lix/src/libstore/fetchers/fetchers.hh
2020-02-06 14:27:31 +01:00

110 lines
2.8 KiB
C++

#pragma once
#include "types.hh"
#include "hash.hh"
#include "path.hh"
#include "tree-info.hh"
#include <memory>
#include <variant>
#include <nlohmann/json_fwd.hpp>
namespace nix { class Store; }
namespace nix::fetchers {
struct Input;
struct Tree
{
Path actualPath;
StorePath storePath;
TreeInfo info;
};
struct Input : std::enable_shared_from_this<Input>
{
std::optional<Hash> narHash; // FIXME: implement
virtual std::string type() const = 0;
virtual ~Input() { }
virtual bool operator ==(const Input & other) const { return false; }
/* Check whether this is a "direct" input, that is, not
one that goes through a registry. */
virtual bool isDirect() const { return true; }
/* Check whether this is an "immutable" input, that is,
one that contains a commit hash or content hash. */
virtual bool isImmutable() const { return (bool) narHash; }
virtual bool contains(const Input & other) const { return false; }
virtual std::optional<std::string> getRef() const { return {}; }
virtual std::optional<Hash> getRev() const { return {}; }
virtual std::string to_string() const = 0;
typedef std::variant<std::string, int64_t> Attr;
typedef std::map<std::string, Attr> Attrs;
Attrs toAttrs() const;
std::pair<Tree, std::shared_ptr<const Input>> fetchTree(ref<Store> store) const;
virtual std::shared_ptr<const Input> applyOverrides(
std::optional<std::string> ref,
std::optional<Hash> rev) const;
virtual std::optional<Path> getSourcePath() const { return {}; }
virtual void markChangedFile(
std::string_view file,
std::optional<std::string> commitMsg) const
{ assert(false); }
virtual void clone(const Path & destDir) const
{
throw Error("do not know how to clone input '%s'", to_string());
}
private:
virtual std::pair<Tree, std::shared_ptr<const Input>> fetchTreeInternal(ref<Store> store) const = 0;
virtual Attrs toAttrsInternal() const = 0;
};
struct ParsedURL;
struct InputScheme
{
virtual ~InputScheme() { }
virtual std::unique_ptr<Input> inputFromURL(const ParsedURL & url) = 0;
virtual std::unique_ptr<Input> inputFromAttrs(const Input::Attrs & attrs) = 0;
};
std::unique_ptr<Input> inputFromURL(const ParsedURL & url);
std::unique_ptr<Input> inputFromURL(const std::string & url);
std::unique_ptr<Input> inputFromAttrs(const Input::Attrs & attrs);
void registerInputScheme(std::unique_ptr<InputScheme> && fetcher);
Input::Attrs jsonToAttrs(const nlohmann::json & json);
nlohmann::json attrsToJson(const Input::Attrs & attrs);
std::optional<std::string> maybeGetStrAttr(const Input::Attrs & attrs, const std::string & name);
std::string getStrAttr(const Input::Attrs & attrs, const std::string & name);
}