lix/src/libutil/url-name.cc

59 lines
2.1 KiB
C++

#include <regex>
#include "url-name.hh"
namespace nix {
static std::string const attributeNamePattern("[a-zA-Z0-9_-]+");
static std::regex const lastAttributeRegex("(?:" + attributeNamePattern + "\\.)*(?!default)(" + attributeNamePattern +")(\\^.*)?");
static std::string const pathSegmentPattern("[a-zA-Z0-9_-]+");
static std::regex const lastPathSegmentRegex(".*/(" + pathSegmentPattern +")");
static std::regex const secondPathSegmentRegex("(?:" + pathSegmentPattern + ")/(" + pathSegmentPattern +")(?:/.*)?");
static std::regex const gitProviderRegex("github|gitlab|sourcehut");
static std::regex const gitSchemeRegex("git($|\\+.*)");
static std::regex const defaultOutputRegex(".*\\.default($|\\^.*)");
std::optional<std::string> getNameFromURL(ParsedURL const & url)
{
std::smatch match;
/* If there is a dir= argument, use its value */
if (url.query.count("dir") > 0) {
return url.query.at("dir");
}
/* If the fragment isn't a "default" and contains two attribute elements, use the last one */
if (std::regex_match(url.fragment, match, lastAttributeRegex)) {
return match.str(1);
}
/* If this is a github/gitlab/sourcehut flake, use the repo name */
if (
std::regex_match(url.scheme, gitProviderRegex)
&& std::regex_match(url.path, match, secondPathSegmentRegex)
) {
return match.str(1);
}
/* If it is a regular git flake, use the directory name */
if (
std::regex_match(url.scheme, gitSchemeRegex)
&& std::regex_match(url.path, match, lastPathSegmentRegex)
) {
return match.str(1);
}
/* If everything failed but there is a non-default fragment, use it in full */
if (!url.fragment.empty() && !std::regex_match(url.fragment, defaultOutputRegex))
return url.fragment;
/* If there is no fragment, take the last element of the path */
if (std::regex_match(url.path, match, lastPathSegmentRegex))
return match.str(1);
/* If even that didn't work, the URL does not contain enough info to determine a useful name */
return {};
}
}