inspect failed: %s", errBuf)
+	}
+	return nil
 }

internal/commands/install.go

@@ -98,7 +98,7 @@ func runInstall(dockerCli command.Cli, appname string, opts installOptions) erro
 		return err
 	}
 
-	driverImpl, err := prepareDriver(dockerCli, bind)
+	driverImpl, errBuf, err := prepareDriver(dockerCli, bind, nil)
 	if err != nil {
 		return err
 	}
@@ -129,7 +129,7 @@ func runInstall(dockerCli command.Cli, appname string, opts installOptions) erro
 	// so any installation needs a clean uninstallation.
 	err2 := claimStore.Store(*c)
 	if err != nil {
-		return fmt.Errorf("install failed: %v", err)
+		return fmt.Errorf("install failed: %s", errBuf)
 	}
 	return err2
 }

internal/commands/render.go

@@ -1,13 +1,14 @@
 package commands
 
 import (
+	"bytes"
+	"fmt"
 	"io"
 	"os"
 
 	"github.com/docker/app/internal"
 	"github.com/docker/cli/cli"
 	"github.com/docker/cli/cli/command"
-	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
 
@@ -41,21 +42,26 @@ func renderCmd(dockerCli command.Cli) *cobra.Command {
 }
 
 func runRender(dockerCli command.Cli, appname string, opts renderOptions) error {
-	a, c, err := prepareCustomAction("render", dockerCli, appname, opts.registryOptions, opts.pullOptions, opts.parametersOptions)
+	defer muteDockerCli(dockerCli)()
+	outBuf := bytes.NewBuffer(nil)
+	a, c, errBuf, err := prepareCustomAction("render", dockerCli, appname, outBuf, opts.registryOptions, opts.pullOptions, opts.parametersOptions)
 	if err != nil {
 		return err
 	}
 	c.Parameters[internal.Namespace+"render-format"] = opts.formatDriver
 
-	var writer io.Writer = dockerCli.Out()
+	if err := a.Run(c, nil, nil); err != nil {
+		return fmt.Errorf("render failed: %s", errBuf)
+	}
+	var w io.Writer = os.Stdout
 	if opts.renderOutput != "-" {
 		f, err := os.Create(opts.renderOutput)
 		if err != nil {
 			return err
 		}
 		defer f.Close()
-		writer = f
+		w = f
 	}
-	err = a.Run(c, nil, writer)
-	return errors.Wrap(err, "Render failed")
+	fmt.Fprintf(w, outBuf.String())
+	return nil
 }

internal/commands/status.go

@@ -1,14 +1,15 @@
 package commands
 
 import (
+	"fmt"
+
 	"github.com/deislabs/duffle/pkg/action"
 	"github.com/deislabs/duffle/pkg/claim"
 	"github.com/deislabs/duffle/pkg/credentials"
 	"github.com/deislabs/duffle/pkg/utils/crud"
 	"github.com/docker/app/internal"
 	"github.com/docker/cli/cli"
 	"github.com/docker/cli/cli/command"
-	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
 
@@ -42,7 +43,7 @@ func runStatus(dockerCli command.Cli, claimName string, opts credentialOptions)
 	if err != nil {
 		return err
 	}
-	driverImpl, err := prepareDriver(dockerCli, bind)
+	driverImpl, errBuf, err := prepareDriver(dockerCli, bind, nil)
 	if err != nil {
 		return err
 	}
@@ -57,6 +58,8 @@ func runStatus(dockerCli command.Cli, claimName string, opts credentialOptions)
 		Action: internal.Namespace + "status",
 		Driver: driverImpl,
 	}
-	err = status.Run(&c, creds, dockerCli.Out())
-	return errors.Wrap(err, "Status failed")
+	if err := status.Run(&c, creds, dockerCli.Out()); err != nil {
+		return fmt.Errorf("status failed: %s\n%s", err, errBuf)
+	}
+	return nil
 }

internal/commands/uninstall.go

@@ -42,7 +42,7 @@ func runUninstall(dockerCli command.Cli, claimName string, opts credentialOption
 	if err != nil {
 		return err
 	}
-	driverImpl, err := prepareDriver(dockerCli, bind)
+	driverImpl, errBuf, err := prepareDriver(dockerCli, bind, nil)
 	if err != nil {
 		return err
 	}
@@ -63,5 +63,5 @@ func runUninstall(dockerCli command.Cli, claimName string, opts credentialOption
 	if err2 := claimStore.Store(c); err2 != nil {
 		fmt.Fprintf(dockerCli.Err(), "failed to update claim: %s\n", err2)
 	}
-	return err
+	return fmt.Errorf("uninstall failed: %s", errBuf)
 }

internal/commands/upgrade.go

@@ -67,7 +67,7 @@ func runUpgrade(dockerCli command.Cli, installationName string, opts upgradeOpti
 	if err != nil {
 		return err
 	}
-	driverImpl, err := prepareDriver(dockerCli, bind)
+	driverImpl, errBuf, err := prepareDriver(dockerCli, bind, nil)
 	if err != nil {
 		return err
 	}
@@ -84,7 +84,7 @@ func runUpgrade(dockerCli command.Cli, installationName string, opts upgradeOpti
 	err = u.Run(&c, creds, dockerCli.Out())
 	err2 := claimStore.Store(c)
 	if err != nil {
-		return fmt.Errorf("upgrade failed: %v", err)
+		return fmt.Errorf("upgrade failed: %s", errBuf)
 	}
 	return err2
 }