nix-super/src/libstore/store-api.hh
John Ericson ee97f107e8 Push getFSAccessor unsupported(...) down Store class hierarchy
More progress on issue #5729.

Instead of having it by the default method in `Store` itself, have it be
the implementation in `DummyStore` and `LegacySSHStore`. Then just the
implementations which fail to provide the method pay the "penalty" of
dealing with the icky `unimplemented` function for non-compliance.

Combined with my other recent PRs, this finally makes `Store` have no
`unsupported` calls!
2023-04-13 13:39:44 -04:00

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#pragma once
///@file
#include "nar-info.hh"
#include "realisation.hh"
#include "path.hh"
#include "derived-path.hh"
#include "hash.hh"
#include "content-address.hh"
#include "serialise.hh"
#include "lru-cache.hh"
#include "sync.hh"
#include "globals.hh"
#include "config.hh"
#include "path-info.hh"
#include "repair-flag.hh"
#include <nlohmann/json_fwd.hpp>
#include <atomic>
#include <limits>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <memory>
#include <string>
#include <chrono>
#include <variant>
namespace nix {
/**
* About the class hierarchy of the store implementations:
*
* Each store type `Foo` consists of two classes:
*
* 1. A class `FooConfig : virtual StoreConfig` that contains the configuration
* for the store
*
* It should only contain members of type `const Setting<T>` (or subclasses
* of it) and inherit the constructors of `StoreConfig`
* (`using StoreConfig::StoreConfig`).
*
* 2. A class `Foo : virtual Store, virtual FooConfig` that contains the
* implementation of the store.
*
* This class is expected to have a constructor `Foo(const Params & params)`
* that calls `StoreConfig(params)` (otherwise you're gonna encounter an
* `assertion failure` when trying to instantiate it).
*
* You can then register the new store using:
*
* ```
* cpp static RegisterStoreImplementation<Foo, FooConfig> regStore;
* ```
*/
MakeError(SubstError, Error);
/**
* denotes a permanent build failure
*/
MakeError(BuildError, Error);
MakeError(InvalidPath, Error);
MakeError(Unsupported, Error);
MakeError(SubstituteGone, Error);
MakeError(SubstituterDisabled, Error);
MakeError(BadStorePath, Error);
MakeError(InvalidStoreURI, Error);
struct BasicDerivation;
struct Derivation;
class FSAccessor;
class NarInfoDiskCache;
class Store;
typedef std::map<std::string, StorePath> OutputPathMap;
enum CheckSigsFlag : bool { NoCheckSigs = false, CheckSigs = true };
enum SubstituteFlag : bool { NoSubstitute = false, Substitute = true };
enum AllowInvalidFlag : bool { DisallowInvalid = false, AllowInvalid = true };
/**
* Magic header of exportPath() output (obsolete).
*/
const uint32_t exportMagic = 0x4558494e;
enum BuildMode { bmNormal, bmRepair, bmCheck };
enum TrustedFlag : bool { NotTrusted = false, Trusted = true };
struct BuildResult;
typedef std::map<StorePath, std::optional<ContentAddress>> StorePathCAMap;
struct StoreConfig : public Config
{
using Config::Config;
StoreConfig() = delete;
StringSet getDefaultSystemFeatures();
virtual ~StoreConfig() { }
virtual const std::string name() = 0;
virtual std::string doc()
{
return "";
}
const PathSetting storeDir_{this, false, settings.nixStore,
"store",
R"(
Logical location of the Nix store, usually
`/nix/store`. Note that you can only copy store paths
between stores if they have the same `store` setting.
)"};
const Path storeDir = storeDir_;
const Setting<int> pathInfoCacheSize{this, 65536, "path-info-cache-size",
"Size of the in-memory store path metadata cache."};
const Setting<bool> isTrusted{this, false, "trusted",
R"(
Whether paths from this store can be used as substitutes
even if they are not signed by a key listed in the
[`trusted-public-keys`](@docroot@/command-ref/conf-file.md#conf-trusted-public-keys)
setting.
)"};
Setting<int> priority{this, 0, "priority",
R"(
Priority of this store when used as a substituter. A lower value means a higher priority.
)"};
Setting<bool> wantMassQuery{this, false, "want-mass-query",
R"(
Whether this store (when used as a substituter) can be
queried efficiently for path validity.
