Add an HTTP binary cache store

Allowing stuff like

  NIX_REMOTE=https://cache.nixos.org nix-store -qR /nix/store/x1p1gl3a4kkz5ci0nfbayjqlqmczp1kq-geeqie-1.1

or

  NIX_REMOTE=https://cache.nixos.org nix-store --export /nix/store/x1p1gl3a4kkz5ci0nfbayjqlqmczp1kq-geeqie-1.1 | nix-store --import
This commit is contained in:
Eelco Dolstra 2016-02-29 18:15:20 +01:00
parent 0402b6398d
commit 201b48de60
7 changed files with 102 additions and 61 deletions

View file

@ -55,7 +55,7 @@ bool parseSearchPathArg(Strings::iterator & i,
Path lookupFileArg(EvalState & state, string s) Path lookupFileArg(EvalState & state, string s)
{ {
if (isUri(s)) if (isUri(s))
return downloadFileCached(state.store, s, true); return makeDownloader()->downloadCached(state.store, s, true);
else if (s.size() > 2 && s.at(0) == '<' && s.at(s.size() - 1) == '>') { else if (s.size() > 2 && s.at(0) == '<' && s.at(s.size() - 1) == '>') {
Path p = s.substr(1, s.size() - 2); Path p = s.substr(1, s.size() - 2);
return state.findFile(p); return state.findFile(p);

View file

@ -613,7 +613,7 @@ void EvalState::addToSearchPath(const string & s, bool warn)
} }
if (isUri(path)) if (isUri(path))
path = downloadFileCached(store, path, true); path = makeDownloader()->downloadCached(store, path, true);
path = absPath(path); path = absPath(path);
if (pathExists(path)) { if (pathExists(path)) {

View file

@ -1703,7 +1703,7 @@ void fetch(EvalState & state, const Pos & pos, Value * * args, Value & v,
} else } else
url = state.forceStringNoCtx(*args[0], pos); url = state.forceStringNoCtx(*args[0], pos);
Path res = downloadFileCached(state.store, url, unpack); Path res = makeDownloader()->downloadCached(state.store, url, unpack);
mkString(v, res, PathSet({res})); mkString(v, res, PathSet({res}));
} }

View file

@ -17,9 +17,9 @@ void builtinFetchurl(const BasicDerivation & drv)
options.verifyTLS = false; options.verifyTLS = false;
/* Show a progress indicator, even though stderr is not a tty. */ /* Show a progress indicator, even though stderr is not a tty. */
options.forceProgress = true; options.showProgress = DownloadOptions::yes;
auto data = downloadFile(url->second, options); auto data = makeDownloader()->download(url->second, options);
auto out = drv.env.find("out"); auto out = drv.env.find("out");
if (out == drv.env.end()) throw Error("attribute url missing"); if (out == drv.env.end()) throw Error("attribute url missing");

