Convert fetchMercurial to a input type

This enables Mercurial flakes. It also fixes a bug in pure mode where
you could use a branch/tag name rather than a revision.
This commit is contained in:
Eelco Dolstra 2020-01-21 23:49:32 +01:00
parent 9f4d8c6170
commit b33b94748c
3 changed files with 313 additions and 173 deletions

View file

@ -1,175 +1,19 @@
#include "primops.hh" #include "primops.hh"
#include "eval-inline.hh" #include "eval-inline.hh"
#include "download.hh"
#include "store-api.hh" #include "store-api.hh"
#include "pathlocks.hh" #include "fetchers/fetchers.hh"
#include "fetchers/parse.hh"
#include <sys/time.h> #include "fetchers/regex.hh"
#include <regex> #include <regex>
#include <nlohmann/json.hpp>
using namespace std::string_literals;
namespace nix { namespace nix {
struct HgInfo
{
Path storePath;
std::string branch;
std::string rev;
uint64_t revCount = 0;
};
std::regex commitHashRegex("^[0-9a-fA-F]{40}$");
HgInfo exportMercurial(ref<Store> store, const std::string & uri,
std::string rev, const std::string & name)
{
if (rev == "" && hasPrefix(uri, "/") && pathExists(uri + "/.hg")) {
bool clean = runProgram("hg", true, { "status", "-R", uri, "--modified", "--added", "--removed" }) == "";
if (!clean) {
/* This is an unclean working tree. So copy all tracked
files. */
if (!settings.allowDirty)
throw Error("Mercurial tree '%s' is unclean", uri);
if (settings.warnDirty)
warn("Mercurial tree '%s' is unclean", uri);
HgInfo hgInfo;
hgInfo.rev = "0000000000000000000000000000000000000000";
hgInfo.branch = chomp(runProgram("hg", true, { "branch", "-R", uri }));
auto files = tokenizeString<std::set<std::string>>(
runProgram("hg", true, { "status", "-R", uri, "--clean", "--modified", "--added", "--no-status", "--print0" }), "\0"s);
PathFilter filter = [&](const Path & p) -> bool {
assert(hasPrefix(p, uri));
std::string file(p, uri.size() + 1);
auto st = lstat(p);
if (S_ISDIR(st.st_mode)) {
auto prefix = file + "/";
auto i = files.lower_bound(prefix);
return i != files.end() && hasPrefix(*i, prefix);
}
return files.count(file);
};
hgInfo.storePath = store->printStorePath(store->addToStore("source", uri, true, htSHA256, filter));
return hgInfo;
}
}
if (rev == "") rev = "default";
Path cacheDir = fmt("%s/nix/hg/%s", getCacheDir(), hashString(htSHA256, uri).to_string(Base32, false));
Path stampFile = fmt("%s/.hg/%s.stamp", cacheDir, hashString(htSHA512, rev).to_string(Base32, false));
/* If we haven't pulled this repo less than tarball-ttl seconds,
do so now. */
time_t now = time(0);
struct stat st;
if (stat(stampFile.c_str(), &st) != 0 ||
(uint64_t) st.st_mtime + settings.tarballTtl <= (uint64_t) now)
{
/* Except that if this is a commit hash that we already have,
we don't have to pull again. */
if (!(std::regex_match(rev, commitHashRegex)
&& pathExists(cacheDir)
&& runProgram(
RunOptions("hg", { "log", "-R", cacheDir, "-r", rev, "--template", "1" })
.killStderr(true)).second == "1"))
{
Activity act(*logger, lvlTalkative, actUnknown, fmt("fetching Mercurial repository '%s'", uri));
if (pathExists(cacheDir)) {
try {
runProgram("hg", true, { "pull", "-R", cacheDir, "--", uri });
}
catch (ExecError & e) {
string transJournal = cacheDir + "/.hg/store/journal";
