From 2857b1baaf78bbadeec01adfae8a50fc0f2a254f Mon Sep 17 00:00:00 2001 From: Maximilian Bosch Date: Fri, 17 Jul 2020 20:34:57 +0200 Subject: [PATCH] Add explicit `allRefs = true;` argument to `fetchGit` Sometimes it's necessary to fetch a git repository at a revision and it's unknown which ref contains the revision in question. An example would be a Cargo.lock which only provides the URL and the revision when using a git repository as build input. However it's considered a bad practice to perform a full checkout of a repository since this may take a lot of time and can eat up a lot of disk space. This patch makes a full checkout explicit by adding an `allRefs` argument to `builtins.fetchGit` which fetches all refs if explicitly set to true. Closes #2409 --- src/libfetchers/git.cc | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/src/libfetchers/git.cc b/src/libfetchers/git.cc index 1f298c2d6..81c647f89 100644 --- a/src/libfetchers/git.cc +++ b/src/libfetchers/git.cc @@ -59,12 +59,13 @@ struct GitInputScheme : InputScheme if (maybeGetStrAttr(attrs, "type") != "git") return {}; for (auto & [name, value] : attrs) - if (name != "type" && name != "url" && name != "ref" && name != "rev" && name != "shallow" && name != "submodules" && name != "lastModified" && name != "revCount" && name != "narHash") + if (name != "type" && name != "url" && name != "ref" && name != "rev" && name != "shallow" && name != "submodules" && name != "lastModified" && name != "revCount" && name != "narHash" && name != "allRefs") throw Error("unsupported Git input attribute '%s'", name); parseURL(getStrAttr(attrs, "url")); maybeGetBoolAttr(attrs, "shallow"); maybeGetBoolAttr(attrs, "submodules"); + maybeGetBoolAttr(attrs, "allRefs"); if (auto ref = maybeGetStrAttr(attrs, "ref")) { if (std::regex_search(*ref, badGitRefRegex)) @@ -169,10 +170,12 @@ struct GitInputScheme : InputScheme bool shallow = maybeGetBoolAttr(input.attrs, "shallow").value_or(false); bool submodules = maybeGetBoolAttr(input.attrs, "submodules").value_or(false); + bool allRefs = maybeGetBoolAttr(input.attrs, "allRefs").value_or(false); std::string cacheType = "git"; if (shallow) cacheType += "-shallow"; if (submodules) cacheType += "-submodules"; + if (allRefs) cacheType += "-all-refs"; auto getImmutableAttrs = [&]() { @@ -338,11 +341,15 @@ struct GitInputScheme : InputScheme } } } else { - /* If the local ref is older than ‘tarball-ttl’ seconds, do a - git fetch to update the local ref to the remote ref. */ - struct stat st; - doFetch = stat(localRefFile.c_str(), &st) != 0 || - (uint64_t) st.st_mtime + settings.tarballTtl <= (uint64_t) now; + if (allRefs) { + doFetch = true; + } else { + /* If the local ref is older than ‘tarball-ttl’ seconds, do a + git fetch to update the local ref to the remote ref. */ + struct stat st; + doFetch = stat(localRefFile.c_str(), &st) != 0 || + (uint64_t) st.st_mtime + settings.tarballTtl <= (uint64_t) now; + } } if (doFetch) { @@ -352,9 +359,11 @@ struct GitInputScheme : InputScheme // we're using --quiet for now. Should process its stderr. try { auto ref = input.getRef(); - auto fetchRef = ref->compare(0, 5, "refs/") == 0 - ? *ref - : "refs/heads/" + *ref; + auto fetchRef = allRefs + ? "refs/*" + : ref->compare(0, 5, "refs/") == 0 + ? *ref + : "refs/heads/" + *ref; runProgram("git", true, { "-C", repoDir, "fetch", "--quiet", "--force", "--", actualUrl, fmt("%s:%s", fetchRef, fetchRef) }); } catch (Error & e) { if (!pathExists(localRefFile)) throw;