Support repo's Appstream data download and install

Repositories can provide Appstream data for the packages they contain.
This Appstream data is consumed by applications like the GNOME Software
or KDE Discover, thus the users can see the packages (apps) in them.

This is to be in pair with PackageKit, which does download and install
the repo's Appstream data.

As this adds a dependency on the `appstream` library, there is also
a CMake option WITH_APPSTREAM to be able to turn the support off.

The support is built by default, but the Appstream data is not downloaded
unless "optional_metadata_types" config option contains "appstream".

Closes #1564

CMakeLists.txt

@@ -34,6 +34,7 @@ option(WITH_COMPS "Build with comps groups and environments support" ON)
 option(WITH_MODULEMD "Build with modulemd modules support" ON)
 option(WITH_ZCHUNK "Build with zchunk delta compression support" ON)
 option(WITH_SYSTEMD "Build with systemd and D-Bus features" ON)
+option(WITH_APPSTREAM "Build with appstream support" ON)
 option(ENABLE_SOLV_URPMREORDER "Build with support for URPM-like solution reordering?" OFF)
 option(ENABLE_SOLV_FOCUSNEW "Build with SOLVER_FLAG_FOCUS_NEW libsolv flag enabled to ensure new dependencies are installed in latests versions?" ON)
 
@@ -129,6 +130,10 @@ if (WITH_MODULEMD)
     add_definitions(-DWITH_MODULEMD)
 endif()
 
+if (WITH_APPSTREAM)
+    add_definitions(-DWITH_APPSTREAM)
+endif()
+
 include_directories("${PROJECT_SOURCE_DIR}/include")
 include_directories("${PROJECT_SOURCE_DIR}/common")
 

dnf5.spec

@@ -71,6 +71,7 @@ Provides:       dnf5-command(versionlock)
 
 # ========== build options ==========
 
+%bcond_without appstream
 %bcond_without dnf5daemon_client
 %bcond_without dnf5daemon_server
 %bcond_without libdnf_cli
@@ -143,6 +144,9 @@ BuildRequires:  bash-completion
 BuildRequires:  cmake
 BuildRequires:  doxygen
 BuildRequires:  gettext
+%if %{with appstream}
+BuildRequires:  pkgconfig(appstream) >= 0.16
+%endif
 BuildRequires:  pkgconfig(check)
 BuildRequires:  pkgconfig(fmt)
 BuildRequires:  pkgconfig(json-c)
@@ -797,6 +801,7 @@ automatically and regularly from systemd timers, cron jobs or similar.
     \
     -DENABLE_SOLV_FOCUSNEW=%{?with_focus_new:ON}%{!?with_focus_new:OFF} \
     \
+    -DWITH_APPSTREAM=%{?with_appstream:ON}%{!?with_appstream:OFF} \
     -DWITH_DNF5DAEMON_CLIENT=%{?with_dnf5daemon_client:ON}%{!?with_dnf5daemon_client:OFF} \
     -DWITH_DNF5DAEMON_SERVER=%{?with_dnf5daemon_server:ON}%{!?with_dnf5daemon_server:OFF} \
     -DWITH_LIBDNF5_CLI=%{?with_libdnf_cli:ON}%{!?with_libdnf_cli:OFF} \

include/libdnf5/conf/const.hpp

@@ -64,9 +64,15 @@ constexpr const char * METADATA_TYPE_OTHER = "other";
 constexpr const char * METADATA_TYPE_PRESTO = "presto";
 constexpr const char * METADATA_TYPE_UPDATEINFO = "updateinfo";
 constexpr const char * METADATA_TYPE_ALL = "all";
+constexpr const char * METADATA_TYPE_APPSTREAM = "appstream";
 
 const std::set<std::string> OPTIONAL_METADATA_TYPES{
-    METADATA_TYPE_COMPS, METADATA_TYPE_FILELISTS, METADATA_TYPE_OTHER, METADATA_TYPE_PRESTO, METADATA_TYPE_UPDATEINFO};
+    METADATA_TYPE_COMPS,
+    METADATA_TYPE_FILELISTS,
+    METADATA_TYPE_OTHER,
+    METADATA_TYPE_PRESTO,
+    METADATA_TYPE_UPDATEINFO,
+    METADATA_TYPE_APPSTREAM};
 
 }  // namespace libdnf5
 

include/libdnf5/repo/repo.hpp

@@ -144,6 +144,10 @@ class LIBDNF_API Repo {
     // @replaces libdnf:repo/Repo.hpp:method:Repo.loadCache(bool throwExcept)
     void read_metadata_cache();
 