/* hg throws "abandoned transaction" error only if this file exists */
if (pathExists(transJournal)) {
runProgram("hg", true, { "recover", "-R", cacheDir });
runProgram("hg", true, { "pull", "-R", cacheDir, "--", uri });
} else {
throw ExecError(e.status, fmt("'hg pull' %s", statusToString(e.status)));
}
}
} else {
createDirs(dirOf(cacheDir));
runProgram("hg", true, { "clone", "--noupdate", "--", uri, cacheDir });
}
}
writeFile(stampFile, "");
}
auto tokens = tokenizeString<std::vector<std::string>>(
runProgram("hg", true, { "log", "-R", cacheDir, "-r", rev, "--template", "{node} {rev} {branch}" }));
assert(tokens.size() == 3);
HgInfo hgInfo;
hgInfo.rev = tokens[0];
hgInfo.revCount = std::stoull(tokens[1]);
hgInfo.branch = tokens[2];
std::string storeLinkName = hashString(htSHA512, name + std::string("\0"s) + hgInfo.rev).to_string(Base32, false);
Path storeLink = fmt("%s/.hg/%s.link", cacheDir, storeLinkName);
try {
auto json = nlohmann::json::parse(readFile(storeLink));
assert(json["name"] == name && json["rev"] == hgInfo.rev);
hgInfo.storePath = json["storePath"];
if (store->isValidPath(store->parseStorePath(hgInfo.storePath))) {
printTalkative("using cached Mercurial store path '%s'", hgInfo.storePath);
return hgInfo;
}
} catch (SysError & e) {
if (e.errNo != ENOENT) throw;
}
Path tmpDir = createTempDir();
AutoDelete delTmpDir(tmpDir, true);
runProgram("hg", true, { "archive", "-R", cacheDir, "-r", rev, tmpDir });
deletePath(tmpDir + "/.hg_archival.txt");
hgInfo.storePath = store->printStorePath(store->addToStore(name, tmpDir));
nlohmann::json json;
json["storePath"] = hgInfo.storePath;
json["uri"] = uri;
json["name"] = name;
json["branch"] = hgInfo.branch;
json["rev"] = hgInfo.rev;
json["revCount"] = hgInfo.revCount;
writeFile(storeLink, json.dump());
return hgInfo;
}
static void prim_fetchMercurial(EvalState & state, const Pos & pos, Value * * args, Value & v) static void prim_fetchMercurial(EvalState & state, const Pos & pos, Value * * args, Value & v)
{ {
std::string url; std::string url;
std::string rev; std::optional<Hash> rev;
std::optional<std::string> ref;
std::string name = "source"; std::string name = "source";
PathSet context; PathSet context;
@ -183,8 +27,15 @@ static void prim_fetchMercurial(EvalState & state, const Pos & pos, Value * * ar
string n(attr.name); string n(attr.name);
if (n == "url") if (n == "url")
url = state.coerceToString(*attr.pos, *attr.value, context, false, false); url = state.coerceToString(*attr.pos, *attr.value, context, false, false);
else if (n == "rev") else if (n == "rev") {
rev = state.forceStringNoCtx(*attr.value, *attr.pos); // Ugly: unlike fetchGit, here the "rev" attribute can
// be both a revision or a branch/tag name.
auto value = state.forceStringNoCtx(*attr.value, *attr.pos);
if (std::regex_match(value, fetchers::revRegex))
rev = Hash(value, htSHA1);
else
ref = value;
}
else if (n == "name") else if (n == "name")
name = state.forceStringNoCtx(*attr.value, *attr.pos); name = state.forceStringNoCtx(*attr.value, *attr.pos);
else else
@ -201,21 +52,36 @@ static void prim_fetchMercurial(EvalState & state, const Pos & pos, Value * * ar
// whitelist. Ah well. // whitelist. Ah well.
