lix/src/libfetchers/indirect.cc
Eelco Dolstra 85c8be6286 Remove static variable name clashes
This was useful for an experiment with building Nix as a single
compilation unit. It's not very useful otherwise but also doesn't
hurt...
2020-10-06 13:49:20 +02:00

106 lines
3.5 KiB
C++

#include "fetchers.hh"
#include "url-parts.hh"
namespace nix::fetchers {
std::regex flakeRegex("[a-zA-Z][a-zA-Z0-9_-]*", std::regex::ECMAScript);
struct IndirectInputScheme : InputScheme
{
std::optional<Input> inputFromURL(const ParsedURL & url) override
{
if (url.scheme != "flake") return {};
auto path = tokenizeString<std::vector<std::string>>(url.path, "/");
std::optional<Hash> rev;
std::optional<std::string> ref;
if (path.size() == 1) {
} else if (path.size() == 2) {
if (std::regex_match(path[1], revRegex))
rev = Hash::parseAny(path[1], htSHA1);
else if (std::regex_match(path[1], refRegex))
ref = path[1];
else
throw BadURL("in flake URL '%s', '%s' is not a commit hash or branch/tag name", url.url, path[1]);
} else if (path.size() == 3) {
if (!std::regex_match(path[1], refRegex))
throw BadURL("in flake URL '%s', '%s' is not a branch/tag name", url.url, path[1]);
ref = path[1];
if (!std::regex_match(path[2], revRegex))
throw BadURL("in flake URL '%s', '%s' is not a commit hash", url.url, path[2]);
rev = Hash::parseAny(path[2], htSHA1);
} else
throw BadURL("GitHub URL '%s' is invalid", url.url);
std::string id = path[0];
if (!std::regex_match(id, flakeRegex))
throw BadURL("'%s' is not a valid flake ID", id);
// FIXME: forbid query params?
Input input;
input.direct = false;
input.attrs.insert_or_assign("type", "indirect");
input.attrs.insert_or_assign("id", id);
if (rev) input.attrs.insert_or_assign("rev", rev->gitRev());
if (ref) input.attrs.insert_or_assign("ref", *ref);
return input;
}
std::optional<Input> inputFromAttrs(const Attrs & attrs) override
{
if (maybeGetStrAttr(attrs, "type") != "indirect") return {};
for (auto & [name, value] : attrs)
if (name != "type" && name != "id" && name != "ref" && name != "rev" && name != "narHash")
throw Error("unsupported indirect input attribute '%s'", name);
auto id = getStrAttr(attrs, "id");
if (!std::regex_match(id, flakeRegex))
throw BadURL("'%s' is not a valid flake ID", id);
Input input;
input.direct = false;
input.attrs = attrs;
return input;
}
ParsedURL toURL(const Input & input) override
{
ParsedURL url;
url.scheme = "flake";
url.path = getStrAttr(input.attrs, "id");
if (auto ref = input.getRef()) { url.path += '/'; url.path += *ref; };
if (auto rev = input.getRev()) { url.path += '/'; url.path += rev->gitRev(); };
return url;
}
bool hasAllInfo(const Input & input) override
{
return false;
}
Input applyOverrides(
const Input & _input,
std::optional<std::string> ref,
std::optional<Hash> rev) override
{
auto input(_input);
if (rev) input.attrs.insert_or_assign("rev", rev->gitRev());
if (ref) input.attrs.insert_or_assign("ref", *ref);
return input;
}
std::pair<Tree, Input> fetch(ref<Store> store, const Input & input) override
{
throw Error("indirect input '%s' cannot be fetched directly", input.to_string());
}
};
static auto rIndirectInputScheme = OnStartup([] { registerInputScheme(std::make_unique<IndirectInputScheme>()); });
}