nix/src/libstore/uds-remote-store.hh

#pragma once
///@file

#include "remote-store.hh"
#include "remote-store-connection.hh"
#include "indirect-root-store.hh"

namespace nix {

struct UDSRemoteStoreConfig : virtual LocalFSStoreConfig, virtual RemoteStoreConfig
{
    // TODO(fzakaria): Delete this constructor once moved over to the factory pattern
    // outlined in https://github.com/NixOS/nix/issues/10766
    using LocalFSStoreConfig::LocalFSStoreConfig;
    using RemoteStoreConfig::RemoteStoreConfig;

    /**
     * @param authority is the socket path.
     */
    UDSRemoteStoreConfig(
        std::string_view scheme,
        std::string_view authority,
        const Params & params);

    const std::string name() override { return "Local Daemon Store"; }

    std::string doc() override;

    /**
     * The path to the unix domain socket.
     *
     * The default is `settings.nixDaemonSocketFile`, but we don't write
     * that below, instead putting in the constructor.
     */
    Path path;

protected:
    static constexpr char const * scheme = "unix";

public:
    static std::set<std::string> uriSchemes()
    { return {scheme}; }
};

class UDSRemoteStore : public virtual UDSRemoteStoreConfig
    , public virtual IndirectRootStore
    , public virtual RemoteStore
{
public:

    /**
     * @deprecated This is the old API to construct the store.
    */
    UDSRemoteStore(const Params & params);

    /**
     * @param authority is the socket path.
     */
    UDSRemoteStore(
        std::string_view scheme,
        std::string_view authority,
        const Params & params);

    std::string getUri() override;

    ref<SourceAccessor> getFSAccessor(bool requireValidPath = true) override
    { return LocalFSStore::getFSAccessor(requireValidPath); }

    void narFromPath(const StorePath & path, Sink & sink) override
    { LocalFSStore::narFromPath(path, sink); }

    /**
     * Implementation of `IndirectRootStore::addIndirectRoot()` which
     * delegates to the remote store.
     *
     * The idea is that the client makes the direct symlink, so it is
     * owned managed by the client's user account, and the server makes
     * the indirect symlink.
     */
    void addIndirectRoot(const Path & path) override;

private:

    struct Connection : RemoteStore::Connection
    {
        AutoCloseFD fd;
        void closeWrite() override;
    };

    ref<RemoteStore::Connection> openConnection() override;
};

}