state.checkURI(url); state.checkURI(url);
if (evalSettings.pureEval && rev == "") if (evalSettings.pureEval && !rev)
throw Error("in pure evaluation mode, 'fetchMercurial' requires a Mercurial revision"); throw Error("in pure evaluation mode, 'fetchMercurial' requires a Mercurial revision");
auto hgInfo = exportMercurial(state.store, url, rev, name); auto parsedUrl = fetchers::parseURL(
url.find("://") != std::string::npos
? "hg+" + url
: "hg+file://" + url);
if (rev) parsedUrl.query.insert_or_assign("rev", rev->gitRev());
if (ref) parsedUrl.query.insert_or_assign("ref", *ref);
// FIXME: use name
auto input = inputFromURL(parsedUrl);
auto [tree, input2] = input->fetchTree(state.store);
state.mkAttrs(v, 8); state.mkAttrs(v, 8);
mkString(*state.allocAttr(v, state.sOutPath), hgInfo.storePath, PathSet({hgInfo.storePath})); auto storePath = state.store->printStorePath(tree.storePath);
mkString(*state.allocAttr(v, state.symbols.create("branch")), hgInfo.branch); mkString(*state.allocAttr(v, state.sOutPath), storePath, PathSet({storePath}));
mkString(*state.allocAttr(v, state.symbols.create("rev")), hgInfo.rev); if (input2->getRef())
mkString(*state.allocAttr(v, state.symbols.create("shortRev")), std::string(hgInfo.rev, 0, 12)); mkString(*state.allocAttr(v, state.symbols.create("branch")), *input2->getRef());
mkInt(*state.allocAttr(v, state.symbols.create("revCount")), hgInfo.revCount); // Backward compatibility: set 'rev' to
// 0000000000000000000000000000000000000000 for a dirty tree.
auto rev2 = tree.rev.value_or(Hash(htSHA1));
mkString(*state.allocAttr(v, state.symbols.create("rev")), rev2.gitRev());
mkString(*state.allocAttr(v, state.symbols.create("shortRev")), std::string(rev2.gitRev(), 0, 12));
if (tree.revCount)
mkInt(*state.allocAttr(v, state.symbols.create("revCount")), *tree.revCount);
v.attrs->sort(); v.attrs->sort();
if (state.allowedPaths) if (state.allowedPaths)
state.allowedPaths->insert(state.store->toRealPath(hgInfo.storePath)); state.allowedPaths->insert(tree.actualPath);
} }
static RegisterPrimOp r("fetchMercurial", 1, prim_fetchMercurial); static RegisterPrimOp r("fetchMercurial", 1, prim_fetchMercurial);

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@ -0,0 +1,274 @@
#include "fetchers.hh"
#include "parse.hh"
#include "globals.hh"
#include "tarfile.hh"
#include "store-api.hh"
#include "regex.hh"
#include <sys/time.h>
#include <nlohmann/json.hpp>
using namespace std::string_literals;
namespace nix::fetchers {
struct MercurialInput : Input
{
ParsedURL url;
std::optional<std::string> ref;
std::optional<Hash> rev;
MercurialInput(const ParsedURL & url) : url(url)
{
type = "hg";
}
bool operator ==(const Input & other) const override
{
auto other2 = dynamic_cast<const MercurialInput *>(&other);
return
other2
&& url.url == other2->url.url
&& rev == other2->rev
&& ref == other2->ref;
}
bool isImmutable() const override
{
return (bool) rev;
}
std::optional<std::string> getRef() const override { return ref; }
std::optional<Hash> getRev() const override { return rev; }
std::string to_string() const override
{
ParsedURL url2(url);
if (rev) url2.query.insert_or_assign("rev", rev->gitRev());
if (ref) url2.query.insert_or_assign("ref", *ref);
return url2.to_string();
}
std::shared_ptr<const Input> applyOverrides(
std::optional<std::string> ref,
std::optional<Hash> rev) const override
{
if (!ref && !rev) return shared_from_this();
auto res = std::make_shared<MercurialInput>(*this);
if (ref) res->ref = ref;
if (rev) res->rev = rev;
return res;
}
std::optional<Path> getSourcePath() const
{
if (url.scheme == "hg+file" && !ref && !rev)
return url.path;
return {};
}
std::pair<bool, std::string> getActualUrl() const
{
bool isLocal = url.scheme == "hg+file";
return {isLocal, isLocal ? url.path : std::string(url.base, 3)};
}
std::pair<Tree, std::shared_ptr<const Input>> fetchTreeInternal(nix::ref<Store> store) const override
{
auto name = "source";
auto input = std::make_shared<MercurialInput>(*this);
auto [isLocal, actualUrl] = getActualUrl();
// FIXME: return lastModified.