View file

@ -18,7 +18,7 @@ double getTime()
return tv.tv_sec + (tv.tv_usec / 1000000.0); return tv.tv_sec + (tv.tv_usec / 1000000.0);
} }
struct Curl struct CurlDownloader : public Downloader
{ {
CURL * curl; CURL * curl;
string data; string data;
@ -30,37 +30,40 @@ struct Curl
double prevProgressTime{0}, startTime{0}; double prevProgressTime{0}, startTime{0};
unsigned int moveBack{1}; unsigned int moveBack{1};
static size_t writeCallback(void * contents, size_t size, size_t nmemb, void * userp) size_t writeCallback(void * contents, size_t size, size_t nmemb)
{ {
Curl & c(* (Curl *) userp);
size_t realSize = size * nmemb; size_t realSize = size * nmemb;
c.data.append((char *) contents, realSize); data.append((char *) contents, realSize);
return realSize; return realSize;
} }
static size_t headerCallback(void * contents, size_t size, size_t nmemb, void * userp) static size_t writeCallbackWrapper(void * contents, size_t size, size_t nmemb, void * userp)
{
return ((CurlDownloader *) userp)->writeCallback(contents, size, nmemb);
}
size_t headerCallback(void * contents, size_t size, size_t nmemb)
{ {
Curl & c(* (Curl *) userp);
size_t realSize = size * nmemb; size_t realSize = size * nmemb;
string line = string((char *) contents, realSize); string line = string((char *) contents, realSize);
printMsg(lvlVomit, format("got header: %1%") % trim(line)); printMsg(lvlVomit, format("got header: %1%") % trim(line));
if (line.compare(0, 5, "HTTP/") == 0) { // new response starts if (line.compare(0, 5, "HTTP/") == 0) { // new response starts
c.etag = ""; etag = "";
auto ss = tokenizeString<vector<string>>(line, " "); auto ss = tokenizeString<vector<string>>(line, " ");
c.status = ss.size() >= 2 ? ss[1] : ""; status = ss.size() >= 2 ? ss[1] : "";
} else { } else {
auto i = line.find(':'); auto i = line.find(':');
if (i != string::npos) { if (i != string::npos) {
string name = trim(string(line, 0, i)); string name = trim(string(line, 0, i));
if (name == "ETag") { // FIXME: case if (name == "ETag") { // FIXME: case
c.etag = trim(string(line, i + 1)); etag = trim(string(line, i + 1));
/* Hack to work around a GitHub bug: it sends /* Hack to work around a GitHub bug: it sends
ETags, but ignores If-None-Match. So if we get ETags, but ignores If-None-Match. So if we get
the expected ETag on a 200 response, then shut the expected ETag on a 200 response, then shut
down the connection because we already have the down the connection because we already have the
data. */ data. */
printMsg(lvlDebug, format("got ETag: %1%") % c.etag); printMsg(lvlDebug, format("got ETag: %1%") % etag);
if (c.etag == c.expectedETag && c.status == "200") { if (etag == expectedETag && status == "200") {
printMsg(lvlDebug, format("shutting down on 200 HTTP response with expected ETag")); printMsg(lvlDebug, format("shutting down on 200 HTTP response with expected ETag"));
return 0; return 0;
} }
@ -70,6 +73,11 @@ struct Curl
return realSize; return realSize;
} }
static size_t headerCallbackWrapper(void * contents, size_t size, size_t nmemb, void * userp)
{
return ((CurlDownloader *) userp)->headerCallback(contents, size, nmemb);
}
int progressCallback(double dltotal, double dlnow) int progressCallback(double dltotal, double dlnow)
{ {
if (showProgress) { if (showProgress) {
@ -88,37 +96,20 @@ struct Curl
return _isInterrupted; return _isInterrupted;
} }
static int progressCallback_(void * userp, double dltotal, double dlnow, double ultotal, double ulnow) static int progressCallbackWrapper(void * userp, double dltotal, double dlnow, double ultotal, double ulnow)
{ {
Curl & c(* (Curl *) userp); return ((CurlDownloader *) userp)->progressCallback(dltotal, dlnow);
return c.progressCallback(dltotal, dlnow);
} }
Curl() CurlDownloader()
{ {
requestHeaders = 0; requestHeaders = 0;
curl = curl_easy_init(); curl = curl_easy_init();
if (!curl) throw Error("unable to initialize curl"); if (!curl) throw nix::Error("unable to initialize curl");
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
curl_easy_setopt(curl, CURLOPT_USERAGENT, ("Nix/" + nixVersion).c_str());
curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writeCallback);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *) &curl);
curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, headerCallback);
curl_easy_setopt(curl, CURLOPT_HEADERDATA, (void *) &curl);
curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, progressCallback_);
curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, (void *) &curl);
curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0);
curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
} }
~Curl() ~CurlDownloader()
{ {
if (curl) curl_easy_cleanup(curl); if (curl) curl_easy_cleanup(curl);
if (requestHeaders) curl_slist_free_all(requestHeaders); if (requestHeaders) curl_slist_free_all(requestHeaders);
@ -126,7 +117,27 @@ struct Curl
bool fetch(const string & url, const DownloadOptions & options) bool fetch(const string & url, const DownloadOptions & options)
{ {
showProgress = options.forceProgress || isatty(STDERR_FILENO); showProgress =
options.showProgress == DownloadOptions::yes ||
(options.showProgress == DownloadOptions::automatic && isatty(STDERR_FILENO));
curl_easy_reset(curl);
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
curl_easy_setopt(curl, CURLOPT_USERAGENT, ("Nix/" + nixVersion).c_str());
curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writeCallbackWrapper);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *) this);
curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, headerCallbackWrapper);
curl_easy_setopt(curl, CURLOPT_HEADERDATA, (void *) this);
curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, progressCallbackWrapper);
curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, (void *) this);
curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0);
curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
curl_easy_setopt(curl, CURLOPT_URL, url.c_str()); curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
@ -151,6 +162,9 @@ struct Curl
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, requestHeaders); curl_easy_setopt(curl, CURLOPT_HTTPHEADER, requestHeaders);
if (options.head)
curl_easy_setopt(curl, CURLOPT_NOBODY, 1);
if (showProgress) { if (showProgress) {
std::cerr << (format("downloading %1%... ") % url); std::cerr << (format("downloading %1%... ") % url);
std::cerr.flush(); std::cerr.flush();
@ -163,34 +177,46 @@ struct Curl
std::cerr << "\n"; std::cerr << "\n";
checkInterrupt(); checkInterrupt();
if (res == CURLE_WRITE_ERROR && etag == options.expectedETag) return false; if (res == CURLE_WRITE_ERROR && etag == options.expectedETag) return false;
if (res != CURLE_OK)
throw DownloadError(format("unable to download %1%: %2% (%3%)")
% url % curl_easy_strerror(res) % res);
long httpStatus = 0; long httpStatus = -1;
curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &httpStatus); if (res == CURLE_HTTP_RETURNED_ERROR)
curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &httpStatus);
if (res != CURLE_OK) {
long httpStatus = 0;
Error err =
httpStatus == 404 ? NotFound :
httpStatus == 403 ? Forbidden : Misc;
throw DownloadError(err, format("unable to download %1%: %2% (%3%)")
% url % curl_easy_strerror(res) % res);
}
if (httpStatus == 304) return false; if (httpStatus == 304) return false;
return true; return true;
} }
DownloadResult download(string url, const DownloadOptions & options) override
{
DownloadResult res;
if (fetch(url, options)) {
res.cached = false;
res.data = data;
} else
res.cached = true;
res.etag = etag;
return res;
}
}; };
DownloadResult downloadFile(string url, const DownloadOptions & options) ref<Downloader> makeDownloader()
{ {
DownloadResult res; return make_ref<CurlDownloader>();
Curl curl;
if (curl.fetch(url, options)) {
res.cached = false;
res.data = curl.data;
} else
res.cached = true;
res.etag = curl.etag;
return res;
} }
Path downloadFileCached(ref<Store> store, const string & url, bool unpack) Path Downloader::downloadCached(ref<Store> store, const string & url, bool unpack)
{ {
Path cacheDir = getEnv("XDG_CACHE_HOME", getEnv("HOME", "") + "/.cache") + "/nix/tarballs"; Path cacheDir = getEnv("XDG_CACHE_HOME", getEnv("HOME", "") + "/.cache") + "/nix/tarballs";
createDirs(cacheDir); createDirs(cacheDir);
@ -234,7 +260,7 @@ Path downloadFileCached(ref<Store> store, const string & url, bool unpack)
try { try {
DownloadOptions options; DownloadOptions options;
options.expectedETag = expectedETag; options.expectedETag = expectedETag;
auto res = downloadFile(url, options); auto res = download(url, options);
if (!res.cached) if (!res.cached)
storePath = store->addTextToStore(name, res.data, PathSet(), false); storePath = store->addTextToStore(name, res.data, PathSet(), false);