)"};
Setting<StringSet> systemFeatures{this, getDefaultSystemFeatures(),
"system-features",
"Optional features that the system this store builds on implements (like \"kvm\")."};
};
class Store : public std::enable_shared_from_this<Store>, public virtual StoreConfig
{
public:
typedef std::map<std::string, std::string> Params;
protected:
struct PathInfoCacheValue {
/**
* Time of cache entry creation or update
*/
std::chrono::time_point<std::chrono::steady_clock> time_point = std::chrono::steady_clock::now();
/**
* Null if missing
*/
std::shared_ptr<const ValidPathInfo> value;
/**
* Whether the value is valid as a cache entry. The path may not
* exist.
*/
bool isKnownNow();
/**
* Past tense, because a path can only be assumed to exists when
* isKnownNow() && didExist()
*/
inline bool didExist() {
return value != nullptr;
}
};
struct State
{
LRUCache<std::string, PathInfoCacheValue> pathInfoCache;
};
Sync<State> state;
std::shared_ptr<NarInfoDiskCache> diskCache;
Store(const Params & params);
public:
/**
* Perform any necessary effectful operation to make the store up and
* running
*/
virtual void init() {};
virtual ~Store() { }
virtual std::string getUri() = 0;
StorePath parseStorePath(std::string_view path) const;
std::optional<StorePath> maybeParseStorePath(std::string_view path) const;
std::string printStorePath(const StorePath & path) const;
/**
* Deprecated
*
* \todo remove
*/
StorePathSet parseStorePathSet(const PathSet & paths) const;
PathSet printStorePathSet(const StorePathSet & path) const;
/**
* Display a set of paths in human-readable form (i.e., between quotes
* and separated by commas).
*/
std::string showPaths(const StorePathSet & paths);
/**
* @return true if path is in the Nix store (but not the Nix
* store itself).
*/
bool isInStore(PathView path) const;
/**
* @return true if path is a store path, i.e. a direct child of the
* Nix store.
*/
bool isStorePath(std::string_view path) const;
/**
* Split a path like /nix/store/<hash>-<name>/<bla> into
* /nix/store/<hash>-<name> and /<bla>.
*/
std::pair<StorePath, Path> toStorePath(PathView path) const;
/**
* Follow symlinks until we end up with a path in the Nix store.
*/
Path followLinksToStore(std::string_view path) const;
/**
* Same as followLinksToStore(), but apply toStorePath() to the
* result.
*/
StorePath followLinksToStorePath(std::string_view path) const;
/**
* Constructs a unique store path name.
*/
StorePath makeStorePath(std::string_view type,
std::string_view hash, std::string_view name) const;
StorePath makeStorePath(std::string_view type,
const Hash & hash, std::string_view name) const;
StorePath makeOutputPath(std::string_view id,
const Hash & hash, std::string_view name) const;
StorePath makeFixedOutputPath(FileIngestionMethod method,
const Hash & hash, std::string_view name,
const StorePathSet & references = {},
bool hasSelfReference = false) const;
StorePath makeTextPath(std::string_view name, const Hash & hash,
const StorePathSet & references = {}) const;
StorePath makeFixedOutputPathFromCA(std::string_view name, ContentAddress ca,
const StorePathSet & references = {},
bool hasSelfReference = false) const;
/**
* Preparatory part of addToStore().
*
* @return the store path to which srcPath is to be copied
* and the cryptographic hash of the contents of srcPath.
*/
std::pair<StorePath, Hash> computeStorePathForPath(std::string_view name,
const Path & srcPath, FileIngestionMethod method = FileIngestionMethod::Recursive,
HashType hashAlgo = htSHA256, PathFilter & filter = defaultPathFilter) const;
/**
* Preparatory part of addTextToStore().
*
* !!! Computation of the path should take the references given to
* addTextToStore() into account, otherwise we have a (relatively
* minor) security hole: a caller can register a source file with
* bogus references. If there are too many references, the path may
* not be garbage collected when it has to be (not really a problem,
* the caller could create a root anyway), or it may be garbage
* collected when it shouldn't be (more serious).
*
* Hashing the references would solve this (bogus references would
* simply yield a different store path, so other users wouldn't be
* affected), but it has some backwards compatibility issues (the
* hashing scheme changes), so I'm not doing that for now.
