allow getting disk usage from database (#131)

Author: malmans2

cacholote/cache.py

@@ -97,7 +97,7 @@ def wrapper(*args: Any, **kwargs: Any) -> Any:
                         return _decode_and_update(session, cache_entry, settings)
                     except decode.DecodeError as ex:
                         warnings.warn(str(ex), UserWarning)
-                        clean._delete_cache_entry(session, cache_entry)
+                        clean._delete_cache_entries(session, cache_entry)
 
         result = func(*args, **kwargs)
         cache_entry = database.CacheEntry(

cacholote/clean.py

@@ -20,6 +20,7 @@
 import posixpath
 from typing import Any, Callable, Literal, Optional
 
+import fsspec
 import pydantic
 import sqlalchemy as sa
 import sqlalchemy.orm
@@ -35,7 +36,9 @@
 )
 
 
-def _get_files_from_cache_entry(cache_entry: database.CacheEntry) -> dict[str, str]:
+def _get_files_from_cache_entry(
+    cache_entry: database.CacheEntry, key: str | None
+) -> dict[str, Any]:
     result = cache_entry.result
     if not isinstance(result, (list, tuple, set)):
         result = [result]
@@ -48,27 +51,57 @@ def _get_files_from_cache_entry(cache_entry: database.CacheEntry) -> dict[str, s
             and obj["callable"] in FILE_RESULT_CALLABLES
         ):
             fs, urlpath = extra_encoders._get_fs_and_urlpath(*obj["args"][:2])
-            files[fs.unstrip_protocol(urlpath)] = obj["args"][0]["type"]
+            value = obj["args"][0]
+            if key is not None:
+                value = value[key]
+            files[fs.unstrip_protocol(urlpath)] = value
     return files
 
 
-def _delete_cache_entry(
-    session: sa.orm.Session, cache_entry: database.CacheEntry
+def _remove_files(
+    fs: fsspec.AbstractFileSystem,
+    files: list[str],
+    max_tries: int = 10,
+    **kwargs: Any,
 ) -> None:
-    fs, _ = utils.get_cache_files_fs_dirname()
-    files_to_delete = _get_files_from_cache_entry(cache_entry)
-    logger = config.get().logger
+    assert max_tries >= 1
+    if not files:
+        return
+
+    config.get().logger.info("deleting files", n_files_to_delete=len(files), **kwargs)
+
+    n_tries = 0
+    while files:
+        n_tries += 1
+        try:
+            fs.rm(files, **kwargs)
+            return
+        except FileNotFoundError:
+            # Another concurrent process might have deleted files
+            if n_tries >= max_tries:
+                raise
+            files = [file for file in files if fs.exists(file)]
 
-    # First, delete database entry
-    logger.info("deleting cache entry", cache_entry=cache_entry)
-    session.delete(cache_entry)
+
+def _delete_cache_entries(
+    session: sa.orm.Session, *cache_entries: database.CacheEntry
+) -> None:
+    fs, _ = utils.get_cache_files_fs_dirname()
+    files_to_delete = []
+    dirs_to_delete = []
+    for cache_entry in cache_entries:
+        session.delete(cache_entry)
+
+        files = _get_files_from_cache_entry(cache_entry, key="type")
+        for file, file_type in files.items():
+            if file_type == "application/vnd+zarr":
+                dirs_to_delete.append(file)
+            else:
+                files_to_delete.append(file)
     database._commit_or_rollback(session)
 
-    # Then, delete files
-    for urlpath, file_type in files_to_delete.items():
-        if fs.exists(urlpath):
-            logger.info("deleting cache file", urlpath=urlpath)
-            fs.rm(urlpath, recursive=file_type == "application/vnd+zarr")
+    _remove_files(fs, files_to_delete, recursive=False)
+    _remove_files(fs, dirs_to_delete, recursive=True)
 
 
 def delete(func_to_del: str | Callable[..., Any], *args: Any, **kwargs: Any) -> None:
@@ -88,19 +121,20 @@ def delete(func_to_del: str | Callable[..., Any], *args: Any, **kwargs: Any) ->
         for cache_entry in session.scalars(
             sa.select(database.CacheEntry).filter(database.CacheEntry.key == hexdigest)
         ):
-            _delete_cache_entry(session, cache_entry)
+            _delete_cache_entries(session, cache_entry)
 
 
 class _Cleaner:
-    def __init__(self, depth: int) -> None:
+    def __init__(self, depth: int, use_database: bool) -> None:
         self.logger = config.get().logger
         self.fs, self.dirname = utils.get_cache_files_fs_dirname()
 