View file

@ -10,7 +10,8 @@ struct DownloadOptions
{ {
string expectedETag; string expectedETag;
bool verifyTLS{true}; bool verifyTLS{true};
bool forceProgress{false}; enum { yes, no, automatic } showProgress{yes};
bool head{false};
}; };
struct DownloadResult struct DownloadResult
@ -21,11 +22,25 @@ struct DownloadResult
class Store; class Store;
DownloadResult downloadFile(string url, const DownloadOptions & options); struct Downloader
{
virtual DownloadResult download(string url, const DownloadOptions & options) = 0;
Path downloadFileCached(ref<Store> store, const string & url, bool unpack); Path downloadCached(ref<Store> store, const string & url, bool unpack);
MakeError(DownloadError, Error) enum Error { NotFound, Forbidden, Misc };
};
ref<Downloader> makeDownloader();
class DownloadError : public Error
{
public:
Downloader::Error error;
DownloadError(Downloader::Error error, const FormatOrString & fs)
: Error(fs), error(error)
{ }
};
bool isUri(const string & s); bool isUri(const string & s);

View file

@ -158,7 +158,7 @@ int main(int argc, char * * argv)
auto actualUri = resolveMirrorUri(state, uri); auto actualUri = resolveMirrorUri(state, uri);
/* Download the file. */ /* Download the file. */
auto result = downloadFile(actualUri, DownloadOptions()); auto result = makeDownloader()->download(actualUri, DownloadOptions());
AutoDelete tmpDir(createTempDir(), true); AutoDelete tmpDir(createTempDir(), true);
Path tmpFile = (Path) tmpDir + "/tmp"; Path tmpFile = (Path) tmpDir + "/tmp";