if (!input->ref && !input->rev && isLocal && pathExists(actualUrl + "/.hg")) {
bool clean = runProgram("hg", true, { "status", "-R", actualUrl, "--modified", "--added", "--removed" }) == "";
if (!clean) {
/* This is an unclean working tree. So copy all tracked
files. */
if (!settings.allowDirty)
throw Error("Mercurial tree '%s' is unclean", actualUrl);
if (settings.warnDirty)
warn("Mercurial tree '%s' is unclean", actualUrl);
input->ref = chomp(runProgram("hg", true, { "branch", "-R", actualUrl }));
auto files = tokenizeString<std::set<std::string>>(
runProgram("hg", true, { "status", "-R", actualUrl, "--clean", "--modified", "--added", "--no-status", "--print0" }), "\0"s);
PathFilter filter = [&](const Path & p) -> bool {
assert(hasPrefix(p, actualUrl));
std::string file(p, actualUrl.size() + 1);
auto st = lstat(p);
if (S_ISDIR(st.st_mode)) {
auto prefix = file + "/";
auto i = files.lower_bound(prefix);
return i != files.end() && hasPrefix(*i, prefix);
}
return files.count(file);
};
auto storePath = store->addToStore("source", actualUrl, true, htSHA256, filter);
return {Tree {
.actualPath = store->printStorePath(storePath),
.storePath = std::move(storePath),
}, input};
}
}
if (!input->ref) input->ref = "default";
Path cacheDir = fmt("%s/nix/hg/%s", getCacheDir(), hashString(htSHA256, actualUrl).to_string(Base32, false));
assert(input->rev || input->ref);
auto revOrRef = input->rev ? input->rev->gitRev() : *input->ref;
Path stampFile = fmt("%s/.hg/%s.stamp", cacheDir, hashString(htSHA512, revOrRef).to_string(Base32, false));
/* If we haven't pulled this repo less than tarball-ttl seconds,
do so now. */
time_t now = time(0);
struct stat st;
if (stat(stampFile.c_str(), &st) != 0 ||
(uint64_t) st.st_mtime + settings.tarballTtl <= (uint64_t) now)
{
/* Except that if this is a commit hash that we already have,
we don't have to pull again. */
if (!(input->rev
&& pathExists(cacheDir)
&& runProgram(
RunOptions("hg", { "log", "-R", cacheDir, "-r", input->rev->gitRev(), "--template", "1" })
.killStderr(true)).second == "1"))
{
Activity act(*logger, lvlTalkative, actUnknown, fmt("fetching Mercurial repository '%s'", actualUrl));
if (pathExists(cacheDir)) {
try {
runProgram("hg", true, { "pull", "-R", cacheDir, "--", actualUrl });
}
catch (ExecError & e) {
string transJournal = cacheDir + "/.hg/store/journal";
/* hg throws "abandoned transaction" error only if this file exists */
if (pathExists(transJournal)) {
runProgram("hg", true, { "recover", "-R", cacheDir });
runProgram("hg", true, { "pull", "-R", cacheDir, "--", actualUrl });
} else {
throw ExecError(e.status, fmt("'hg pull' %s", statusToString(e.status)));
}
}
} else {
createDirs(dirOf(cacheDir));
runProgram("hg", true, { "clone", "--noupdate", "--", actualUrl, cacheDir });
}
}
writeFile(stampFile, "");
}
auto tokens = tokenizeString<std::vector<std::string>>(
runProgram("hg", true, { "log", "-R", cacheDir, "-r", revOrRef, "--template", "{node} {rev} {branch}" }));
assert(tokens.size() == 3);
input->rev = Hash(tokens[0], htSHA1);
auto revCount = std::stoull(tokens[1]);