         self.urldir = self.fs.unstrip_protocol(self.dirname)
 
         self.logger.info("getting disk usage")
         self.file_sizes: dict[str, int] = collections.defaultdict(int)
-        for path, size in self.fs.du(self.dirname, total=False).items():
+        du = self.known_files if use_database else self.fs.du(self.dirname, total=False)
+        for path, size in du.items():
             # Group dirs
             urlpath = self.fs.unstrip_protocol(path)
             parts = urlpath.replace(self.urldir, "", 1).strip("/").split("/")
@@ -120,6 +154,16 @@ def log_disk_usage(self) -> None:
     def stop_cleaning(self, maxsize: int) -> bool:
         return self.disk_usage <= maxsize
 
+    @property
+    def known_files(self) -> dict[str, int]:
+        known_files: dict[str, int] = {}
+        with config.get().instantiated_sessionmaker() as session:
+            for cache_entry in session.scalars(sa.select(database.CacheEntry)):
+                known_files.update(
+                    _get_files_from_cache_entry(cache_entry, key="file:size")
+                )
+        return known_files
+
     def get_unknown_files(self, lock_validity_period: float | None) -> set[str]:
         self.logger.info("getting unknown files")
 
@@ -137,25 +181,15 @@ def get_unknown_files(self, lock_validity_period: float | None) -> set[str]:
                     locked_files.add(urlpath)
                     locked_files.add(urlpath.rsplit(".lock", 1)[0])
 
-        if unknown_files := (set(self.file_sizes) - locked_files):
-            with config.get().instantiated_sessionmaker() as session:
-                for cache_entry in session.scalars(sa.select(database.CacheEntry)):
-                    for known_file in _get_files_from_cache_entry(cache_entry):
-                        unknown_files.discard(known_file)
-                    if not unknown_files:
-                        break
-        return unknown_files
+        return set(self.file_sizes) - locked_files - set(self.known_files)
 
     def delete_unknown_files(
         self, lock_validity_period: float | None, recursive: bool
     ) -> None:
         unknown_files = self.get_unknown_files(lock_validity_period)
         for urlpath in unknown_files:
             self.pop_file_size(urlpath)
-        self.remove_files(
-            list(unknown_files),
-            recursive=recursive,
-        )
+        _remove_files(self.fs, list(unknown_files), recursive=recursive)
         self.log_disk_usage()
 
     @staticmethod
@@ -207,30 +241,6 @@ def _get_method_sorters(
         sorters.append(database.CacheEntry.expiration)
         return sorters
 
-    def remove_files(
-        self,
-        files: list[str],
-        max_tries: int = 10,
-        **kwargs: Any,
-    ) -> None:
-        assert max_tries >= 1
-        if not files:
-            return
-
-        self.logger.info("deleting files", n_files_to_delete=len(files), **kwargs)
-
-        n_tries = 0
-        while files:
-            n_tries += 1
-            try:
-                self.fs.rm(files, **kwargs)
-                return
-            except FileNotFoundError:
-                # Another concurrent process might have deleted files
-                if n_tries >= max_tries:
-                    raise
-                files = [file for file in files if self.fs.exists(file)]
-
     def delete_cache_files(
         self,
         maxsize: int,
@@ -244,37 +254,27 @@ def delete_cache_files(
         if self.stop_cleaning(maxsize):
             return
 
-        files_to_delete = []
-        dirs_to_delete = []
+        entries_to_delete = []
         self.logger.info("getting cache entries to delete")
-        n_entries_to_delete = 0
         with config.get().instantiated_sessionmaker() as session:
             for cache_entry in session.scalars(
                 sa.select(database.CacheEntry).filter(*filters).order_by(*sorters)
             ):
-                files = _get_files_from_cache_entry(cache_entry)
+                files = _get_files_from_cache_entry(cache_entry, key="file:size")
                 if any(file.startswith(self.urldir) for file in files):
-                    n_entries_to_delete += 1
-                    session.delete(cache_entry)
-
-                    for file, file_type in files.items():
+                    entries_to_delete.append(cache_entry)
+                    for file in files:
                         self.pop_file_size(file)
-                        if file_type == "application/vnd+zarr":
-                            dirs_to_delete.append(file)
-                        else:
-                            files_to_delete.append(file)
 
                 if self.stop_cleaning(maxsize):
                     break
 
-            if n_entries_to_delete:
+            if entries_to_delete:
                 self.logger.info(
-                    "deleting cache entries", n_entries_to_delete=n_entries_to_delete
+                    "deleting cache entries", n_entries_to_delete=len(entries_to_delete)
                 )
-            database._commit_or_rollback(session)
+            _delete_cache_entries(session, *entries_to_delete)
 
