lix/src/libstore/fetchers/fetchers.cc
2020-02-02 12:29:53 +01:00

117 lines
3.3 KiB
C++

#include "fetchers.hh"
#include "parse.hh"
#include "store-api.hh"
#include <nlohmann/json.hpp>
namespace nix::fetchers {
std::unique_ptr<std::vector<std::unique_ptr<InputScheme>>> inputSchemes = nullptr;
void registerInputScheme(std::unique_ptr<InputScheme> && inputScheme)
{
if (!inputSchemes) inputSchemes = std::make_unique<std::vector<std::unique_ptr<InputScheme>>>();
inputSchemes->push_back(std::move(inputScheme));
}
std::unique_ptr<Input> inputFromURL(const ParsedURL & url)
{
for (auto & inputScheme : *inputSchemes) {
auto res = inputScheme->inputFromURL(url);
if (res) return res;
}
throw Error("input '%s' is unsupported", url.url);
}
std::unique_ptr<Input> inputFromURL(const std::string & url)
{
return inputFromURL(parseURL(url));
}
std::unique_ptr<Input> inputFromAttrs(const Input::Attrs & attrs)
{
for (auto & inputScheme : *inputSchemes) {
auto res = inputScheme->inputFromAttrs(attrs);
if (res) return res;
}
throw Error("input '%s' is unsupported", attrsToJson(attrs));
}
nlohmann::json attrsToJson(const fetchers::Input::Attrs & attrs)
{
nlohmann::json json;
for (auto & attr : attrs) {
if (auto v = std::get_if<int64_t>(&attr.second)) {
json[attr.first] = *v;
} else if (auto v = std::get_if<std::string>(&attr.second)) {
json[attr.first] = *v;
} else abort();
}
return json;
}
Input::Attrs Input::toAttrs() const
{
auto attrs = toAttrsInternal();
if (narHash)
attrs.emplace("narHash", narHash->to_string(SRI));
attrs.emplace("type", type());
return attrs;
}
std::optional<std::string> maybeGetStrAttr(const Input::Attrs & attrs, const std::string & name)
{
auto i = attrs.find(name);
if (i == attrs.end()) return {};
if (auto v = std::get_if<std::string>(&i->second))
return *v;
throw Error("input attribute '%s' is not a string", name);
}
std::string getStrAttr(const Input::Attrs & attrs, const std::string & name)
{
auto s = maybeGetStrAttr(attrs, name);
if (!s)
throw Error("input attribute '%s' is missing", name);
return *s;
}
std::pair<Tree, std::shared_ptr<const Input>> Input::fetchTree(ref<Store> store) const
{
auto [tree, input] = fetchTreeInternal(store);
if (tree.actualPath == "")
tree.actualPath = store->toRealPath(tree.storePath);
if (!tree.info.narHash)
tree.info.narHash = store->queryPathInfo(tree.storePath)->narHash;
if (input->narHash)
assert(input->narHash == tree.info.narHash);
if (narHash && narHash != input->narHash)
throw Error("NAR hash mismatch in input '%s', expected '%s', got '%s'",
to_string(), narHash->to_string(SRI), input->narHash->to_string(SRI));
return {std::move(tree), input};
}
std::shared_ptr<const Input> Input::applyOverrides(
std::optional<std::string> ref,
std::optional<Hash> rev) const
{
if (ref)
throw Error("don't know how to apply '%s' to '%s'", *ref, to_string());
if (rev)
throw Error("don't know how to apply '%s' to '%s'", rev->to_string(Base16, false), to_string());
return shared_from_this();
}
StorePath TreeInfo::computeStorePath(Store & store) const
{
assert(narHash);
return store.makeFixedOutputPath(true, narHash, "source");
}
}