+    /// Installs downloaded Appstream data for the repo, if available and
+    /// if built with the Appstream support.
+    void install_appstream();
+
     /// Checks whether the locally downloaded metadata are in sync with the origin.
     /// @return `true` if metadata are in sync with the origin, `false` otherwise.
     bool is_in_sync();

libdnf5/CMakeLists.txt

@@ -81,6 +81,13 @@ if (WITH_MODULEMD)
     target_link_libraries(libdnf5_static PRIVATE ${LIBMODULEMD_LIBRARIES})
 endif()
 
+if (WITH_APPSTREAM)
+    pkg_check_modules(APPSTREAM REQUIRED appstream>=0.16)
+    include_directories(${APPSTREAM_INCLUDE_DIRS})
+    target_link_libraries(libdnf5 PRIVATE ${APPSTREAM_LIBRARIES})
+    target_link_libraries(libdnf5_static PRIVATE ${APPSTREAM_LIBRARIES})
+endif()
+
 if (ENABLE_SOLV_FOCUSNEW)
     pkg_check_modules(LIBSOLV REQUIRED libsolv>=0.7.30)
 else()

libdnf5/repo/repo.cpp

@@ -52,6 +52,9 @@ extern "C" {
 #include <filesystem>
 #include <set>
 
+#ifdef WITH_APPSTREAM
+#include <appstream.h>
+#endif
 
 namespace libdnf5::repo {
 
@@ -203,6 +206,31 @@ void Repo::read_metadata_cache() {
     p_impl->downloader->load_local();
 }
 
+void Repo::install_appstream() {
+#ifdef WITH_APPSTREAM
+    if (!p_impl->config.get_main_config().get_optional_metadata_types_option().get_value().contains(
+            libdnf5::METADATA_TYPE_APPSTREAM))
+        return;
+
+    std::string repo_id = p_impl->config.get_id();
+    auto appstream_metadata = p_impl->downloader->get_appstream_metadata();
+    for (auto & item : appstream_metadata) {
+        const std::string path = item.second;
+        GError * local_error = NULL;
+
+        if (!as_utils_install_metadata_file(
+                AS_METADATA_LOCATION_CACHE, path.c_str(), repo_id.c_str(), NULL, &local_error)) {
+            p_impl->base->get_logger()->debug(
+                "Failed to install Appstream metadata file '{}' for repo '{}': {}",
+                path,
+                repo_id,
+                local_error ? local_error->message : "Unknown error");
+        }
+
+        g_clear_error(&local_error);
+    }
+#endif
+}
 
 bool Repo::is_in_sync() {
     if (!p_impl->config.get_metalink_option().empty() && !p_impl->config.get_metalink_option().get_value().empty()) {
@@ -413,6 +441,13 @@ void Repo::load_available_repo() {
     auto optional_metadata = p_impl->config.get_main_config().get_optional_metadata_types_option().get_value();
     const bool all_metadata = optional_metadata.contains(libdnf5::METADATA_TYPE_ALL);
 
+    if (all_metadata || optional_metadata.contains(libdnf5::METADATA_TYPE_APPSTREAM)) {
+        auto appstream_metadata = p_impl->downloader->get_appstream_metadata();
+        for (auto & item : appstream_metadata) {
+            p_impl->solv_repo->load_repo_ext(RepodataType::APPSTREAM, item.first, *p_impl->downloader.get());
+        }
+    }
+
     if (all_metadata || optional_metadata.contains(libdnf5::METADATA_TYPE_FILELISTS)) {
         p_impl->solv_repo->load_repo_ext(RepodataType::FILELISTS, *p_impl->downloader.get());
     }

libdnf5/repo/repo_downloader.cpp

@@ -389,6 +389,25 @@ const std::string & RepoDownloader::get_metadata_path(const std::string & metada
     return it != metadata_paths.end() ? it->second : empty;
 }
 
+bool RepoDownloader::is_appstream_metadata_type(const std::string & type) const {
+    /* TODO: make the list configurable with this default */
+    return utils::string::starts_with(type, "appstream") || utils::string::starts_with(type, "appdata");
+}
+
+std::vector<std::pair<std::string, std::string>> RepoDownloader::get_appstream_metadata() const {
+    std::vector<std::pair<std::string, std::string>> appstream_metadata;
+    /* The RepoDownloader::common_handle_setup() sets the expected names,
+       check for the starts_with() only here, to avoid copying the list here. */
+
+    for (auto it = metadata_paths.begin(); it != metadata_paths.end(); it++) {
+        const std::string type = it->first;
+        const std::string path = it->second;
+
+        if (is_appstream_metadata_type(type))
+            appstream_metadata.push_back(std::pair<std::string, std::string>(type, path));
+    }
+    return appstream_metadata;
+}
 
