From 6d0d1920e16e172e3b075559582d4ebbab60f9d0 Mon Sep 17 00:00:00 2001
From: Chanwit Kaewkasi <chanwit@gmail.com>
Date: Fri, 25 Oct 2019 16:24:51 +0700
Subject: [PATCH] implement file ignore in the profile enable process

---
 cmd/wksctl/profile/constants/constants.go |  3 ++
 cmd/wksctl/profile/enable/enable.go       | 60 ++++++++++++++++++++++-
 cmd/wksctl/profile/enable/enable_test.go  | 45 +++++++++++++++++
 pkg/git/git.go                            |  4 +-
 4 files changed, 108 insertions(+), 4 deletions(-)
 create mode 100644 cmd/wksctl/profile/enable/enable_test.go

diff --git a/cmd/wksctl/profile/constants/constants.go b/cmd/wksctl/profile/constants/constants.go
index 2c544873..77b0739c 100644
--- a/cmd/wksctl/profile/constants/constants.go
+++ b/cmd/wksctl/profile/constants/constants.go
@@ -3,4 +3,7 @@ package constants
 const (
 	AppDevAlias   = "app-dev"
 	AppDevRepoURL = "git@github.com:weaveworks/eks-quickstart-app-dev"
+
+	// WKSctlIgnoreFilename is the ignore file recognized by wksctl
+	WKSctlIgnoreFilename = ".wksctlignore"
 )
diff --git a/cmd/wksctl/profile/enable/enable.go b/cmd/wksctl/profile/enable/enable.go
index 109226dd..1819adef 100644
--- a/cmd/wksctl/profile/enable/enable.go
+++ b/cmd/wksctl/profile/enable/enable.go
@@ -1,8 +1,13 @@
 package enable
 
 import (
+	"bufio"
 	"errors"
+	"fmt"
+	"io"
+	"os"
 	"path"
+	"regexp"
 
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
@@ -69,15 +74,20 @@ func profileEnableRun(params profileEnableFlags) error {
 	if err != nil {
 		return err
 	}
-	clonePath := path.Join(params.profileDir, hostName, repoName)
+	profilePath := path.Join(params.profileDir, hostName, repoName)
 
 	log.Info("Adding the profile to the local repository...")
-	err = git.SubtreeAdd(clonePath, repoURL, params.revision)
+	err = git.SubtreeAdd(profilePath, repoURL, params.revision)
 	if err != nil {
 		return err
 	}
 	log.Info("Added the profile to the local repository.")
 
+	// Detect and process the ignore file if found at the top most directory of the profile
+	if err := doIgnoreFiles(profilePath); err != nil {
+		return err
+	}
+
 	// The default behaviour is auto-commit and push
 	if params.push {
 		if err := git.Push(); err != nil {
@@ -87,3 +97,49 @@ func profileEnableRun(params profileEnableFlags) error {
 
 	return nil
 }
+
+func doIgnoreFiles(profilePath string) error {
+	ignoreFilePath := path.Join(profilePath, constants.WKSctlIgnoreFilename)
+	if _, err := os.Stat(ignoreFilePath); err == nil {
+		log.Infof("Ignoring files declared in %s...", constants.WKSctlIgnoreFilename)
+		file, err := os.Open(ignoreFilePath)
+		if err != nil {
+			return err
+		}
+		defer file.Close()
+		pathsToIgnores, err := parseDotIgnorefile(profilePath, file)
+		if err != nil {
+			return err
+		}
+		if err := removePathsFromGit(pathsToIgnores...); err != nil {
+			return err
+		}
+		log.Info("Ignored files successfully.")
+	}
+	return nil
+}
+
+func parseDotIgnorefile(dir string, reader io.Reader) ([]string, error) {
+	result := []string{}
+	scanner := bufio.NewScanner(reader)
+	re := regexp.MustCompile(`(?ms)^\s*(?P<pathToIgnore>[^\s#]+).*$`)
+	for scanner.Scan() {
+		groups := re.FindStringSubmatch(scanner.Text())
+		if len(groups) != 2 {
+			continue
+		}
+		pathToIgnore := groups[1]
+		result = append(result, path.Join(dir, pathToIgnore))
+	}
+	return result, nil
+}
+
+func removePathsFromGit(paths ...string) error {
+	if err := git.RmRecursive(paths...); err != nil {
+		return err
+	}
+	if err := git.Commit(fmt.Sprintf("Ignored files declared in %s", constants.WKSctlIgnoreFilename)); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/cmd/wksctl/profile/enable/enable_test.go b/cmd/wksctl/profile/enable/enable_test.go
new file mode 100644
index 00000000..4b4a07a2
--- /dev/null
+++ b/cmd/wksctl/profile/enable/enable_test.go
@@ -0,0 +1,45 @@
+package enable
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	ignoreFileFixture = `a
+b/
+ #c
+#d
+e
+f
+../g
+h..
+i # this is i
+ j/# this is j
+`
+)
+
+func TestParseDotIgnoreFile(t *testing.T) {
+	r := strings.NewReader(ignoreFileFixture)
+	lines, err := parseDotIgnorefile("", r)
+	assert.NoError(t, err, "parsing ignore file should not be error")
+	assert.Equal(t, 8, len(lines), "ignore file entries should be 8")
+	// Entry: 'b/' is resolved to 'b' by path.Join()
+	assert.Equal(t, []string{"a", "b", "e", "f", "../g", "h..", "i", "j"}, lines)
+}
+
+func TestParseDotIgnoreFileWithPrefix(t *testing.T) {
+	r := strings.NewReader(ignoreFileFixture)
+	lines, err := parseDotIgnorefile("profiles", r)
+	assert.NoError(t, err, "parsing ignore file should not be error")
+	assert.Equal(t, 8, len(lines), "ignore file entries should be 8")
+	// Note:
+	// - 'profiles/b/' is resolved to 'profiles/b'
+	// - 'profiles/../g' is resolved to 'g'
+	assert.Equal(t, []string{
+		"profiles/a", "profiles/b", "profiles/e",
+		"profiles/f", "g", "profiles/h..",
+		"profiles/i", "profiles/j"}, lines)
+}
diff --git a/pkg/git/git.go b/pkg/git/git.go
index 3b4b3acc..b720e3e0 100644
--- a/pkg/git/git.go
+++ b/pkg/git/git.go
@@ -22,8 +22,8 @@ func HasNoStagedChanges() error {
 	return errors.Wrap(gitExec("diff", "--staged", "--exit-code"), "repository contains staged changes")
 }
 
-func RmRecursive(path string) error {
-	return gitExec("rm", "-r", "--", path)
+func RmRecursive(paths ...string) error {
+	return gitExec(append([]string{"rm", "-r", "--"}, paths...)...)
 }
 
 func AddAll(path string) error {