lix/src/libexpr/flake/flake.hh
Eelco Dolstra aeb7148afd
Some effort to minimize flake dependencies
For example, if the top-level flake depends on
"nixpkgs/release-19.03", and one of its dependencies depends on
"nixpkgs", then the latter will be mapped to "nixpkgs/release-19.03",
rather than whatever the default branch of "nixpkgs" is. Thus you get
only one "nixpkgs" dependency rather than two.

This currently only works in a breadth-first way, so the other way
around (i.e. if the top-level flake depends on "nixpkgs", and a
dependency depends on "nixpkgs/release-19.03") still results in two
"nixpkgs" dependencies.
2019-09-18 23:59:45 +02:00

115 lines
2.8 KiB
C++

#pragma once
#include "types.hh"
#include "flakeref.hh"
#include "lockfile.hh"
namespace nix {
struct Value;
class EvalState;
namespace flake {
static const size_t FLAG_REGISTRY = 0;
static const size_t USER_REGISTRY = 1;
static const size_t GLOBAL_REGISTRY = 2;
struct FlakeRegistry
{
std::map<FlakeRef, FlakeRef> entries;
};
typedef std::vector<std::shared_ptr<FlakeRegistry>> Registries;
std::shared_ptr<FlakeRegistry> readRegistry(const Path &);
void writeRegistry(const FlakeRegistry &, const Path &);
Path getUserRegistryPath();
enum HandleLockFile : unsigned int
{ AllPure // Everything is handled 100% purely
, TopRefUsesRegistries // The top FlakeRef uses the registries, apart from that, everything happens 100% purely
, UpdateLockFile // Update the existing lockfile and write it to file
, UseUpdatedLockFile // `UpdateLockFile` without writing to file
, RecreateLockFile // Recreate the lockfile from scratch and write it to file
, UseNewLockFile // `RecreateLockFile` without writing to file
};
struct SourceInfo
{
// Immutable flakeref that this source tree was obtained from.
FlakeRef resolvedRef;
Path storePath;
// Number of ancestors of the most recent commit.
std::optional<uint64_t> revCount;
// NAR hash of the store path.
Hash narHash;
// A stable timestamp of this source tree. For Git and GitHub
// flakes, the commit date (not author date!) of the most recent
// commit.
std::optional<time_t> lastModified;
SourceInfo(const FlakeRef & resolvRef) : resolvedRef(resolvRef) {};
};
struct FlakeInput
{
FlakeRef ref;
bool isFlake = true;
FlakeInput(const FlakeRef & ref) : ref(ref) {};
};
struct Flake
{
FlakeRef originalRef;
std::string description;
SourceInfo sourceInfo;
std::map<FlakeId, FlakeInput> inputs;
Value * vOutputs; // FIXME: gc
unsigned int edition;
Flake(const FlakeRef & origRef, const SourceInfo & sourceInfo)
: originalRef(origRef), sourceInfo(sourceInfo) {};
};
Flake getFlake(EvalState & state, const FlakeRef & flakeRef, bool allowLookup);
/* Fingerprint of a locked flake; used as a cache key. */
typedef Hash Fingerprint;
struct ResolvedFlake
{
Flake flake;
LockFile lockFile;
ResolvedFlake(Flake && flake, LockFile && lockFile)
: flake(flake), lockFile(lockFile) {}
Fingerprint getFingerprint() const;
};
ResolvedFlake resolveFlake(EvalState &, const FlakeRef &, HandleLockFile);
void callFlake(EvalState & state,
const Flake & flake,
const LockedInputs & inputs,
Value & v);
void callFlake(EvalState & state,
const ResolvedFlake & resFlake,
Value & v);
void updateLockFile(EvalState &, const FlakeRef & flakeRef, bool recreateLockFile);
void gitCloneFlake(FlakeRef flakeRef, EvalState &, Registries, const Path & destDir);
}
}