 LibrepoHandle RepoDownloader::init_local_handle() {
     LibrepoHandle h;
@@ -503,6 +522,30 @@ void RepoDownloader::common_handle_setup(LibrepoHandle & h) {
         dlist.push_back(nullptr);
         h.set_opt(LRO_YUMDLIST, dlist.data());
     }
+#ifdef WITH_APPSTREAM
+    if (get_optional_metadata().extract(libdnf5::METADATA_TYPE_APPSTREAM)) {
+        // ideally, the repomd.xml file should be read and every type matching is_appstream_metadata_type()
+        // would be added from it, but the content is not known at this point and when it is known, then
+        // it's too late, thus declare some "expected" types to be downloaded here
+        dlist.push_back("appstream");
+        dlist.push_back("appstream-icons");
+        dlist.push_back("appstream-icons-48x48");
+        dlist.push_back("appstream-icons-48x48@2");
+        dlist.push_back("appstream-icons-64x64");
+        dlist.push_back("appstream-icons-64x64@2");
+        dlist.push_back("appstream-icons-128x128");
+        dlist.push_back("appstream-icons-128x128@2");
+        // consult the prefixes with the is_appstream_metadata_type()
+        dlist.push_back("appdata");
+        dlist.push_back("appdata-icons");
+        dlist.push_back("appdata-icons-48x48");
+        dlist.push_back("appdata-icons-48x48@2");
+        dlist.push_back("appdata-icons-64x64");
+        dlist.push_back("appdata-icons-64x64@2");
+        dlist.push_back("appdata-icons-128x128");
+        dlist.push_back("appdata-icons-128x128@2");
+    }
+#endif
 
     h.set_opt(LRO_PRESERVETIME, static_cast<long>(preserve_remote_time));
     h.set_opt(LRO_REPOTYPE, LR_YUMREPO);

libdnf5/repo/repo_downloader.hpp

@@ -56,6 +56,7 @@ class RepoDownloader {
     static constexpr const char * MD_FILENAME_GROUP_GZ = "group_gz";
     static constexpr const char * MD_FILENAME_GROUP = "group";
     static constexpr const char * MD_FILENAME_MODULES = "modules";
+    static constexpr const char * MD_FILENAME_APPSTREAM = "appstream";
 
     RepoDownloader(const libdnf5::BaseWeakPtr & base, const ConfigRepo & config, Repo::Type repo_type);
 
@@ -74,6 +75,7 @@ class RepoDownloader {
     void * get_user_data() const noexcept;
 
     const std::string & get_metadata_path(const std::string & metadata_type) const;
+    std::vector<std::pair<std::string, std::string>> get_appstream_metadata() const;
 
 
 private:
@@ -99,6 +101,7 @@ class RepoDownloader {
     time_t get_system_epoch() const;
 
     std::set<std::string> get_optional_metadata() const;
+    bool is_appstream_metadata_type(const std::string & type) const;
 
     libdnf5::BaseWeakPtr base;
     const ConfigRepo & config;

libdnf5/repo/repo_sack.cpp

@@ -575,6 +575,7 @@ void RepoSack::Impl::update_and_load_repos(libdnf5::repo::RepoQuery & repos, boo
                 RepoCache(base, cache_dir).remove_attribute(RepoCache::ATTRIBUTE_EXPIRED);
                 repo->mark_fresh();
                 repo->read_metadata_cache();
+                repo->install_appstream();
 
                 repos_for_processing.erase(repos_for_processing.begin() + static_cast<ssize_t>(idx));
                 send_to_sack_loader(repo);

libdnf5/repo/solv_repo.cpp

@@ -179,6 +179,9 @@ static const char * repodata_type_to_name(RepodataType type) {
             return RepoDownloader::MD_FILENAME_GROUP;
         case RepodataType::OTHER:
             return RepoDownloader::MD_FILENAME_OTHER;
+        case RepodataType::APPSTREAM:
+            libdnf_throw_assertion("No static filename for RepodataType::APPSTREAM");
+            break;
     }
 
