forked from lix-project/lix
498 lines
17 KiB
C++
498 lines
17 KiB
C++
#include "primops.hh"
|
||
#include "eval-inline.hh"
|
||
#include "store-api.hh"
|
||
#include "fetchers.hh"
|
||
#include "filetransfer.hh"
|
||
#include "registry.hh"
|
||
#include "url.hh"
|
||
|
||
#include <ctime>
|
||
#include <iomanip>
|
||
#include <regex>
|
||
|
||
namespace nix {
|
||
|
||
void emitTreeAttrs(
|
||
EvalState & state,
|
||
const fetchers::Tree & tree,
|
||
const fetchers::Input & input,
|
||
Value & v,
|
||
bool emptyRevFallback,
|
||
bool forceDirty)
|
||
{
|
||
assert(input.isLocked());
|
||
|
||
auto attrs = state.buildBindings(8);
|
||
|
||
auto storePath = state.store->printStorePath(tree.storePath);
|
||
|
||
attrs.alloc(state.sOutPath).mkString(storePath, {storePath});
|
||
|
||
// FIXME: support arbitrary input attributes.
|
||
|
||
auto narHash = input.getNarHash();
|
||
assert(narHash);
|
||
attrs.alloc("narHash").mkString(narHash->to_string(SRI, true));
|
||
|
||
if (input.getType() == "git")
|
||
attrs.alloc("submodules").mkBool(
|
||
fetchers::maybeGetBoolAttr(input.attrs, "submodules").value_or(false));
|
||
|
||
if (!forceDirty) {
|
||
|
||
if (auto rev = input.getRev()) {
|
||
attrs.alloc("rev").mkString(rev->gitRev());
|
||
attrs.alloc("shortRev").mkString(rev->gitShortRev());
|
||
} else if (emptyRevFallback) {
|
||
// Backwards compat for `builtins.fetchGit`: dirty repos return an empty sha1 as rev
|
||
auto emptyHash = Hash(htSHA1);
|
||
attrs.alloc("rev").mkString(emptyHash.gitRev());
|
||
attrs.alloc("shortRev").mkString(emptyHash.gitShortRev());
|
||
}
|
||
|
||
if (auto revCount = input.getRevCount())
|
||
attrs.alloc("revCount").mkInt(*revCount);
|
||
else if (emptyRevFallback)
|
||
attrs.alloc("revCount").mkInt(0);
|
||
|
||
}
|
||
|
||
if (auto lastModified = input.getLastModified()) {
|
||
attrs.alloc("lastModified").mkInt(*lastModified);
|
||
attrs.alloc("lastModifiedDate").mkString(
|
||
fmt("%s", std::put_time(std::gmtime(&*lastModified), "%Y%m%d%H%M%S")));
|
||
}
|
||
|
||
v.mkAttrs(attrs);
|
||
}
|
||
|
||
std::string fixURI(std::string uri, EvalState & state, const std::string & defaultScheme = "file")
|
||
{
|
||
state.checkURI(uri);
|
||
if (uri.find("://") == std::string::npos) {
|
||
const auto p = ParsedURL {
|
||
.scheme = defaultScheme,
|
||
.authority = "",
|
||
.path = uri
|
||
};
|
||
return p.to_string();
|
||
} else {
|
||
return uri;
|
||
}
|
||
}
|
||
|
||
std::string fixURIForGit(std::string uri, EvalState & state)
|
||
{
|
||
/* Detects scp-style uris (e.g. git@github.com:NixOS/nix) and fixes
|
||
* them by removing the `:` and assuming a scheme of `ssh://`
|
||
* */
|
||
static std::regex scp_uri("([^/]*)@(.*):(.*)");
|
||
if (uri[0] != '/' && std::regex_match(uri, scp_uri))
|
||
return fixURI(std::regex_replace(uri, scp_uri, "$1@$2/$3"), state, "ssh");
|
||
else
|
||
return fixURI(uri, state);
|
||
}
|
||
|
||
struct FetchTreeParams {
|
||
bool emptyRevFallback = false;
|
||
bool allowNameArgument = false;
|
||
};
|
||
|
||
static void fetchTree(
|
||
EvalState & state,
|
||
const PosIdx pos,
|
||
Value * * args,
|
||
Value & v,
|
||
std::optional<std::string> type,
|
||
const FetchTreeParams & params = FetchTreeParams{}
|
||
) {
|
||
fetchers::Input input;
|
||
PathSet context;
|
||
|
||
state.forceValue(*args[0], pos);
|
||
|
||
if (args[0]->type() == nAttrs) {
|
||
