update Part.Config() to mach spec, it takes a config and returns a config

cmd/snappy-go/cmd_config.go

@@ -43,5 +43,11 @@ func (x *cmdConfig) Execute(args []string) (err error) {
 	if snap == nil {
 		return fmt.Errorf("No snap: '%s' found", pkgname)
 	}
-	return snap.Config(input)
+	newConfig, err := snap.Config(input)
+	if err != nil {
+		return err
+	}
+	fmt.Println(newConfig)
+
+	return nil
 }

snappy/config.go

@@ -6,41 +6,26 @@ import (
 	"os/exec"
 	"path/filepath"
 	"strings"
-
-	"github.com/mvo5/goconfigparser"
 )
 
-func snapConfig(snapDir, rawConfig string) error {
+func snapConfig(snapDir, rawConfig string) (newConfig string, err error) {
 	configScript := filepath.Join(snapDir, "hooks", "config")
 	cmd := exec.Command(configScript)
 	stdin, err := cmd.StdinPipe()
 	if err != nil {
-		return err
+		return "", err
 	}
+
 	// meh, really golang?
 	go func() {
 		defer stdin.Close()
 		io.Copy(stdin, strings.NewReader(rawConfig))
 	}()
 
-	output, err := cmd.Output()
+	output, err := cmd.CombinedOutput()
 	if err != nil {
-		return err
+		return "", fmt.Errorf("config failed with: '%s'", output)
 	}
 
-	// check he output,
-	// FIXME: goyaml does fail for me for the output "ok: true" :(
-	cfg := goconfigparser.New()
-	cfg.AllowNoSectionHeader = true
-	if err := cfg.ReadString(string(output)); err != nil {
-		return err
-	}
-	v, err := cfg.Get("", "ok")
-	// FIXME: more clever bool conversion
-	if err != nil || v != "true" {
-		errorStr, _ := cfg.Get("", "error")
-		return fmt.Errorf("config: '%s' failed with: '%s'", configScript, errorStr)
-	}
-
-	return nil
+	return string(output), nil
 }

snappy/config_test.go

@@ -12,17 +12,20 @@ import (
 
 const configPassthroughScript = `#!/bin/sh
 
-# just dump out for the tes
-cat - > %s/config.out
+# temp location to store cfg
+CFG="%s/config.out"
 
-# return resul
-printf "ok: true\n"
+# just dump out for the tes
+cat - > $CFG
+
+# and config
+cat $CFG
 `
 
-const configErrorScript = `#!/bin/sh -ex
+const configErrorScript = `#!/bin/sh
 
-printf "ok: false\n"
-printf "error: some error\n"
+printf "error: some error"
+exit 1
 `
 
 const configYaml = `
@@ -48,18 +51,21 @@ func (s *SnapTestSuite) TestConfigSimple(c *C) {
 	snapDir, err := s.makeMockSnapWithConfig(c, mockConfig)
 	c.Assert(err, IsNil)
 
-	err = snapConfig(snapDir, configYaml)
+	newConfig, err := snapConfig(snapDir, configYaml)
 	c.Assert(err, IsNil)
 	content, err := ioutil.ReadFile(filepath.Join(s.tempdir, "config.out"))
 	c.Assert(err, IsNil)
 	c.Assert(content, DeepEquals, []byte(configYaml))
+	c.Assert(newConfig, Equals, configYaml)
 }
 
 func (s *SnapTestSuite) TestConfigError(c *C) {
 	snapDir, err := s.makeMockSnapWithConfig(c, configErrorScript)
 	c.Assert(err, IsNil)
 
-	err = snapConfig(snapDir, configYaml)
+	newConfig, err := snapConfig(snapDir, configYaml)
 	c.Assert(err, NotNil)
-	c.Assert(strings.HasSuffix(err.Error(), "failed with: 'some error'"), Equals, true)
+	c.Assert(newConfig, Equals, "")
+	fmt.Println(err)
+	c.Assert(strings.HasSuffix(err.Error(), "failed with: 'error: some error'"), Equals, true)
 }

snappy/parts.go

@@ -39,10 +39,13 @@ type Part interface {
 	InstalledSize() int
 	DownloadSize() int
 
-	// Action
+	// Install the snap
 	Install(pb ProgressMeter) error
+	// Uninstall the snap
 	Uninstall() error
-	Config(configuration []byte) error
+	// Config takes a yaml configuration and returns the full snap
+	// config with the changes. Note that "configuration" may be empty.
+	Config(configuration []byte) (newConfig string, err error)
 	// make a inactive part active
 	SetActive() error
 }

snappy/snapp.go

@@ -165,7 +165,7 @@ func (s *SnapPart) Uninstall() (err error) {
 }
 
 // Config is used to to configure the snap
-func (s *SnapPart) Config(configuration []byte) (err error) {
+func (s *SnapPart) Config(configuration []byte) (new string, err error) {
 	return snapConfig(s.basedir, string(configuration))
 }
 
@@ -335,8 +335,8 @@ func (s *RemoteSnapPart) Uninstall() (err error) {
 }
 
 // Config is used to to configure the snap
-func (s *RemoteSnapPart) Config(configuration []byte) (err error) {
-	return err
+func (s *RemoteSnapPart) Config(configuration []byte) (new string, err error) {
+	return "", err
 }
 
 // NeedsReboot returns true if the snap becomes active on the next reboot

snappy/systemimage.go

@@ -176,8 +176,10 @@ func (s *SystemImagePart) Uninstall() (err error) {
 }
 
 // Config is used to to configure the snap
-func (s *SystemImagePart) Config(configuration []byte) (err error) {
-	return err
+func (s *SystemImagePart) Config(configuration []byte) (new string, err error) {
+	// FIXME: do something special here and call
+	//        ubuntu-core-config
+	return "", err
 }
 
 // NeedsReboot returns true if the snap becomes active on the next reboot