Allow local package identifiers for PyPI packages (go-gitea#21690)

Backport (go-gitea#21690)

Fixes go-gitea#21683

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

integrations/api_packages_pypi_test.go

@@ -28,7 +28,7 @@ func TestPackagePyPI(t *testing.T) {
 	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2}).(*user_model.User)
 
 	packageName := "test-package"
-	packageVersion := "1.0.1"
+	packageVersion := "1.0.1+r1234"
 	packageAuthor := "KN4CK3R"
 	packageDescription := "Test Description"
 
@@ -163,7 +163,7 @@ func TestPackagePyPI(t *testing.T) {
 		nodes := htmlDoc.doc.Find("a").Nodes
 		assert.Len(t, nodes, 2)
 
-		hrefMatcher := regexp.MustCompile(fmt.Sprintf(`%s/files/%s/%s/test\..+#sha256-%s`, root, packageName, packageVersion, hashSHA256))
+		hrefMatcher := regexp.MustCompile(fmt.Sprintf(`%s/files/%s/%s/test\..+#sha256-%s`, root, regexp.QuoteMeta(packageName), regexp.QuoteMeta(packageVersion), hashSHA256))
 
 		for _, a := range nodes {
 			for _, att := range a.Attr {

routers/api/packages/pypi/pypi.go

@@ -26,8 +26,15 @@ import (
 var normalizer = strings.NewReplacer(".", "-", "_", "-")
 var nameMatcher = regexp.MustCompile(`\A[a-zA-Z0-9\.\-_]+\z`)
 
-// https://www.python.org/dev/peps/pep-0440/#appendix-b-parsing-version-strings-with-regular-expressions
-var versionMatcher = regexp.MustCompile(`^([1-9][0-9]*!)?(0|[1-9][0-9]*)(\.(0|[1-9][0-9]*))*((a|b|rc)(0|[1-9][0-9]*))?(\.post(0|[1-9][0-9]*))?(\.dev(0|[1-9][0-9]*))?$`)
+// https://peps.python.org/pep-0440/#appendix-b-parsing-version-strings-with-regular-expressions
+var versionMatcher = regexp.MustCompile(`\Av?` +
+	`(?:[0-9]+!)?` + // epoch
+	`[0-9]+(?:\.[0-9]+)*` + // release segment
+	`(?:[-_\.]?(?:a|b|c|rc|alpha|beta|pre|preview)[-_\.]?[0-9]*)?` + // pre-release
+	`(?:-[0-9]+|[-_\.]?(?:post|rev|r)[-_\.]?[0-9]*)?` + // post release
+	`(?:[-_\.]?dev[-_\.]?[0-9]*)?` + // dev release
+	`(?:\+[a-z0-9]+(?:[-_\.][a-z0-9]+)*)?` + // local version
+	`\z`)
 
 func apiError(ctx *context.Context, status int, obj interface{}) {
 	helper.LogAndProcessError(ctx, status, obj, func(message string) {