*/
StorePath computeStorePathForText(
std::string_view name,
std::string_view s,
const StorePathSet & references) const;
/**
* Check whether a path is valid.
*/
bool isValidPath(const StorePath & path);
protected:
virtual bool isValidPathUncached(const StorePath & path);
public:
/**
* If requested, substitute missing paths. This
* implements nix-copy-closure's --use-substitutes
* flag.
*/
void substitutePaths(const StorePathSet & paths);
/**
* Query which of the given paths is valid. Optionally, try to
* substitute missing paths.
*/
virtual StorePathSet queryValidPaths(const StorePathSet & paths,
SubstituteFlag maybeSubstitute = NoSubstitute);
/**
* Query the set of all valid paths. Note that for some store
* backends, the name part of store paths may be replaced by 'x'
* (i.e. you'll get /nix/store/<hash>-x rather than
* /nix/store/<hash>-<name>). Use queryPathInfo() to obtain the
* full store path. FIXME: should return a set of
* std::variant<StorePath, HashPart> to get rid of this hack.
*/
virtual StorePathSet queryAllValidPaths()
{ unsupported("queryAllValidPaths"); }
constexpr static const char * MissingName = "x";
/**
* Query information about a valid path. It is permitted to omit
* the name part of the store path.
*/
ref<const ValidPathInfo> queryPathInfo(const StorePath & path);
/**
* Asynchronous version of queryPathInfo().
*/
void queryPathInfo(const StorePath & path,
Callback<ref<const ValidPathInfo>> callback) noexcept;
/**
* Query the information about a realisation.
*/
std::shared_ptr<const Realisation> queryRealisation(const DrvOutput &);
/**
* Asynchronous version of queryRealisation().
*/
void queryRealisation(const DrvOutput &,
Callback<std::shared_ptr<const Realisation>> callback) noexcept;
/**
* Check whether the given valid path info is sufficiently attested, by
* either being signed by a trusted public key or content-addressed, in
* order to be included in the given store.
*
* These same checks would be performed in addToStore, but this allows an
* earlier failure in the case where dependencies need to be added too, but
* the addToStore wouldn't fail until those dependencies are added. Also,
* we don't really want to add the dependencies listed in a nar info we
* don't trust anyyways.
*/
virtual bool pathInfoIsUntrusted(const ValidPathInfo &)
{
return true;
}
virtual bool realisationIsUntrusted(const Realisation & )
{
return true;
}
protected:
virtual void queryPathInfoUncached(const StorePath & path,
Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept = 0;
virtual void queryRealisationUncached(const DrvOutput &,
Callback<std::shared_ptr<const Realisation>> callback) noexcept = 0;
public:
/**
* Queries the set of incoming FS references for a store path.
* The result is not cleared.
*/
virtual void queryReferrers(const StorePath & path, StorePathSet & referrers)
{ unsupported("queryReferrers"); }
/**
* @return all currently valid derivations that have `path` as an
* output.
*
* (Note that the result of `queryDeriver()` is the derivation that
* was actually used to produce `path`, which may not exist
* anymore.)
*/
virtual StorePathSet queryValidDerivers(const StorePath & path) { return {}; };
/**
* Query the outputs of the derivation denoted by `path`.
*/
virtual StorePathSet queryDerivationOutputs(const StorePath & path);
/**
* Query the mapping outputName => outputPath for the given
* derivation. All outputs are mentioned so ones mising the mapping
* are mapped to `std::nullopt`.
*/
virtual std::map<std::string, std::optional<StorePath>> queryPartialDerivationOutputMap(const StorePath & path);
/**
* Query the mapping outputName=>outputPath for the given derivation.
* Assume every output has a mapping and throw an exception otherwise.
*/
OutputPathMap queryDerivationOutputMap(const StorePath & path);
/**
* Query the full store path given the hash part of a valid store
* path, or empty if the path doesn't exist.
*/
virtual std::optional<StorePath> queryPathFromHashPart(const std::string & hashPart) = 0;
/**
* Query which of the given paths have substitutes.
*/
virtual StorePathSet querySubstitutablePaths(const StorePathSet & paths) { return {}; };
/**
* Query substitute info (i.e. references, derivers and download
* sizes) of a map of paths to their optional ca values. The info of
* the first succeeding substituter for each path will be returned.
* If a path does not have substitute info, it's omitted from the
* resulting infos map.