state.forceAttrs(*args[0], pos, "while evaluating the argument passed to builtins.fetchTree");
|
||
|
||
fetchers::Attrs attrs;
|
||
|
||
if (auto aType = args[0]->attrs->get(state.sType)) {
|
||
if (type)
|
||
state.debugThrowLastTrace(EvalError({
|
||
.msg = hintfmt("unexpected attribute 'type'"),
|
||
.errPos = state.positions[pos]
|
||
}));
|
||
type = state.forceStringNoCtx(*aType->value, aType->pos, "while evaluating the `type` attribute passed to builtins.fetchTree");
|
||
} else if (!type)
|
||
state.debugThrowLastTrace(EvalError({
|
||
.msg = hintfmt("attribute 'type' is missing in call to 'fetchTree'"),
|
||
.errPos = state.positions[pos]
|
||
}));
|
||
|
||
attrs.emplace("type", type.value());
|
||
|
||
for (auto & attr : *args[0]->attrs) {
|
||
if (attr.name == state.sType) continue;
|
||
state.forceValue(*attr.value, attr.pos);
|
||
if (attr.value->type() == nPath || attr.value->type() == nString) {
|
||
auto s = state.coerceToString(attr.pos, *attr.value, context, "", false, false).toOwned();
|
||
attrs.emplace(state.symbols[attr.name],
|
||
state.symbols[attr.name] == "url"
|
||
? type == "git"
|
||
? fixURIForGit(s, state)
|
||
: fixURI(s, state)
|
||
: s);
|
||
}
|
||
else if (attr.value->type() == nBool)
|
||
attrs.emplace(state.symbols[attr.name], Explicit<bool>{attr.value->boolean});
|
||
else if (attr.value->type() == nInt)
|
||
attrs.emplace(state.symbols[attr.name], uint64_t(attr.value->integer));
|
||
else
|
||
state.debugThrowLastTrace(TypeError("fetchTree argument '%s' is %s while a string, Boolean or integer is expected",
|
||
state.symbols[attr.name], showType(*attr.value)));
|
||
}
|
||
|
||
if (!params.allowNameArgument)
|
||
if (auto nameIter = attrs.find("name"); nameIter != attrs.end())
|
||
state.debugThrowLastTrace(EvalError({
|
||
.msg = hintfmt("attribute 'name' isn’t supported in call to 'fetchTree'"),
|
||
.errPos = state.positions[pos]
|
||
}));
|
||
|
||
input = fetchers::Input::fromAttrs(std::move(attrs));
|
||
} else {
|
||
auto url = state.coerceToString(pos, *args[0], context,
|
||
"while evaluating the first argument passed to the fetcher",
|
||
false, false).toOwned();
|
||
|
||
if (type == "git") {
|
||
fetchers::Attrs attrs;
|
||
attrs.emplace("type", "git");
|
||
attrs.emplace("url", fixURIForGit(url, state));
|
||
input = fetchers::Input::fromAttrs(std::move(attrs));
|
||
} else {
|
||
input = fetchers::Input::fromURL(fixURI(url, state));
|
||
}
|
||
}
|
||
|
||
if (!evalSettings.pureEval && !input.isDirect())
|
||
input = lookupInRegistries(state.store, input).first;
|
||
|
||
if (evalSettings.pureEval && !input.isLocked())
|
||
state.debugThrowLastTrace(EvalError("in pure evaluation mode, 'fetchTree' requires a locked input, at %s", state.positions[pos]));
|
||
|
||
auto [tree, input2] = input.fetch(state.store);
|
||
|
||
state.allowPath(tree.storePath);
|
||
|
||
emitTreeAttrs(state, tree, input2, v, params.emptyRevFallback, false);
|
||
}
|
||
|
||
static void prim_fetchTree(EvalState & state, const PosIdx pos, Value * * args, Value & v)
|
||
{
|
||
experimentalFeatureSettings.require(Xp::Flakes);
|
||
fetchTree(state, pos, args, v, std::nullopt, FetchTreeParams { .allowNameArgument = false });
|
||
}
|
||
|
||
// FIXME: document
|
||
static RegisterPrimOp primop_fetchTree("fetchTree", 1, prim_fetchTree);
|
||
|
||
static void fetch(EvalState & state, const PosIdx pos, Value * * args, Value & v,
