Add option to disable checksums for external files and blobs

CHANGELOG.md

@@ -1,8 +1,11 @@
 ## Release notes
 
 ### 0.13.6 -- Jun 13, 2022
-* Add - unified package level logger for package (#667) PR #1031
-* Update - swap various datajoint messages, warnings, etc. to use the new logger. (#667) PR #1031
+* Add - Config option to set threshold for when to stop using checksums for filepath stores. PR #1025
+* Add - Unified package level logger for package (#667) PR #1031
+* Update - Swap various datajoint messages, warnings, etc. to use the new logger. (#667) PR #1031
+* Bugfix - Fix query caching deleting non-datajoint files PR #1027
+* Update - Minimum Python version for Datajoint-Python is now 3.7 PR #1027
 
 ### 0.13.5 -- May 19, 2022
 * Update - Import ABC from collections.abc for Python 3.10 compatibility

datajoint/external.py

@@ -1,6 +1,7 @@
 from pathlib import Path, PurePosixPath, PureWindowsPath
 from collections.abc import Mapping
 from tqdm import tqdm
+import logging
 from .settings import config
 from .errors import DataJointError, MissingExternalFile
 from .hash import uuid_from_buffer, uuid_from_file
@@ -10,6 +11,8 @@
 from . import s3
 from .utils import safe_write, safe_copy
 
+logger = logging.getLogger(__name__.split(".")[0])
+
 CACHE_SUBFOLDING = (
     2,
     2,
@@ -72,9 +75,7 @@ def definition(self):
 
     @property
     def table_name(self):
-        return "{external_table_root}_{store}".format(
-            external_table_root=EXTERNAL_TABLE_ROOT, store=self.store
-        )
+        return f"{EXTERNAL_TABLE_ROOT}_{self.store}"
 
     @property
     def s3(self):
@@ -276,9 +277,7 @@ def upload_filepath(self, local_filepath):
             # the tracking entry exists, check that it's the same file as before
             if contents_hash != check_hash[0]:
                 raise DataJointError(
-                    "A different version of '{file}' has already been placed.".format(
-                        file=relative_filepath
-                    )
+                    f"A different version of '{relative_filepath}' has already been placed."
                 )
         else:
             # upload the file and create its tracking entry
@@ -304,27 +303,43 @@ def download_filepath(self, filepath_hash):
         :param filepath_hash: The hash (UUID) of the relative_path
         :return: hash (UUID) of the contents of the downloaded file or Nones
         """
+
+        def _need_checksum(local_filepath, expected_size):
+            limit = config.get("filepath_checksum_size_limit")
+            actual_size = Path(local_filepath).stat().st_size
+            if expected_size != actual_size:
+                # this should never happen without outside interference
+                raise DataJointError(
+                    f"'{local_filepath}' downloaded but size did not match."
+                )
+            return limit is None or actual_size < limit
+
         if filepath_hash is not None:
-            relative_filepath, contents_hash = (self & {"hash": filepath_hash}).fetch1(
-                "filepath", "contents_hash"
-            )
+            relative_filepath, contents_hash, size = (
+                self & {"hash": filepath_hash}
+            ).fetch1("filepath", "contents_hash", "size")
             external_path = self._make_external_filepath(relative_filepath)
             local_filepath = Path(self.spec["stage"]).absolute() / relative_filepath
-            file_exists = (
-                Path(local_filepath).is_file()
-                and uuid_from_file(local_filepath) == contents_hash
+
+            file_exists = Path(local_filepath).is_file() and (
+                not _need_checksum(local_filepath, size)
+                or uuid_from_file(local_filepath) == contents_hash
             )
+
             if not file_exists:
                 self._download_file(external_path, local_filepath)
-                checksum = uuid_from_file(local_filepath)
                 if (
-                    checksum != contents_hash
-                ):  # this should never happen without outside interference
+                    _need_checksum(local_filepath, size)
+                    and uuid_from_file(local_filepath) != contents_hash
+                ):
+                    # this should never happen without outside interference
                     raise DataJointError(
-                        "'{file}' downloaded but did not pass checksum'".format(
-                            file=local_filepath
-                        )
+                        f"'{local_filepath}' downloaded but did not pass checksum."
                     )
+            if not _need_checksum(local_filepath, size):
+                logger.warning(
+                    f"Skipped checksum for file with hash: {contents_hash}, and path: {local_filepath}"
+                )
             return str(local_filepath), contents_hash
 
