adds pack set-default-stack command

[#38]
buildpacks · Oct 11, 2018 · 1eb3543 · 1eb3543
1 parent 0708d2a
commit 1eb3543
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Showing 4 changed files with 107 additions and 0 deletions.
diff --git a/acceptance/acceptance_test.go b/acceptance/acceptance_test.go
@@ -357,6 +357,40 @@ func testPack(t *testing.T, when spec.G, it spec.S) {
 		})
 	}, spec.Parallel(), spec.Report(report.Terminal{}))
 
+	when("pack update-stack", func() {
+		type config struct {
+			DefaultStackID string  `toml:"default-stack-id"`
+		}
+
+		it.Before(func() {
+			cmd := exec.Command(pack, "add-stack", "my.custom.stack", "--run-image", "my-org/run", "--build-image", "my-org/build")
+			cmd.Env = append(os.Environ(), "HOME="+homeDir)
+			output, err := cmd.CombinedOutput()
+			if err != nil {
+				t.Fatalf("add-stack command failed: %s: %s", output, err)
+			}
+		})
+
+		it("sets the default-stack-id in ~/.pack/config.toml", func() {
+			cmd := exec.Command(
+				pack,
+				"set-default-stack",
+				"my.custom.stack",
+			)
+			cmd.Env = append(os.Environ(), "HOME="+homeDir)
+			output, err := cmd.CombinedOutput()
+			if err != nil {
+				t.Fatalf("set-default-stack command failed: %s: %s", output, err)
+			}
+			assertEq(t, string(output), "my.custom.stack is now the default stack\n")
+
+			var config config
+			_, err = toml.DecodeFile(filepath.Join(homeDir, ".pack", "config.toml"), &config)
+			assertNil(t, err)
+			assertEq(t, config.DefaultStackID, "my.custom.stack")
+		})
+	}, spec.Parallel(), spec.Report(report.Terminal{}))
+
 	when("pack delete-stack", func() {
 		type config struct {
 			Stacks []struct {

diff --git a/cmd/pack/main.go b/cmd/pack/main.go
@@ -25,6 +25,7 @@ func main() {
 		addStackCommand,
 		updateStackCommand,
 		deleteStackCommand,
+		setDefaultStackCommand,
 	} {
 		rootCmd.AddCommand(f())
 	}
@@ -160,6 +161,25 @@ func addStackCommand() *cobra.Command {
 	return addStackCommand
 }
 
+func setDefaultStackCommand() *cobra.Command {
+	return &cobra.Command{
+		Use:  "set-default-stack <stack-name>",
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			cfg, err := config.New(filepath.Join(os.Getenv("HOME"), ".pack"))
+			if err != nil {
+				return err
+			}
+			err = cfg.SetDefaultStack(args[0])
+			if err != nil {
+				return err
+			}
+			fmt.Printf("%s is now the default stack\n", args[0])
+			return nil
+		},
+	}
+}
+
 func updateStackCommand() *cobra.Command {
 	flags := struct {
 		BuildImages []string

diff --git a/config/config.go b/config/config.go
@@ -126,6 +126,15 @@ func (c *Config) Delete(stackID string) error {
 	}
 	return fmt.Errorf(`"%s" does not exist. Please pass in a valid stack ID.`, stackID)
 }
+func (c *Config) SetDefaultStack(stackID string) error {
+	for _, s := range c.Stacks {
+		if s.ID == stackID {
+			c.DefaultStackID = stackID
+			return c.save()
+		}
+	}
+	return fmt.Errorf(`"%s" does not exist. Please pass in a valid stack ID.`, stackID)
+}
 
 func ImageByRegistry(registry string, images []string) (string, error) {
 	if len(images) == 0 {

diff --git a/config/config_test.go b/config/config_test.go
@@ -201,6 +201,40 @@ default-stack-id = "my.stack"
 		})
 	})
 
+	when("Config#SetDefaultStack", func() {
+		var subject *config.Config
+		it.Before(func() {
+			assertNil(t, ioutil.WriteFile(filepath.Join(tmpDir, "config.toml"), []byte(`
+default-stack-id = "old.default.stack"
+[[stacks]]
+  id = "some.stack"
+`), 0666))
+			var err error
+			subject, err = config.New(tmpDir)
+			assertNil(t, err)
+		})
+
+		when("the stack exists", func() {
+			it("sets the default-stack-id", func() {
+				err := subject.SetDefaultStack("some.stack")
+				assertNil(t, err)
+				b, err := ioutil.ReadFile(filepath.Join(tmpDir, "config.toml"))
+				assertNil(t, err)
+				assertContains(t, string(b), `default-stack-id = "some.stack"`)
+			})
+		})
+
+		when("the stack doesn't exist", func() {
+			it("returns an error and leaves the original default", func() {
+				err := subject.SetDefaultStack("some.missing.stack")
+				assertError(t, err, `"some.missing.stack" does not exist. Please pass in a valid stack ID.`)
+				b, err := ioutil.ReadFile(filepath.Join(tmpDir, "config.toml"))
+				assertNil(t, err)
+				assertContains(t, string(b), `default-stack-id = "old.default.stack"`)
+			})
+		})
+	})
+
 	when("Config#Add", func() {
 		var subject *config.Config
 		it.Before(func() {
@@ -475,3 +509,13 @@ func assertEq(t *testing.T, actual, expected interface{}) {
 		t.Fatal(diff)
 	}
 }
+
+func assertError(t *testing.T, actual error, expected string) {
+	t.Helper()
+	if actual == nil {
+		t.Fatalf("Expected an error but got nil")
+	}
+	if actual.Error() != expected {
+		t.Fatalf(`Expected error to equal "%s", got "%s"`, expected, actual.Error())
+	}
+}