diff options
Diffstat (limited to 'src/libfetchers/github.cc')
| -rw-r--r-- | src/libfetchers/github.cc | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/src/libfetchers/github.cc b/src/libfetchers/github.cc new file mode 100644 index 000000000..3fc95ff51 --- /dev/null +++ b/src/libfetchers/github.cc @@ -0,0 +1,195 @@ +#include "download.hh" +#include "cache.hh" +#include "fetchers.hh" +#include "globals.hh" +#include "store-api.hh" + +#include <nlohmann/json.hpp> + +namespace nix::fetchers { + +std::regex ownerRegex("[a-zA-Z][a-zA-Z0-9_-]*", std::regex::ECMAScript); +std::regex repoRegex("[a-zA-Z][a-zA-Z0-9_-]*", std::regex::ECMAScript); + +struct GitHubInput : Input +{ + std::string owner; + std::string repo; + std::optional<std::string> ref; + std::optional<Hash> rev; + + std::string type() const override { return "github"; } + + bool operator ==(const Input & other) const override + { + auto other2 = dynamic_cast<const GitHubInput *>(&other); + return + other2 + && owner == other2->owner + && repo == other2->repo + && 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; } + + ParsedURL toURL() const override + { + auto path = owner + "/" + repo; + assert(!(ref && rev)); + if (ref) path += "/" + *ref; + if (rev) path += "/" + rev->to_string(Base16, false); + return ParsedURL { + .scheme = "github", + .path = path, + }; + } + + Attrs toAttrsInternal() const override + { + Attrs attrs; + attrs.emplace("owner", owner); + attrs.emplace("repo", repo); + if (ref) + attrs.emplace("ref", *ref); + if (rev) + attrs.emplace("rev", rev->gitRev()); + return attrs; + } + + std::pair<Tree, std::shared_ptr<const Input>> fetchTreeInternal(nix::ref<Store> store) const override + { + auto rev = this->rev; + auto ref = this->ref.value_or("master"); + + if (!rev) { + auto url = fmt("https://api.github.com/repos/%s/%s/commits/%s", + owner, repo, ref); + auto json = nlohmann::json::parse( + readFile( + store->toRealPath( + downloadFile(store, url, "source", false).storePath))); + rev = Hash(json["sha"], htSHA1); + debug("HEAD revision for '%s' is %s", url, rev->gitRev()); + } + + auto input = std::make_shared<GitHubInput>(*this); + input->ref = {}; + input->rev = *rev; + + Attrs immutableAttrs({ + {"type", "git-tarball"}, + {"rev", rev->gitRev()}, + }); + + if (auto res = getCache()->lookup(store, immutableAttrs)) { + return { + Tree{ + .actualPath = store->toRealPath(res->second), + .storePath = std::move(res->second), + .info = TreeInfo { + .lastModified = getIntAttr(res->first, "lastModified"), + }, + }, + input + }; + } + + // FIXME: use regular /archive URLs instead? api.github.com + // might have stricter rate limits. + + auto url = fmt("https://api.github.com/repos/%s/%s/tarball/%s", + owner, repo, rev->to_string(Base16, false)); + + std::string accessToken = settings.githubAccessToken.get(); + if (accessToken != "") + url += "?access_token=" + accessToken; + + auto tree = downloadTarball(store, url, "source", true); + + getCache()->add( + store, + immutableAttrs, + { + {"rev", rev->gitRev()}, + {"lastModified", *tree.info.lastModified} + }, + tree.storePath, + true); + + return {std::move(tree), input}; + } +}; + +struct GitHubInputScheme : InputScheme +{ + std::unique_ptr<Input> inputFromURL(const ParsedURL & url) override + { + if (url.scheme != "github") return nullptr; + + auto path = tokenizeString<std::vector<std::string>>(url.path, "/"); + auto input = std::make_unique<GitHubInput>(); + + if (path.size() == 2) { + } else if (path.size() == 3) { + if (std::regex_match(path[2], revRegex)) + input->rev = Hash(path[2], htSHA1); + else if (std::regex_match(path[2], refRegex)) + input->ref = path[2]; + else + throw BadURL("in GitHub URL '%s', '%s' is not a commit hash or branch/tag name", url.url, path[2]); + } else + throw BadURL("GitHub URL '%s' is invalid", url.url); + + for (auto &[name, value] : url.query) { + if (name == "rev") { + if (input->rev) + throw BadURL("GitHub URL '%s' contains multiple commit hashes", url.url); + input->rev = Hash(value, htSHA1); + } + else if (name == "ref") { + if (!std::regex_match(value, refRegex)) + throw BadURL("GitHub URL '%s' contains an invalid branch/tag name", url.url); + if (input->ref) + throw BadURL("GitHub URL '%s' contains multiple branch/tag names", url.url); + input->ref = value; + } + } + + if (input->ref && input->rev) + throw BadURL("GitHub URL '%s' contains both a commit hash and a branch/tag name", url.url); + + input->owner = path[0]; + input->repo = path[1]; + + return input; + } + + std::unique_ptr<Input> inputFromAttrs(const Attrs & attrs) override + { + if (maybeGetStrAttr(attrs, "type") != "github") return {}; + + for (auto & [name, value] : attrs) + if (name != "type" && name != "owner" && name != "repo" && name != "ref" && name != "rev") + throw Error("unsupported GitHub input attribute '%s'", name); + + auto input = std::make_unique<GitHubInput>(); + input->owner = getStrAttr(attrs, "owner"); + input->repo = getStrAttr(attrs, "repo"); + input->ref = maybeGetStrAttr(attrs, "ref"); + if (auto rev = maybeGetStrAttr(attrs, "rev")) + input->rev = Hash(*rev, htSHA1); + return input; + } +}; + +static auto r1 = OnStartup([] { registerInputScheme(std::make_unique<GitHubInputScheme>()); }); + +} |