// followGitSubmodule looks at a .git /file/ and tries to retrieve from inside
// it the gitdir value, which is supposed to indicate the location of the
// corresponding .git /directory/. Note: the gitdir value should point directly
// to the corresponding .git directory even in the case of nested submodules.
func followGitSubmodule(fs util.FileSystem, gitPath string) (string, error) {
f, err := os.Open(gitPath)
if err != nil {
return "", err
}
defer f.Close()
sc := bufio.NewScanner(f)
if sc.Scan() {
s := sc.Text()
if strings.HasPrefix(s, "gitdir: ") {
newGitPath := s[8:]
if !filepath.IsAbs(newGitPath) {
newGitPath = filepath.Join(filepath.Dir(gitPath), newGitPath)
}
fi, err := fs.Stat(newGitPath)
if err != nil && !os.IsNotExist(err) {
return "", err
}
if os.IsNotExist(err) || !fi.IsDir() {
return "", fmt.Errorf("gitdir link in .git file %q is invalid", gitPath)
}
return newGitPath, nil
}
}
return "", fmt.Errorf("unable to parse .git file %q", gitPath)
}
// isValidGitRepository checks to see if there is a git repository in the
// directory and if the repository is valid -- i.e. it has remotes or commits
func isValidGitRepository(fs util.FileSystem, dir string) (bool, error) {
gitPath := filepath.Join(strings.TrimPrefix(dir, "file://"), ".git")
fi, err := fs.Stat(gitPath)
if os.IsNotExist(err) {
// The directory is not a git repo, no error
return false, nil
}
if err != nil {
return false, err
}
if !fi.IsDir() {
gitPath, err = followGitSubmodule(fs, gitPath)
if err != nil {
return false, err
}
}
// Search the content of the .git directory for content
directories := [2]string{
filepath.Join(gitPath, "objects"),
filepath.Join(gitPath, "refs"),
}
// For the directories we search, if the git repo has been used, there will
// be some file. We don't just search the base git repository because of the
// hook samples that are normally generated with `git init`
isEmpty := true
for _, dir := range directories {
err := fs.Walk(dir, func(path string, info os.FileInfo, err error) error {
// If we find a file, the git directory is "not empty"
// We're looking for object blobs, and ref files
if info != nil && !info.IsDir() {
isEmpty = false
return filepath.SkipDir
}
return err
})
if err != nil && err != filepath.SkipDir {
// There is a .git, but we've encountered an error
return true, err
}
if !isEmpty {
return true, nil
}
}
// Since we know there's a .git directory, but there is nothing in it, we
// throw an error
return true, errors.NewEmptyGitRepositoryError(dir)
}
// GuessEntrypoint tries to guess the valid entrypoint from the source code
// repository. The valid entrypoints are defined above (run,start,exec,execute)
func GuessEntrypoint(fs util.FileSystem, sourceDir string) (string, error) {
files, err := fs.ReadDir(sourceDir)
if err != nil {
return "", err
}
for _, f := range files {
if f.IsDir() || !f.Mode().IsRegular() {
continue
}
if isValidEntrypoint(fs, filepath.Join(sourceDir, f.Name())) {
glog.V(2).Infof("Found valid ENTRYPOINT: %s", f.Name())
return f.Name(), nil
}
}
return "", errors.New("No valid entrypoint specified")
}
// isValidEntrypoint checks if the given file exists and if it is a regular
// file. Valid ENTRYPOINT must be an executable file, so the executable bit must
// be set.
func isValidEntrypoint(fs util.FileSystem, path string) bool {
stat, err := fs.Stat(path)
if err != nil {
return false
}
found := false
for _, pattern := range validEntrypoints {
if pattern.MatchString(stat.Name()) {
found = true
break
}
}
if !found {
return false
}
mode := stat.Mode()
return mode&0111 != 0
}
// ParseFile will see if the input string is a valid file location, where
// file names have a great deal of flexibility and can even match
// expect git clone spec syntax; it also provides details if the file://
// proto was explicitly specified, if we should use OS copy vs. the git
// binary, and if a frag/ref has a bad format
func ParseFile(fs util.FileSystem, source string) (*FileProtoDetails, *URLMods, error) {
// Checking to see if the user included a "file://" in the call
protoSpecified := false
if strings.HasPrefix(source, "file://") && len(source) > 7 {
protoSpecified = true
}
refSpecified := false
path, ref := "", ""
if strings.LastIndex(source, "#") != -1 {
refSpecified = true
segments := strings.SplitN(source, "#", 2)
path = segments[0]
ref = segments[1]
} else {
path = source
}
// in each valid case, like the prior logic in scm.go did, we'll make the
// paths absolute and prepend file:// to the path which callers should
// switch to
_, err := fs.Stat(strings.TrimPrefix(path, "file://"))
if err == nil {
// Is there even a valid .git repository?
isValidGit, err := isValidGitRepository(fs, path)
hasGit := false
if isValidGit {
hasGit = hasGitBinary()
}
if err != nil || !isValidGit || !hasGit {
details := &FileProtoDetails{
UseCopy: true,
FileExists: true,
BadRef: false,
ProtoSpecified: protoSpecified,
}
mods := &URLMods{
Scheme: "file",
Path: makePathAbsolute(strings.TrimPrefix(path, "file://")),
Ref: ref,
}
return details, mods, err
}
// Check is the #ref is valid
badRef := refSpecified && !gitSSHURLPathRef.MatchString(ref)
details := &FileProtoDetails{
BadRef: badRef,
FileExists: true,
ProtoSpecified: protoSpecified,
// this value doesn't really matter, we should not proceed if the git ref is bad
// but let's fallback to "copy" mode if the ref is invalid.
UseCopy: badRef,
}
mods := &URLMods{
Scheme: "file",
Path: makePathAbsolute(strings.TrimPrefix(path, "file://")),
Ref: ref,
}
return details, mods, nil
}
// File does not exist, return bad
details := &FileProtoDetails{
UseCopy: false,
FileExists: false,
BadRef: false,
ProtoSpecified: protoSpecified,
}
return details, nil, nil
}