|
||
const std::string & who, bool unpack, std::string name)
|
||
{
|
||
std::optional<std::string> url;
|
||
std::optional<Hash> expectedHash;
|
||
|
||
state.forceValue(*args[0], pos);
|
||
|
||
if (args[0]->type() == nAttrs) {
|
||
|
||
for (auto & attr : *args[0]->attrs) {
|
||
std::string_view n(state.symbols[attr.name]);
|
||
if (n == "url")
|
||
url = state.forceStringNoCtx(*attr.value, attr.pos, "while evaluating the url we should fetch");
|
||
else if (n == "sha256")
|
||
expectedHash = newHashAllowEmpty(state.forceStringNoCtx(*attr.value, attr.pos, "while evaluating the sha256 of the content we should fetch"), htSHA256);
|
||
else if (n == "name")
|
||
name = state.forceStringNoCtx(*attr.value, attr.pos, "while evaluating the name of the content we should fetch");
|
||
else
|
||
state.debugThrowLastTrace(EvalError({
|
||
.msg = hintfmt("unsupported argument '%s' to '%s'", n, who),
|
||
.errPos = state.positions[attr.pos]
|
||
}));
|
||
}
|
||
|
||
if (!url)
|
||
state.debugThrowLastTrace(EvalError({
|
||
.msg = hintfmt("'url' argument required"),
|
||
.errPos = state.positions[pos]
|
||
}));
|
||
} else
|
||
url = state.forceStringNoCtx(*args[0], pos, "while evaluating the url we should fetch");
|
||
|
||
if (who == "fetchTarball")
|
||
url = evalSettings.resolvePseudoUrl(*url);
|
||
|
||
state.checkURI(*url);
|
||
|
||
if (name == "")
|
||
name = baseNameOf(*url);
|
||
|
||
if (evalSettings.pureEval && !expectedHash)
|
||
state.debugThrowLastTrace(EvalError("in pure evaluation mode, '%s' requires a 'sha256' argument", who));
|
||
|
||
// early exit if pinned and already in the store
|
||
if (expectedHash && expectedHash->type == htSHA256) {
|
||
auto expectedPath = state.store->makeFixedOutputPath(
|
||
name,
|
||
FixedOutputInfo {
|
||
.hash = {
|
||
.method = unpack ? FileIngestionMethod::Recursive : FileIngestionMethod::Flat,
|
||
.hash = *expectedHash,
|
||
},
|
||
.references = {}
|
||
});
|
||
|
||
if (state.store->isValidPath(expectedPath)) {
|
||
state.allowAndSetStorePathString(expectedPath, v);
|
||
return;
|
||
}
|
||
}
|
||
|
||
// TODO: fetching may fail, yet the path may be substitutable.
|
||
// https://github.com/NixOS/nix/issues/4313
|
||
auto storePath =
|
||
unpack
|
||
? fetchers::downloadTarball(state.store, *url, name, (bool) expectedHash).first.storePath
|
||
: fetchers::downloadFile(state.store, *url, name, (bool) expectedHash).storePath;
|
||
|
||
if (expectedHash) {
|
||
auto hash = unpack
|
||
? state.store->queryPathInfo(storePath)->narHash
|
||
: hashFile(htSHA256, state.store->toRealPath(storePath));
|
||
if (hash != *expectedHash)
|
||
state.debugThrowLastTrace(EvalError((unsigned int) 102, "hash mismatch in file downloaded from '%s':\n specified: %s\n got: %s",
|
||
*url, expectedHash->to_string(Base32, true), hash.to_string(Base32, true)));
|
||
}
|
||
|
||
state.allowAndSetStorePathString(storePath, v);
|
||
}
|
||
|
||
static void prim_fetchurl(EvalState & state, const PosIdx pos, Value * * args, Value & v)
|
||
{
|
||
fetch(state, pos, args, v, "fetchurl", false, "");
|
||
}
|
||
|
||
static RegisterPrimOp primop_fetchurl({
|
||
.name = "__fetchurl",
|
||
.args = {"url"},
|
||
.doc = R"(
|
||
Download the specified URL and return the path of the downloaded
|
||
file. This function is not available if [restricted evaluation
|
||
mode](../command-ref/conf-file.md) is enabled.
