diff options
Diffstat (limited to 'src/rebar_pkg_resource.erl')
| -rw-r--r-- | src/rebar_pkg_resource.erl | 79 |
1 files changed, 55 insertions, 24 deletions
diff --git a/src/rebar_pkg_resource.erl b/src/rebar_pkg_resource.erl index 9b430d2..56e08fc 100644 --- a/src/rebar_pkg_resource.erl +++ b/src/rebar_pkg_resource.erl @@ -26,38 +26,69 @@ needs_update(Dir, {pkg, _Name, Vsn}) -> true end. -download(_Dir, {pkg, Name, Vsn}, State) -> +download(TmpDir, Pkg={pkg, Name, Vsn}, State) -> CDN = rebar_state:get(State, rebar_packages_cdn, ?DEFAULT_CDN), PackageDir = hex_package_dir(CDN, State), - Package = binary_to_list(<<Name/binary, "-", Vsn/binary, ".tar">>), - Path = filename:join(PackageDir, Package), + CachePath = filename:join(PackageDir, Package), Url = string:join([CDN, Package], "/"), + cached_download(TmpDir, CachePath, Pkg, Url, etag(CachePath), State). - case request(Url, etag(Path)) of +cached_download(TmpDir, CachePath, Pkg, Url, ETag, State) -> + case request(Url, ETag) of {ok, cached} -> - {tarball, Path}; - {ok, Binary, EtagHeader} -> - file:write_file(Path, Binary), - Etag = etag(Path), - case EtagHeader =:= Etag of - true -> - {tarball, Path}; - false -> - ?DEBUG("Bad md5sum for ~s of ~s comparing to ~s sent by server", - [Path, Etag, EtagHeader]), - throw(bad_etag) - end; + serve_from_cache(TmpDir, CachePath, Pkg, State); + {ok, Body, NewETag} -> + serve_from_download(TmpDir, CachePath, Pkg, NewETag, Body, State); + error when ETag =/= false -> + ?DEBUG("Download ~s error, using ~s from cache", [Url, CachePath]), + serve_from_cache(TmpDir, CachePath, Pkg, State); error -> - case filelib:is_regular(Path) of - true -> - ?DEBUG("Download ~s error, using ~s since it exists", [Url, Path]), - {tarball, Path}; - false -> - throw(request_failed) - end + throw(request_failed) + end. + +serve_from_cache(TmpDir, CachePath, Pkg, State) -> + {Files, Contents, Version, Meta} = extract(TmpDir, CachePath), + case checksums(Pkg, Files, Contents, Version, Meta, State) of + {Chk, Chk, Chk} -> + ok = erl_tar:extract({binary, Contents}, [{cwd, TmpDir}, compressed]), + {ok, true}; + {_Bin, Chk, Chk} -> + ?PRV_ERROR({failed_extract, CachePath}); + {Chk, _Reg, Chk} -> + ?PRV_ERROR({bad_registry_checksum, CachePath}); + {_Bin, _Reg, _Tar} -> + ?PRV_ERROR({bad_checksum, CachePath}) + end. + +serve_from_download(TmpDir, CachePath, Package, ETag, Binary, State) -> + ?DEBUG("Writing ~p to cache at ~s", [Package, CachePath]), + file:write_file(CachePath, Binary), + case etag(CachePath) of + ETag -> + serve_from_cache(TmpDir, CachePath, Package, State); + FileETag -> + ?DEBUG("Download ETag ~s doesn't match cached ETag ~s", [ETag, FileETag]), + ?PRV_ERROR({bad_download, CachePath}) end. + +extract(TmpDir, CachePath) -> + ec_file:mkdir_p(TmpDir), + {ok, Files} = erl_tar:extract(CachePath, [memory]), + {"contents.tar.gz", Contents} = lists:keyfind("contents.tar.gz", 1, Files), + {"VERSION", Version} = lists:keyfind("VERSION", 1, Files), + {"metadata.config", Meta} = lists:keyfind("metadata.config", 1, Files), + {Files, Contents, Version, Meta}. + +checksums(Pkg, Files, Contents, Version, Meta, State) -> + Blob = <<Version/binary, Meta/binary, Contents/binary>>, + <<X:256/big-unsigned>> = crypto:hash(sha256, Blob), + BinChecksum = list_to_binary(string:to_upper(lists:flatten(io_lib:format("~64.16.0b", [X])))), + RegistryChecksum = rebar_packages:registry_sum(Pkg, State), + {"CHECKSUM", TarChecksum} = lists:keyfind("CHECKSUM", 1, Files), + {BinChecksum, RegistryChecksum, TarChecksum}. + make_vsn(_) -> {error, "Replacing version of type pkg not supported."}. @@ -77,8 +108,8 @@ request(Url, ETag) -> [{relaxed, true}], [{body_format, binary}]) of {ok, {{_Version, 200, _Reason}, Headers, Body}} -> - {"etag", ETag1} = lists:keyfind("etag", 1, Headers), ?DEBUG("Successfully downloaded ~s", [Url]), + {"etag", ETag1} = lists:keyfind("etag", 1, Headers), {ok, Body, string:strip(ETag1, both, $")}; {ok, {{_Version, 304, _Reason}, _Headers, _Body}} -> ?DEBUG("Cached copy of ~s still valid", [Url]), |