*/
virtual void querySubstitutablePathInfos(const StorePathCAMap & paths,
SubstitutablePathInfos & infos);
/**
* Import a path into the store.
*/
virtual void addToStore(const ValidPathInfo & info, Source & narSource,
RepairFlag repair = NoRepair, CheckSigsFlag checkSigs = CheckSigs) = 0;
/**
* A list of paths infos along with a source providing the content
* of the associated store path
*/
using PathsSource = std::vector<std::pair<ValidPathInfo, std::unique_ptr<Source>>>;
/**
* Import multiple paths into the store.
*/
virtual void addMultipleToStore(
Source & source,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs);
virtual void addMultipleToStore(
PathsSource & pathsToCopy,
Activity & act,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs);
/**
* Copy the contents of a path to the store and register the
* validity the resulting path.
*
* @return The resulting path is returned.
* @param filter This function can be used to exclude files (see
* libutil/archive.hh).
*/
virtual StorePath addToStore(
std::string_view name,
const Path & srcPath,
FileIngestionMethod method = FileIngestionMethod::Recursive,
HashType hashAlgo = htSHA256,
PathFilter & filter = defaultPathFilter,
RepairFlag repair = NoRepair,
const StorePathSet & references = StorePathSet());
/**
* Copy the contents of a path to the store and register the
* validity the resulting path, using a constant amount of
* memory.
*/
ValidPathInfo addToStoreSlow(std::string_view name, const Path & srcPath,
FileIngestionMethod method = FileIngestionMethod::Recursive, HashType hashAlgo = htSHA256,
std::optional<Hash> expectedCAHash = {});
/**
* Like addToStore(), but the contents of the path are contained
* in `dump`, which is either a NAR serialisation (if recursive ==
* true) or simply the contents of a regular file (if recursive ==
* false).
* `dump` may be drained
*
* \todo remove?
*/
virtual StorePath addToStoreFromDump(Source & dump, std::string_view name,
FileIngestionMethod method = FileIngestionMethod::Recursive, HashType hashAlgo = htSHA256, RepairFlag repair = NoRepair,
const StorePathSet & references = StorePathSet())
{ unsupported("addToStoreFromDump"); }
/**
* Like addToStore, but the contents written to the output path is a
* regular file containing the given string.
*/
virtual StorePath addTextToStore(
std::string_view name,
std::string_view s,
const StorePathSet & references,
RepairFlag repair = NoRepair) = 0;
/**
* Add a mapping indicating that `deriver!outputName` maps to the output path
* `output`.
*
* This is redundant for known-input-addressed and fixed-output derivations
* as this information is already present in the drv file, but necessary for
* floating-ca derivations and their dependencies as there's no way to
* retrieve this information otherwise.
*/
virtual void registerDrvOutput(const Realisation & output)
{ unsupported("registerDrvOutput"); }
virtual void registerDrvOutput(const Realisation & output, CheckSigsFlag checkSigs)
{ return registerDrvOutput(output); }
/**
* Write a NAR dump of a store path.
*/
virtual void narFromPath(const StorePath & path, Sink & sink) = 0;
/**
* For each path, if it's a derivation, build it. Building a
* derivation means ensuring that the output paths are valid. If
* they are already valid, this is a no-op. Otherwise, validity
* can be reached in two ways. First, if the output paths is
* substitutable, then build the path that way. Second, the
* output paths can be created by running the builder, after
* recursively building any sub-derivations. For inputs that are
* not derivations, substitute them.
*/
virtual void buildPaths(
const std::vector<DerivedPath> & paths,
BuildMode buildMode = bmNormal,
std::shared_ptr<Store> evalStore = nullptr);
/**
* Like buildPaths(), but return a vector of \ref BuildResult
* BuildResults corresponding to each element in paths. Note that in
* case of a build/substitution error, this function won't throw an
* exception, but return a BuildResult containing an error message.
*/
virtual std::vector<BuildResult> buildPathsWithResults(
const std::vector<DerivedPath> & paths,
BuildMode buildMode = bmNormal,
std::shared_ptr<Store> evalStore = nullptr);
/**
* Build a single non-materialized derivation (i.e. not from an
* on-disk .drv file).