|
||
)",
|
||
.fun = prim_fetchurl,
|
||
});
|
||
|
||
static void prim_fetchTarball(EvalState & state, const PosIdx pos, Value * * args, Value & v)
|
||
{
|
||
fetch(state, pos, args, v, "fetchTarball", true, "source");
|
||
}
|
||
|
||
static RegisterPrimOp primop_fetchTarball({
|
||
.name = "fetchTarball",
|
||
.args = {"args"},
|
||
.doc = R"(
|
||
Download the specified URL, unpack it and return the path of the
|
||
unpacked tree. The file must be a tape archive (`.tar`) compressed
|
||
with `gzip`, `bzip2` or `xz`. The top-level path component of the
|
||
files in the tarball is removed, so it is best if the tarball
|
||
contains a single directory at top level. The typical use of the
|
||
function is to obtain external Nix expression dependencies, such as
|
||
a particular version of Nixpkgs, e.g.
|
||
|
||
```nix
|
||
with import (fetchTarball https://github.com/NixOS/nixpkgs/archive/nixos-14.12.tar.gz) {};
|
||
|
||
stdenv.mkDerivation { … }
|
||
```
|
||
|
||
The fetched tarball is cached for a certain amount of time (1
|
||
hour by default) in `~/.cache/nix/tarballs/`. You can change the
|
||
cache timeout either on the command line with `--tarball-ttl`
|
||
*number-of-seconds* or in the Nix configuration file by adding
|
||
the line `tarball-ttl = ` *number-of-seconds*.
|
||
|
||
Note that when obtaining the hash with `nix-prefetch-url` the
|
||
option `--unpack` is required.
|
||
|
||
This function can also verify the contents against a hash. In that
|
||
case, the function takes a set instead of a URL. The set requires
|
||
the attribute `url` and the attribute `sha256`, e.g.
|
||
|
||
```nix
|
||
with import (fetchTarball {
|
||
url = "https://github.com/NixOS/nixpkgs/archive/nixos-14.12.tar.gz";
|
||
sha256 = "1jppksrfvbk5ypiqdz4cddxdl8z6zyzdb2srq8fcffr327ld5jj2";
|
||
}) {};
|
||
|
||
stdenv.mkDerivation { … }
|
||
```
|
||
|
||
This function is not available if [restricted evaluation
|
||
mode](../command-ref/conf-file.md) is enabled.
|
||
)",
|
||
.fun = prim_fetchTarball,
|
||
});
|
||
|
||
static void prim_fetchGit(EvalState & state, const PosIdx pos, Value * * args, Value & v)
|
||
{
|
||
fetchTree(state, pos, args, v, "git", FetchTreeParams { .emptyRevFallback = true, .allowNameArgument = true });
|
||
}
|
||
|
||
static RegisterPrimOp primop_fetchGit({
|
||
.name = "fetchGit",
|
||
.args = {"args"},
|
||
.doc = R"(
|
||
Fetch a path from git. *args* can be a URL, in which case the HEAD
|
||
of the repo at that URL is fetched. Otherwise, it can be an
|
||
attribute with the following attributes (all except `url` optional):
|
||
|
||
- `url`
|
||
|
||
The URL of the repo.
|
||
|
||
- `name` (default: *basename of the URL*)
|
||
|
||
The name of the directory the repo should be exported to in the store.
|
||
|
||
- `rev` (default: *the tip of `ref`*)
|
||
|
||
The [Git revision] to fetch.
|
||
This is typically a commit hash.
|
||
|
||
[Git revision]: https://git-scm.com/docs/git-rev-parse#_specifying_revisions
|
||
|
||
- `ref` (default: `HEAD`)
|
||
|
||
The [Git reference] under which to look for the requested revision.