     # --- UTILITIES ---
@@ -402,7 +417,7 @@ def delete(
         delete_external_files=None,
         limit=None,
         display_progress=True,
-        errors_as_string=True
+        errors_as_string=True,
     ):
         """
 

datajoint/settings.py

@@ -46,6 +46,7 @@
         "display.show_tuple_count": True,
         "database.use_tls": None,
         "enable_python_native_blobs": True,  # python-native/dj0 encoding support
+        "filepath_checksum_size_limit": None,  # file size limit for when to disable checksums
     }
 )
 

docs-parts/intro/Releases_lang1.rst

@@ -1,7 +1,10 @@
 0.13.6 -- Jun 13, 2022
 ----------------------
-* Add - unified package level logger for package (#667) PR #1031
-* Update - swap various datajoint messages, warnings, etc. to use the new logger. (#667) PR #1031
+* Add - Config option to set threshold for when to stop using checksums for filepath stores. PR #1025
+* Add - Unified package level logger for package (#667) PR #1031
+* Update - Swap various datajoint messages, warnings, etc. to use the new logger. (#667) PR #1031
+* Bugfix - Fix query caching deleting non-datajoint files PR #1027
+* Update - Minimum Python version for Datajoint-Python is now 3.7 PR #1027
 
 0.13.5 -- May 19, 2022
 ----------------------

tests/test_filepath.py

@@ -3,8 +3,11 @@
 import os
 from pathlib import Path
 import random
-
 from .schema_external import schema, Filepath, FilepathS3, stores_config
+import logging
+import io
+
+logger = logging.getLogger("datajoint")
 
 
 def setUp(self):
@@ -132,7 +135,9 @@ def test_duplicate_error_s3():
     test_duplicate_error(store="repo-s3")
 
 
-def test_filepath_class(table=Filepath(), store="repo"):
+def test_filepath_class(table=Filepath(), store="repo", verify_checksum=True):
+    if not verify_checksum:
+        dj.config["filepath_checksum_size_limit"] = 0
     dj.errors._switch_filepath_types(True)
     stage_path = dj.config["stores"][store]["stage"]
     # create a mock file
@@ -169,6 +174,7 @@ def test_filepath_class(table=Filepath(), store="repo"):
     # delete from external table
     table.external[store].delete(delete_external_files=True)
     dj.errors._switch_filepath_types(False)
+    dj.config["filepath_checksum_size_limit"] = None
 
 
 def test_filepath_class_again():
@@ -185,6 +191,24 @@ def test_filepath_class_s3_again():
     test_filepath_class(FilepathS3(), "repo-s3")
 
 
+def test_filepath_class_no_checksum():
+    log_capture = io.StringIO()
+    stream_handler = logging.StreamHandler(log_capture)
+    log_format = logging.Formatter(
+        "[%(asctime)s][%(funcName)s][%(levelname)s]: %(message)s"
+    )
+    stream_handler.setFormatter(log_format)
+    stream_handler.set_name("test_limit_warning")
+    logger.addHandler(stream_handler)
+    test_filepath_class(verify_checksum=False)
+    log_contents = log_capture.getvalue()
+    log_capture.close()
+    for handler in logger.handlers:  # Clean up handler
+        if handler.name == "test_limit_warning":
+            logger.removeHandler(handler)
+    assert "Skipped checksum for file with hash:" in log_contents
+
+
 def test_filepath_cleanup(table=Filepath(), store="repo"):
     """test deletion of filepath entries from external table"""