*
* @param drvPath This is used to deduplicate worker goals so it is
* imperative that is correct. That said, it doesn't literally need
* to be store path that would be calculated from writing this
* derivation to the store: it is OK if it instead is that of a
* Derivation which would resolve to this (by taking the outputs of
* it's input derivations and adding them as input sources) such
* that the build time referenceable-paths are the same.
*
* In the input-addressed case, we usually *do* use an "original"
* unresolved derivations's path, as that is what will be used in the
* buildPaths case. Also, the input-addressed output paths are verified
* only by that contents of that specific unresolved derivation, so it is
* nice to keep that information around so if the original derivation is
* ever obtained later, it can be verified whether the trusted user in fact
* used the proper output path.
*
* In the content-addressed case, we want to always use the resolved
* drv path calculated from the provided derivation. This serves two
* purposes:
*
* - It keeps the operation trustless, by ruling out a maliciously
* invalid drv path corresponding to a non-resolution-equivalent
* derivation.
*
* - For the floating case in particular, it ensures that the derivation
* to output mapping respects the resolution equivalence relation, so
* one cannot choose different resolution-equivalent derivations to
* subvert dependency coherence (i.e. the property that one doesn't end
* up with multiple different versions of dependencies without
* explicitly choosing to allow it).
*/
virtual BuildResult buildDerivation(const StorePath & drvPath, const BasicDerivation & drv,
BuildMode buildMode = bmNormal);
/**
* Ensure that a path is valid. If it is not currently valid, it
* may be made valid by running a substitute (if defined for the
* path).
*/
virtual void ensurePath(const StorePath & path);
/**
* Add a store path as a temporary root of the garbage collector.
* The root disappears as soon as we exit.
*/
virtual void addTempRoot(const StorePath & path)
{ debug("not creating temporary root, store doesn't support GC"); }
/**
* @return a string representing information about the path that
* can be loaded into the database using `nix-store --load-db` or
* `nix-store --register-validity`.
*/
std::string makeValidityRegistration(const StorePathSet & paths,
bool showDerivers, bool showHash);
/**
* Write a JSON representation of store path metadata, such as the
* hash and the references.
*
* @param includeImpureInfo If true, variable elements such as the
* registration time are included.
*
* @param showClosureSize If true, the closure size of each path is
* included.
*/
nlohmann::json pathInfoToJSON(const StorePathSet & storePaths,
bool includeImpureInfo, bool showClosureSize,
Base hashBase = Base32,
AllowInvalidFlag allowInvalid = DisallowInvalid);
/**
* @return the size of the closure of the specified path, that is,
* the sum of the size of the NAR serialisation of each path in the
* closure.
*/
std::pair<uint64_t, uint64_t> getClosureSize(const StorePath & storePath);
/**
* Optimise the disk space usage of the Nix store by hard-linking files
* with the same contents.
*/
virtual void optimiseStore() { };
/**
* Check the integrity of the Nix store.
*
* @return true if errors remain.
*/
virtual bool verifyStore(bool checkContents, RepairFlag repair = NoRepair) { return false; };
/**
* @return An object to access files in the Nix store.
*/
virtual ref<FSAccessor> getFSAccessor() = 0;
/**
* Repair the contents of the given path by redownloading it using
* a substituter (if available).
*/
virtual void repairPath(const StorePath & path)
{ unsupported("repairPath"); }
/**
* Add signatures to the specified store path. The signatures are
* not verified.
*/
virtual void addSignatures(const StorePath & storePath, const StringSet & sigs)
{ unsupported("addSignatures"); }
/* Utility functions. */
/**
* Read a derivation, after ensuring its existence through
* ensurePath().
*/
Derivation derivationFromPath(const StorePath & drvPath);
/**
* Read a derivation (which must already be valid).
*/
Derivation readDerivation(const StorePath & drvPath);
/**
* Read a derivation from a potentially invalid path.
*/
Derivation readInvalidDerivation(const StorePath & drvPath);
/**
* @param [out] out Place in here the set of all store paths in the
* file system closure of `storePath`; that is, all paths than can
* be directly or indirectly reached from it. `out` is not cleared.
*
* @param flipDirection If true, the set of paths that can reach
* `storePath` is returned; that is, the closures under the
* `referrers` relation instead of the `references` relation is
* returned.