|
||
This is often a branch or tag name.
|
||
|
||
[Git reference]: https://git-scm.com/book/en/v2/Git-Internals-Git-References
|
||
|
||
By default, the `ref` value is prefixed with `refs/heads/`.
|
||
As of 2.3.0, Nix will not prefix `refs/heads/` if `ref` starts with `refs/`.
|
||
|
||
- `submodules` (default: `false`)
|
||
|
||
A Boolean parameter that specifies whether submodules should be checked out.
|
||
|
||
- `shallow` (default: `false`)
|
||
|
||
A Boolean parameter that specifies whether fetching a shallow clone is allowed.
|
||
|
||
- `allRefs`
|
||
|
||
Whether to fetch all references of the repository.
|
||
With this argument being true, it's possible to load a `rev` from *any* `ref`
|
||
(by default only `rev`s from the specified `ref` are supported).
|
||
|
||
Here are some examples of how to use `fetchGit`.
|
||
|
||
- To fetch a private repository over SSH:
|
||
|
||
```nix
|
||
builtins.fetchGit {
|
||
url = "git@github.com:my-secret/repository.git";
|
||
ref = "master";
|
||
rev = "adab8b916a45068c044658c4158d81878f9ed1c3";
|
||
}
|
||
```
|
||
|
||
- To fetch an arbitrary reference:
|
||
|
||
```nix
|
||
builtins.fetchGit {
|
||
url = "https://github.com/NixOS/nix.git";
|
||
ref = "refs/heads/0.5-release";
|
||
}
|
||
```
|
||
|
||
- If the revision you're looking for is in the default branch of
|
||
the git repository you don't strictly need to specify the branch
|
||
name in the `ref` attribute.
|
||
|
||
However, if the revision you're looking for is in a future
|
||
branch for the non-default branch you will need to specify the
|
||
the `ref` attribute as well.
|
||
|
||
```nix
|
||
builtins.fetchGit {
|
||
url = "https://github.com/nixos/nix.git";
|
||
rev = "841fcbd04755c7a2865c51c1e2d3b045976b7452";
|
||
ref = "1.11-maintenance";
|
||
}
|
||
```
|
||
|
||
> **Note**
|
||
>
|
||
> It is nice to always specify the branch which a revision
|
||
> belongs to. Without the branch being specified, the fetcher
|
||
> might fail if the default branch changes. Additionally, it can
|
||
> be confusing to try a commit from a non-default branch and see
|
||
> the fetch fail. If the branch is specified the fault is much
|
||
> more obvious.
|
||
|
||
- If the revision you're looking for is in the default branch of
|
||
the git repository you may omit the `ref` attribute.
|
||
|
||
```nix
|
||
builtins.fetchGit {
|
||
url = "https://github.com/nixos/nix.git";
|
||
rev = "841fcbd04755c7a2865c51c1e2d3b045976b7452";
|
||
}
|
||
```
|
||
|
||
- To fetch a specific tag:
|
||
|
||
```nix
|
||
builtins.fetchGit {
|
||
url = "https://github.com/nixos/nix.git";
|
||
ref = "refs/tags/1.9";
|
||
}
|
||
```
|
||
|
||
- To fetch the latest version of a remote branch:
|
||
|
||
```nix
|
||
builtins.fetchGit {
|
||
url = "ssh://git@github.com/nixos/nix.git";
|
||
ref = "master";
|
||
}
|
||
```
|
||
|
||
> **Note**
|
||
>
|
||
> Nix will refetch the branch in accordance with
|
||
> the option `tarball-ttl`.
|
||
|
||
> **Note**
|
||
>
|
||
> This behavior is disabled in *Pure evaluation mode*.
|
||
|
||
- To fetch the content of a checked-out work directory:
|
||
|
||
```nix
|
||
builtins.fetchGit ./work-dir
|
||
```
|
||
|
||
If the URL points to a local directory, and no `ref` or `rev` is
|
||
given, `fetchGit` will use the current content of the checked-out
|
||
files, even if they are not committed or added to Git's index. It will
|
||
only consider files added to the Git repository, as listed by `git ls-files`.
|
||
)",
|
||
.fun = prim_fetchGit,
|
||
});
|
||
|
||
}
|