     libdnf_throw_assertion("Unknown RepodataType: {}", utils::to_underlying(type));
@@ -197,6 +200,8 @@ static int repodata_type_to_flags(RepodataType type) {
             return 0;
         case RepodataType::OTHER:
             return REPO_EXTEND_SOLVABLES | REPO_LOCALPOOL;
+        case RepodataType::APPSTREAM:
+            return 0;
     }
 
     libdnf_throw_assertion("Unknown RepodataType: {}", utils::to_underlying(type));
@@ -313,17 +318,22 @@ void SolvRepo::load_system_repo_ext(RepodataType type) {
         case RepodataType::OTHER:
         case RepodataType::PRESTO:
         case RepodataType::UPDATEINFO:
+        case RepodataType::APPSTREAM:
             throw SolvError(M_("Unsupported extended repodata type for the system repo: \"{}\"."), type_name);
     }
 }
 
-
 void SolvRepo::load_repo_ext(RepodataType type, const RepoDownloader & downloader) {
+    std::string type_name = "";
+    load_repo_ext(type, type_name, downloader);
+}
+
+void SolvRepo::load_repo_ext(RepodataType type, const std::string & in_type_name, const RepoDownloader & downloader) {
     auto & logger = *base->get_logger();
     solv::Pool & pool = type == RepodataType::COMPS ? static_cast<solv::Pool &>(get_comps_pool(base))
                                                     : static_cast<solv::Pool &>(get_rpm_pool(base));
 
-    std::string type_name = repodata_type_to_name(type);
+    std::string type_name = in_type_name.empty() ? repodata_type_to_name(type) : in_type_name;
 
     std::string ext_fn;
 
@@ -375,6 +385,8 @@ void SolvRepo::load_repo_ext(RepodataType type, const RepoDownloader & downloade
         case RepodataType::OTHER:
             res = repo_add_rpmmd(repo, ext_file.get(), 0, REPO_EXTEND_SOLVABLES);
             break;
+        case RepodataType::APPSTREAM:
+            break;
     }
 
     if (res != 0) {
@@ -388,9 +400,9 @@ void SolvRepo::load_repo_ext(RepodataType type, const RepoDownloader & downloade
 
     if (config.get_build_cache_option().get_value()) {
         if (type == RepodataType::COMPS) {
-            write_ext(comps_repo->nrepodata - 1, type);
+            write_ext(comps_repo->nrepodata - 1, type, type_name);
         } else {
-            write_ext(repo->nrepodata - 1, type);
+            write_ext(repo->nrepodata - 1, type, type_name);
         }
     }
 }
@@ -610,14 +622,13 @@ void SolvRepo::write_main(bool load_after_write) {
 }
 
 
-void SolvRepo::write_ext(Id repodata_id, RepodataType type) {
+void SolvRepo::write_ext(Id repodata_id, RepodataType type, const std::string & type_name) {
     libdnf_assert(repodata_id != 0, "0 is not a valid repodata id");
 
     auto & logger = *base->get_logger();
     solv::Pool & pool = type == RepodataType::COMPS ? static_cast<solv::Pool &>(get_comps_pool(base))
                                                     : static_cast<solv::Pool &>(get_rpm_pool(base));
 
-    const std::string type_name = repodata_type_to_name(type);
     const auto solvfile_path = solv_file_path(type_name.c_str());
     const auto solvfile_parent_dir = solvfile_path.parent_path();
 

libdnf5/repo/solv_repo.hpp

@@ -52,7 +52,7 @@ struct SolvUserdata {
 namespace libdnf5::repo {
 
 using LibsolvRepo = ::Repo;
-enum class RepodataType { FILELISTS, PRESTO, UPDATEINFO, COMPS, OTHER };
+enum class RepodataType { FILELISTS, PRESTO, UPDATEINFO, COMPS, OTHER, APPSTREAM };
 
 
 class SolvError : public Error {
@@ -73,6 +73,7 @@ class SolvRepo {
 
     /// Loads additional metadata (filelist, others, ...) from available repo.
     void load_repo_ext(RepodataType type, const RepoDownloader & downloader);
+    void load_repo_ext(RepodataType type, const std::string & in_type_name, const RepoDownloader & downloader);
 
     /// Loads system repository into the pool.
     ///
@@ -128,7 +129,7 @@ class SolvRepo {
     void write_main(bool load_after_write);
 
     /// Writes libsolv's .solvx cache file with extended libsolv repodata.
-    void write_ext(Id repodata_id, RepodataType type);
+    void write_ext(Id repodata_id, RepodataType type, const std::string & type_name);
 
     std::string solv_file_name(const char * type = nullptr);
     std::filesystem::path solv_file_path(const char * type = nullptr);