Merge 'sstables: change make_descriptor() to accept fs::path' from Ke…

…fu Chai

to lower the programmer's cognitive load. as programmer might want
to pass the full path as the `fname` when calling
`make_descriptor(sstring sstdir, sstring fname)`, but this overload
only accepts the filename component as its second parameter. a
single `path` parameter would be easier to work with.

Refs scylladb#15187

Closes scylladb#15188

* github.com:scylladb/scylladb:
  sstable: add samples of fname to be matched by regex
  sstables: change make_descriptor() to accept fs::path
  sstables: switch entry_descriptor(sstring..) to std::string_view
  sstables: change make_descriptor() to accept fs::path

replica/table.cc

@@ -1901,7 +1901,7 @@ future<std::unordered_map<sstring, table::snapshot_details>> table::get_snapshot
                         // All the others should just generate an exception: there is something wrong, so don't blindly
                         // add it to the size.
                         if (name != "manifest.json" && name != "schema.cql") {
-                            sstables::entry_descriptor::make_descriptor(snapshot_dir.native(), name);
+                            sstables::entry_descriptor::make_descriptor(snapshot_dir / name);
                             all_snapshots.at(snapshot_name).total += size;
                         } else {
                             size = 0;

sstables/open_info.hh

@@ -30,13 +30,13 @@ struct entry_descriptor {
     sstable_format_types format;
     component_type component;
 
-    static entry_descriptor make_descriptor(sstring sstdir, sstring fname);
+    static entry_descriptor make_descriptor(const std::filesystem::path& sst_path);
 
     // Use the given ks and cf and don't attempt to extract it from the dir path.
     // This allows loading sstables from any path, but the filename still has to be valid.
-    static entry_descriptor make_descriptor(sstring sstdir, sstring fname, sstring ks, sstring cf);
+    static entry_descriptor make_descriptor(const std::filesystem::path& sst_path, sstring ks, sstring cf);
 
-    entry_descriptor(sstring sstdir, sstring ks, sstring cf, generation_type generation,
+    entry_descriptor(std::string_view sstdir, sstring ks, sstring cf, generation_type generation,
                      sstable_version_types version, sstable_format_types format,
                      component_type component)
         : sstdir(sstdir), ks(ks), cf(cf), generation(generation), version(version), format(format), component(component) {}

sstables/sstable_directory.cc

@@ -244,8 +244,9 @@ future<> sstable_directory::filesystem_components_lister::process(sstable_direct
             if (!de) {
                 break;
             }
-            auto comps = sstables::entry_descriptor::make_descriptor(_directory.native(), de->name);
-            handle(std::move(comps), _directory / de->name);
+            auto component_path = _directory / de->name;
+            auto comps = sstables::entry_descriptor::make_descriptor(component_path);
+            handle(std::move(comps), component_path);
         }
     } catch (...) {
         ex = std::current_exception();
@@ -405,7 +406,7 @@ sstable_directory::collect_output_unshared_sstables(std::vector<sstables::shared
         }
 
         dirlog.trace("Collected output SSTable {} is remote. Storing it", sst->get_filename());
-        _unshared_remote_sstables[shard].push_back(sstables::entry_descriptor::make_descriptor(_sstable_dir.native(), sst->component_basename(component_type::Data)));
+        _unshared_remote_sstables[shard].push_back(sstables::entry_descriptor::make_descriptor(_sstable_dir / sst->component_basename(component_type::Data)));
         return make_ready_future<>();
     });
 }

sstables/sstables.cc

@@ -2101,7 +2101,11 @@ sstable::make_crawling_reader(
     return kl::make_crawling_reader(shared_from_this(), std::move(schema), std::move(permit), std::move(trace_state), monitor);
 }
 
-static entry_descriptor make_entry_descriptor(sstring sstdir, sstring fname, sstring* const provided_ks, sstring* const provided_cf) {
+static entry_descriptor make_entry_descriptor(std::string_view sstdir, std::string_view fname, sstring* const provided_ks, sstring* const provided_cf) {
+    // examples of fname look like
+    //   la-42-big-Data.db
+    //   ka-42-big-Data.db
+    //   me-3g8w_00qf_4pbog2i7h2c7am0uoe-big-Data.db
     static boost::regex la_mx("(la|m[cde])-([^-]+)-(\\w+)-(.*)");
     static boost::regex ka("(\\w+)-(\\w+)-ka-(\\d+)-(.*)");
 
@@ -2156,12 +2160,12 @@ static entry_descriptor make_entry_descriptor(sstring sstdir, sstring fname, sst
     return entry_descriptor(sstdir, ks, cf, generation_type::from_string(generation), version, format_from_string(format), sstable::component_from_sstring(version, component));
 }
 
-entry_descriptor entry_descriptor::make_descriptor(sstring sstdir, sstring fname) {
-    return make_entry_descriptor(std::move(sstdir), std::move(fname), nullptr, nullptr);
+entry_descriptor entry_descriptor::make_descriptor(const std::filesystem::path& sst_path) {
+    return make_entry_descriptor(sst_path.parent_path().native(), sst_path.filename().native(), nullptr, nullptr);
 }
 
-entry_descriptor entry_descriptor::make_descriptor(sstring sstdir, sstring fname, sstring ks, sstring cf) {
-    return make_entry_descriptor(std::move(sstdir), std::move(fname), &ks, &cf);
+entry_descriptor entry_descriptor::make_descriptor(const std::filesystem::path& sst_path, sstring ks, sstring cf) {
+    return make_entry_descriptor(sst_path.parent_path().native(), sst_path.filename().native(), &ks, &cf);
 }
 
 sstable_version_types version_from_string(std::string_view s) {

tools/scylla-sstable.cc

@@ -188,9 +188,8 @@ schema_ptr try_load_schema_autodetect(const bpo::variables_map& app_config) {
     if (app_config.count("sstables")) {
         try {
             auto sst_path = std::filesystem::path(app_config["sstables"].as<std::vector<sstring>>().front());
+            auto ed = sstables::entry_descriptor::make_descriptor(sst_path);
             const auto sst_dir_path = std::filesystem::path(sst_path).remove_filename();
-            const auto sst_filename = sst_path.filename();
-            auto ed = sstables::entry_descriptor::make_descriptor(sst_dir_path.native(), sst_filename.native());
             std::filesystem::path data_dir_path;
             // Detect whether sstable is in root table directory, or in a sub-directory
             // The last component is "" due to the trailing "/" left by "remove_filename()" above.
@@ -253,10 +252,9 @@ const std::vector<sstables::shared_sstable> load_sstables(schema_ptr schema, sst
             }
         }
 
-        const auto dir_path = sst_path.parent_path();
-        const auto sst_filename = sst_path.filename();
 
-        auto ed = sstables::entry_descriptor::make_descriptor(dir_path.c_str(), sst_filename.c_str(), schema->ks_name(), schema->cf_name());
+        auto ed = sstables::entry_descriptor::make_descriptor(sst_path, schema->ks_name(), schema->cf_name());
+        const auto dir_path = sst_path.parent_path();
         data_dictionary::storage_options local;
         auto sst = sst_man.make_sstable(schema, dir_path.c_str(), local, ed.generation, sstables::sstable_state::normal, ed.version, ed.format);