*/
virtual void computeFSClosure(const StorePathSet & paths,
StorePathSet & out, bool flipDirection = false,
bool includeOutputs = false, bool includeDerivers = false);
void computeFSClosure(const StorePath & path,
StorePathSet & out, bool flipDirection = false,
bool includeOutputs = false, bool includeDerivers = false);
/**
* Given a set of paths that are to be built, return the set of
* derivations that will be built, and the set of output paths that
* will be substituted.
*/
virtual void queryMissing(const std::vector<DerivedPath> & targets,
StorePathSet & willBuild, StorePathSet & willSubstitute, StorePathSet & unknown,
uint64_t & downloadSize, uint64_t & narSize);
/**
* Sort a set of paths topologically under the references
* relation. If p refers to q, then p precedes q in this list.
*/
StorePaths topoSortPaths(const StorePathSet & paths);
/**
* Export multiple paths in the format expected by nix-store
* --import.
*/
void exportPaths(const StorePathSet & paths, Sink & sink);
void exportPath(const StorePath & path, Sink & sink);
/**
* Import a sequence of NAR dumps created by exportPaths() into the
* Nix store. Optionally, the contents of the NARs are preloaded
* into the specified FS accessor to speed up subsequent access.
*/
StorePaths importPaths(Source & source, CheckSigsFlag checkSigs = CheckSigs);
struct Stats
{
std::atomic<uint64_t> narInfoRead{0};
std::atomic<uint64_t> narInfoReadAverted{0};
std::atomic<uint64_t> narInfoMissing{0};
std::atomic<uint64_t> narInfoWrite{0};
std::atomic<uint64_t> pathInfoCacheSize{0};
std::atomic<uint64_t> narRead{0};
std::atomic<uint64_t> narReadBytes{0};
std::atomic<uint64_t> narReadCompressedBytes{0};
std::atomic<uint64_t> narWrite{0};
std::atomic<uint64_t> narWriteAverted{0};
std::atomic<uint64_t> narWriteBytes{0};
std::atomic<uint64_t> narWriteCompressedBytes{0};
std::atomic<uint64_t> narWriteCompressionTimeMs{0};
};
const Stats & getStats();
/**
* Computes the full closure of of a set of store-paths for e.g.
* derivations that need this information for `exportReferencesGraph`.
*/
StorePathSet exportReferences(const StorePathSet & storePaths, const StorePathSet & inputPaths);
/**
* Given a store path, return the realisation actually used in the realisation of this path:
* - If the path is a content-addressed derivation, try to resolve it
* - Otherwise, find one of its derivers
*/
std::optional<StorePath> getBuildDerivationPath(const StorePath &);
/**
* Hack to allow long-running processes like hydra-queue-runner to
* occasionally flush their path info cache.
*/
void clearPathInfoCache()
{
state.lock()->pathInfoCache.clear();
}
/**
* Establish a connection to the store, for store types that have
* a notion of connection. Otherwise this is a no-op.
*/
virtual void connect() { };
/**
* Get the protocol version of this store or it's connection.
*/
virtual unsigned int getProtocol()
{
return 0;
};
/**
* @return/ whether store trusts *us*.
*
* `std::nullopt` means we do not know.
*
* @note This is the opposite of the StoreConfig::isTrusted
* store setting. That is about whether *we* trust the store.
*/
virtual std::optional<TrustedFlag> isTrustedClient() = 0;
virtual Path toRealPath(const Path & storePath)
{
return storePath;
}
Path toRealPath(const StorePath & storePath)
{
return toRealPath(printStorePath(storePath));
}
/**
* Synchronises the options of the client with those of the daemon
* (a no-op when theres no daemon)
*/
virtual void setOptions() { }
virtual std::optional<std::string> getVersion() { return {}; }
protected:
Stats stats;
/**
* Helper for methods that are not unsupported: this is used for
* default definitions for virtual methods that are meant to be overriden.
*
* \todo Using this should be a last resort. It is better to make
* the method "virtual pure" and/or move it to a subclass.
*/
[[noreturn]] void unsupported(const std::string & op)
{
throw Unsupported("operation '%s' is not supported by store '%s'", op, getUri());
}
};
/**
* Copy a path from one store to another.
*/
void copyStorePath(
Store & srcStore,
Store & dstStore,
const StorePath & storePath,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs);
/**
* Copy store paths from one store to another. The paths may be copied
* in parallel. They are copied in a topologically sorted order (i.e. if
* A is a reference of B, then A is copied before B), but the set of
* store paths is not automatically closed; use copyClosure() for that.