input->ref = tokens[2];
std::string storeLinkName = hashString(htSHA512, name + std::string("\0"s) + input->rev->gitRev()).to_string(Base32, false);
Path storeLink = fmt("%s/.hg/%s.link", cacheDir, storeLinkName);
try {
auto json = nlohmann::json::parse(readFile(storeLink));
assert(json["name"] == name && json["rev"] == input->rev->gitRev());
auto storePath = store->parseStorePath((std::string) json["storePath"]);
if (store->isValidPath(storePath)) {
printTalkative("using cached Mercurial store path '%s'", store->printStorePath(storePath));
return {Tree {
.actualPath = store->printStorePath(storePath),
.storePath = std::move(storePath),
.rev = input->rev,
.revCount = revCount,
}, input};
}
} catch (SysError & e) {
if (e.errNo != ENOENT) throw;
}
Path tmpDir = createTempDir();
AutoDelete delTmpDir(tmpDir, true);
runProgram("hg", true, { "archive", "-R", cacheDir, "-r", input->rev->gitRev(), tmpDir });
deletePath(tmpDir + "/.hg_archival.txt");
auto storePath = store->addToStore(name, tmpDir);
nlohmann::json json;
json["storePath"] = store->printStorePath(storePath);
json["uri"] = actualUrl;
json["name"] = name;
json["branch"] = *input->ref;
json["rev"] = input->rev->gitRev();
json["revCount"] = revCount;
writeFile(storeLink, json.dump());
return {Tree {
.actualPath = store->printStorePath(storePath),
.storePath = std::move(storePath),
.rev = input->rev,
.revCount = revCount,
}, input};
}
};
struct MercurialInputScheme : InputScheme
{
std::unique_ptr<Input> inputFromURL(const ParsedURL & url) override
{
if (url.scheme != "hg+http" &&
url.scheme != "hg+https" &&
url.scheme != "hg+ssh" &&
url.scheme != "hg+file") return nullptr;
auto input = std::make_unique<MercurialInput>(url);
for (auto &[name, value] : url.query) {
if (name == "rev") {
if (!std::regex_match(value, revRegex))
throw BadURL("Mercurial URL '%s' contains an invalid commit hash", url.url);
input->rev = Hash(value, htSHA1);
}
else if (name == "ref") {
if (!std::regex_match(value, refRegex))
throw BadURL("Mercurial URL '%s' contains an invalid branch/tag name", url.url);
input->ref = value;
}
}
return input;
}
};
static auto r1 = OnStartup([] { registerInputScheme(std::make_unique<MercurialInputScheme>()); });
}

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@ -82,8 +82,8 @@ path2=$(nix eval --impure --raw --expr "(builtins.fetchMercurial $repo).outPath"
[[ $(nix eval --impure --raw --expr "(builtins.fetchMercurial $repo).rev") = 0000000000000000000000000000000000000000 ]] [[ $(nix eval --impure --raw --expr "(builtins.fetchMercurial $repo).rev") = 0000000000000000000000000000000000000000 ]]
# ... unless we're using an explicit rev. # ... unless we're using an explicit ref.
path3=$(nix eval --raw --expr "(builtins.fetchMercurial { url = $repo; rev = \"default\"; }).outPath") path3=$(nix eval --impure --raw --expr "(builtins.fetchMercurial { url = $repo; rev = \"default\"; }).outPath")
[[ $path = $path3 ]] [[ $path = $path3 ]]
# Committing should not affect the store path. # Committing should not affect the store path.