feat: Git write-back of parameters (#133)

* feat: Initial support for persisting changes in Git

Signed-off-by: jannfis <jann@mistrust.net>

* Fix unit test

Signed-off-by: jannfis <jann@mistrust.net>

* Fix up some stuff

Signed-off-by: jannfis <jann@mistrust.net>

* More tests and fix mocks

Signed-off-by: jannfis <jann@mistrust.net>

* Spellings

* Spellings

* Spellings

* Fix lint

Signed-off-by: jannfis <jann@mistrust.net>

* Disable GPG tests

* Typo

* Exclude ext code from tests

1 files changed, 95 insertions, 0 deletions

diff --git a/ext/git/git.go b/ext/git/git.go
new file mode 100644
index 0000000..64d3587
--- /dev/null
+++ b/ext/git/git.go
@@ -0,0 +1,95 @@
+package git
+
+import (
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// EnsurePrefix idempotently ensures that a base string has a given prefix.
+func ensurePrefix(s, prefix string) string {
+	if !strings.HasPrefix(s, prefix) {
+		s = prefix + s
+	}
+	return s
+}
+
+// removeSuffix idempotently removes a given suffix
+func removeSuffix(s, suffix string) string {
+	if strings.HasSuffix(s, suffix) {
+		return s[0 : len(s)-len(suffix)]
+	}
+	return s
+}
+
+var (
+	commitSHARegex = regexp.MustCompile("^[0-9A-Fa-f]{40}$")
+	sshURLRegex    = regexp.MustCompile("^(ssh://)?([^/:]*?)@[^@]+$")
+	httpsURLRegex  = regexp.MustCompile("^(https://).*")
+)
+
+// IsCommitSHA returns whether or not a string is a 40 character SHA-1
+func IsCommitSHA(sha string) bool {
+	return commitSHARegex.MatchString(sha)
+}
+
+var truncatedCommitSHARegex = regexp.MustCompile("^[0-9A-Fa-f]{7,}$")
+
+// IsTruncatedCommitSHA returns whether or not a string is a truncated  SHA-1
+func IsTruncatedCommitSHA(sha string) bool {
+	return truncatedCommitSHARegex.MatchString(sha)
+}
+
+// SameURL returns whether or not the two repository URLs are equivalent in location
+func SameURL(leftRepo, rightRepo string) bool {
+	normalLeft := NormalizeGitURL(leftRepo)
+	normalRight := NormalizeGitURL(rightRepo)
+	return normalLeft != "" && normalRight != "" && normalLeft == normalRight
+}
+
+// NormalizeGitURL normalizes a git URL for purposes of comparison, as well as preventing redundant
+// local clones (by normalizing various forms of a URL to a consistent location).
+// Prefer using SameURL() over this function when possible. This algorithm may change over time
+// and should not be considered stable from release to release
+func NormalizeGitURL(repo string) string {
+	repo = strings.ToLower(strings.TrimSpace(repo))
+	if yes, _ := IsSSHURL(repo); yes {
+		if !strings.HasPrefix(repo, "ssh://") {
+			// We need to replace the first colon in git@server... style SSH URLs with a slash, otherwise
+			// net/url.Parse will interpret it incorrectly as the port.
+			repo = strings.Replace(repo, ":", "/", 1)
+			repo = ensurePrefix(repo, "ssh://")
+		}
+	}
+	repo = removeSuffix(repo, ".git")
+	repoURL, err := url.Parse(repo)
+	if err != nil {
+		return ""
+	}
+	normalized := repoURL.String()
+	return strings.TrimPrefix(normalized, "ssh://")
+}
+
+// IsSSHURL returns true if supplied URL is SSH URL
+func IsSSHURL(url string) (bool, string) {
+	matches := sshURLRegex.FindStringSubmatch(url)
+	if len(matches) > 2 {
+		return true, matches[2]
+	}
+	return false, ""
+}
+
+// IsHTTPSURL returns true if supplied URL is HTTPS URL
+func IsHTTPSURL(url string) bool {
+	return httpsURLRegex.MatchString(url)
+}
+
+// TestRepo tests if a repo exists and is accessible with the given credentials
+func TestRepo(repo string, creds Creds, insecure bool, enableLfs bool) error {
+	clnt, err := NewClient(repo, creds, insecure, enableLfs)
+	if err != nil {
+		return err
+	}
+	_, err = clnt.LsRemote("HEAD")
+	return err
+}