*
* @return a map of what each path was copied to the dstStore as.
*/
std::map<StorePath, StorePath> copyPaths(
Store & srcStore, Store & dstStore,
const RealisedPath::Set &,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs,
SubstituteFlag substitute = NoSubstitute);
std::map<StorePath, StorePath> copyPaths(
Store & srcStore, Store & dstStore,
const StorePathSet & paths,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs,
SubstituteFlag substitute = NoSubstitute);
/**
* Copy the closure of `paths` from `srcStore` to `dstStore`.
*/
void copyClosure(
Store & srcStore, Store & dstStore,
const RealisedPath::Set & paths,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs,
SubstituteFlag substitute = NoSubstitute);
void copyClosure(
Store & srcStore, Store & dstStore,
const StorePathSet & paths,
RepairFlag repair = NoRepair,
CheckSigsFlag checkSigs = CheckSigs,
SubstituteFlag substitute = NoSubstitute);
/**
* Remove the temporary roots file for this process. Any temporary
* root becomes garbage after this point unless it has been registered
* as a (permanent) root.
*/
void removeTempRoots();
/**
* Resolve the derived path completely, failing if any derivation output
* is unknown.
*/
OutputPathMap resolveDerivedPath(Store &, const DerivedPath::Built &, Store * evalStore = nullptr);
/**
* @return a Store object to access the Nix store denoted by
* uri (slight misnomer...).
*
* @param uri Supported values are:
*
* - local: The Nix store in /nix/store and database in
* /nix/var/nix/db, accessed directly.
*
* - daemon: The Nix store accessed via a Unix domain socket
* connection to nix-daemon.
*
* - unix://<path>: The Nix store accessed via a Unix domain socket
* connection to nix-daemon, with the socket located at <path>.
*
* - auto or : Equivalent to local or daemon depending on
* whether the user has write access to the local Nix
* store/database.
*
* - file://<path>: A binary cache stored in <path>.
*
* - https://<path>: A binary cache accessed via HTTP.
*
* - s3://<path>: A writable binary cache stored on Amazon's Simple
* Storage Service.
*
* - ssh://[user@]<host>: A remote Nix store accessed by running
* nix-store --serve via SSH.
*
* You can pass parameters to the store implementation by appending
* ?key=value&key=value&... to the URI.
*/
ref<Store> openStore(const std::string & uri = settings.storeUri.get(),
const Store::Params & extraParams = Store::Params());
/**
* @return the default substituter stores, defined by the
* substituters option and various legacy options.
*/
std::list<ref<Store>> getDefaultSubstituters();
struct StoreFactory
{
std::set<std::string> uriSchemes;
std::function<std::shared_ptr<Store> (const std::string & scheme, const std::string & uri, const Store::Params & params)> create;
std::function<std::shared_ptr<StoreConfig> ()> getConfig;
};
struct Implementations
{
static std::vector<StoreFactory> * registered;
template<typename T, typename TConfig>
static void add()
{
if (!registered) registered = new std::vector<StoreFactory>();
StoreFactory factory{
.uriSchemes = T::uriSchemes(),
.create =
([](const std::string & scheme, const std::string & uri, const Store::Params & params)
-> std::shared_ptr<Store>
{ return std::make_shared<T>(scheme, uri, params); }),
.getConfig =
([]()
-> std::shared_ptr<StoreConfig>
{ return std::make_shared<TConfig>(StringMap({})); })
};
registered->push_back(factory);
}
};
template<typename T, typename TConfig>
struct RegisterStoreImplementation
{
RegisterStoreImplementation()
{
Implementations::add<T, TConfig>();
}
};
/**
* Display a set of paths in human-readable form (i.e., between quotes
* and separated by commas).
*/
std::string showPaths(const PathSet & paths);
std::optional<ValidPathInfo> decodeValidPathInfo(
const Store & store,
std::istream & str,
std::optional<HashResult> hashGiven = std::nullopt);
/**
* Split URI into protocol+hierarchy part and its parameter set.
*/
std::pair<std::string, Store::Params> splitUriAndParams(const std::string & uri);
std::optional<ContentAddress> getDerivationCA(const BasicDerivation & drv);
std::map<DrvOutput, StorePath> drvOutputReferences(
Store & store,
const Derivation & drv,
const StorePath & outputPath);
}