-        self.remove_files(files_to_delete, recursive=False)
-        self.remove_files(dirs_to_delete, recursive=True)
         self.log_disk_usage()
 
         if not self.stop_cleaning(maxsize):
@@ -296,6 +296,7 @@ def clean_cache_files(
     tags_to_clean: list[str | None] | None = None,
     tags_to_keep: list[str | None] | None = None,
     depth: int = 1,
+    use_database: bool = False,
 ) -> None:
     """Clean cache files.
 
@@ -318,8 +319,15 @@ def clean_cache_files(
         tags_to_clean and tags_to_keep are mutually exclusive.
     depth: int, default: 1
         depth for grouping cache files
+    use_database: bool, default: False
+        Whether to infer disk usage from the cacholote database
     """
-    cleaner = _Cleaner(depth=depth)
+    if use_database and delete_unknown_files:
+        raise ValueError(
+            "'use_database' and 'delete_unknown_files' are mutually exclusive"
+        )
+
+    cleaner = _Cleaner(depth=depth, use_database=use_database)
 
     if delete_unknown_files:
         cleaner.delete_unknown_files(lock_validity_period, recursive)
@@ -352,15 +360,15 @@ def clean_invalid_cache_entries(
             for cache_entry in session.scalars(
                 sa.select(database.CacheEntry).filter(*filters)
             ):
-                _delete_cache_entry(session, cache_entry)
+                _delete_cache_entries(session, cache_entry)
 
     if try_decode:
         with config.get().instantiated_sessionmaker() as session:
             for cache_entry in session.scalars(sa.select(database.CacheEntry)):
                 try:
                     decode.loads(cache_entry._result_as_string)
                 except decode.DecodeError:
-                    _delete_cache_entry(session, cache_entry)
+                    _delete_cache_entries(session, cache_entry)
 
 
 def expire_cache_entries(
@@ -379,15 +387,14 @@ def expire_cache_entries(
     if after is not None:
         filters.append(database.CacheEntry.created_at > after)
 
-    count = 0
     with config.get().instantiated_sessionmaker() as session:
-        for cache_entry in session.scalars(
-            sa.select(database.CacheEntry).filter(*filters)
-        ):
-            count += 1
-            if delete:
-                session.delete(cache_entry)
-            else:
+        cache_entries = list(
+            session.scalars(sa.select(database.CacheEntry).filter(*filters))
+        )
+        if delete:
+            _delete_cache_entries(session, *cache_entries)
+        else:
+            for cache_entry in cache_entries:
                 cache_entry.expiration = now
-        database._commit_or_rollback(session)
-    return count
+            database._commit_or_rollback(session)
+    return len(cache_entries)

tests/test_60_clean.py

@@ -41,12 +41,14 @@ def cached_now() -> datetime.datetime:
 @pytest.mark.parametrize("method", ["LRU", "LFU"])
 @pytest.mark.parametrize("set_cache", ["file", "cads"], indirect=True)
 @pytest.mark.parametrize("folder,depth", [("", 1), ("", 2), ("foo", 2)])
+@pytest.mark.parametrize("use_database", [True, False])
 def test_clean_cache_files(
     tmp_path: pathlib.Path,
     set_cache: str,
     method: Literal["LRU", "LFU"],
     folder: str,
     depth: int,
+    use_database: bool,
 ) -> None:
     con = config.get().engine.raw_connection()
     cur = con.cursor()
@@ -66,12 +68,12 @@ def test_clean_cache_files(
         assert set(fs.ls(dirname)) == {lru_path, lfu_path}
 
     # Do not clean
-    clean.clean_cache_files(2, method=method, depth=depth)
+    clean.clean_cache_files(2, method=method, depth=depth, use_database=use_database)
     cur.execute("SELECT COUNT(*) FROM cache_entries", ())
     assert cur.fetchone() == (fs.du(dirname),) == (2,)
 
     # Delete one file
-    clean.clean_cache_files(1, method=method, depth=depth)
+    clean.clean_cache_files(1, method=method, depth=depth, use_database=use_database)
     cur.execute("SELECT COUNT(*) FROM cache_entries", ())
     assert cur.fetchone() == (fs.du(dirname),) == (1,)
     assert not fs.exists(lru_path if method == "LRU" else lfu_path)