Move imports in functions to top level or annotate why they can't be moved

dandi/cli/cmd_digest.py

@@ -22,6 +22,7 @@
 @map_to_click_exceptions
 def digest(paths: tuple[str, ...], digest_alg: str) -> None:
     """Calculate file digests"""
+    # Avoid heavy import by importing within function:
     from ..support.digests import get_digest
 
     for p in paths:

dandi/cli/cmd_download.py

@@ -7,6 +7,7 @@
 
 from .base import ChoiceList, IntColonInt, instance_option, map_to_click_exceptions
 from ..dandiarchive import _dandi_url_parser, parse_dandi_url
+from ..dandiset import Dandiset
 from ..download import DownloadExisting, DownloadFormat, PathType
 from ..utils import get_instance
 
@@ -123,8 +124,6 @@ def download(
                         f"{u} does not point to {dandi_instance!r} instance"
                     )
         else:
-            from ..dandiset import Dandiset
-
             try:
                 dandiset_id = Dandiset(os.curdir).identifier
             except ValueError:

dandi/cli/cmd_ls.py

@@ -3,12 +3,16 @@
 import os.path as op
 
 import click
+from dandischema import models
 
 from .base import devel_option, lgr, map_to_click_exceptions
+from .formatter import JSONFormatter, JSONLinesFormatter, PYOUTFormatter, YAMLFormatter
 from ..consts import ZARR_EXTENSIONS, metadata_all_fields
 from ..dandiarchive import DandisetURL, _dandi_url_parser, parse_dandi_url
+from ..dandiset import Dandiset
 from ..misctypes import Digest
-from ..utils import is_url
+from ..support.pyout import PYOUT_SHORT_NAMES, PYOUT_SHORT_NAMES_rev
+from ..utils import find_files, is_url
 
 # TODO: all the recursion options etc
 
@@ -87,21 +91,8 @@ def ls(
     """List .nwb files and dandisets metadata."""
 
     # TODO: more logical ordering in case of fields = None
-    from .formatter import (
-        JSONFormatter,
-        JSONLinesFormatter,
-        PYOUTFormatter,
-        YAMLFormatter,
-    )
-
-    # TODO: avoid
-    from ..support.pyout import PYOUT_SHORT_NAMES_rev
-    from ..utils import find_files
-
     common_fields = ("path", "size")
     if schema is not None:
-        from dandischema import models
-
         all_fields = tuple(
             sorted(
                 set(common_fields)
@@ -249,8 +240,6 @@ def _add_exc_error(asset, rec, errors, exc):
 
 
 def display_known_fields(all_fields):
-    from ..support.pyout import PYOUT_SHORT_NAMES
-
     # Display all known fields
     click.secho("Known fields:")
     for field in all_fields:
@@ -330,7 +319,7 @@ def flatten_meta_to_pyout(meta):
 def get_metadata_ls(
     path, keys, errors, flatten=False, schema=None, use_fake_digest=False
 ):
-    from ..dandiset import Dandiset
+    # Avoid heavy import by importing within function:
     from ..metadata.nwb import get_metadata, nwb2asset
     from ..pynwb_utils import get_nwb_version, ignore_benign_pynwb_warnings
     from ..support.digests import get_digest

dandi/cli/cmd_shell_completion.py

@@ -48,6 +48,7 @@ def shell_completion(shell):
         varfmt = "{shell}_source"
     os.environ["_DANDI_COMPLETE"] = varfmt.format(shell=shell)
 
+    # Avoid circular import by importing within function:
     from .command import main
 
     main.main(args=[])

dandi/cli/cmd_upload.py

@@ -91,6 +91,7 @@ def upload(
     directories starting with a period) will be considered for the upload.  You
     can point to specific files you would like to validate and have uploaded.
     """
+    # Avoid heavy imports by importing with function:
     from ..upload import upload
 
     if jobs_pair is None:

dandi/cli/cmd_validate.py

@@ -11,6 +11,7 @@
 
 from .base import devel_debug_option, devel_option, map_to_click_exceptions
 from ..utils import pluralize
+from ..validate import validate as validate_
 from ..validate_types import Severity, ValidationResult
 
 
@@ -101,8 +102,8 @@ def validate(
 
     Exits with non-0 exit code if any file is not compliant.
     """
+    # Avoid heavy import by importing within function:
     from ..pynwb_utils import ignore_benign_pynwb_warnings
-    from ..validate import validate as validate_
 
     # Don't log validation warnings, as this command reports them to the user
     # anyway:

dandi/cli/command.py

@@ -15,7 +15,7 @@
 
 from .base import lgr, map_to_click_exceptions
 from .. import __version__, set_logger_level
-from ..utils import get_module_version
+from ..utils import check_dandi_version, get_module_version, setup_exceptionhook
 
 # Delay imports leading to import of heavy modules such as pynwb and h5py
 # Import at the point of use
@@ -130,12 +130,8 @@ def main(ctx, log_level, pdb=False):
 
     if pdb:
         map_to_click_exceptions._do_map = False
-        from ..utils import setup_exceptionhook
-
         setup_exceptionhook()
 
-    from ..utils import check_dandi_version
-
     check_dandi_version()
 
 

dandi/cli/formatter.py

@@ -1,5 +1,9 @@
 import datetime
+import json
 import sys
+from textwrap import indent
+
+import ruamel.yaml
 
 from .. import get_logger
 from ..support import pyout as pyouts
@@ -39,9 +43,6 @@ def __exit__(self, exc_type, exc_value, traceback):
         print("]", file=self.out)
 
     def __call__(self, rec):
-        import json
-        from textwrap import indent
-
         if self.first:
             print(file=self.out)
             self.first = False
@@ -66,8 +67,6 @@ def _serializer(o):
         return o
 
     def __call__(self, rec):
-        import json
-
         print(
             json.dumps(
                 rec, indent=self.indent, sort_keys=True, default=self._serializer
@@ -82,8 +81,6 @@ def __init__(self, out=None):
         self.records = []
 
     def __exit__(self, exc_type, exc_value, traceback):
-        import ruamel.yaml
-
         yaml = ruamel.yaml.YAML(typ="safe")
         yaml.default_flow_style = False
         yaml.dump(self.records, self.out)

dandi/cli/tests/test_cmd_validate.py

@@ -4,8 +4,9 @@
 from click.testing import CliRunner
 import pytest
 
-from ..cmd_validate import validate
+from ..cmd_validate import _process_issues, validate
 from ...tests.fixtures import BIDS_ERROR_TESTDATA_SELECTION
+from ...validate_types import Scope, Severity, ValidationOrigin, ValidationResult
 
 
 @pytest.mark.parametrize("dataset", BIDS_ERROR_TESTDATA_SELECTION)
@@ -67,11 +68,6 @@ def test_validate_nwb_path_grouping(organized_nwb_dir4: Path) -> None:
 
 
 def test_process_issues(capsys):
-    from pathlib import Path
-
-    from ..cmd_validate import _process_issues
-    from ...validate_types import Scope, Severity, ValidationOrigin, ValidationResult
-
     issues = [
         ValidationResult(
             id="NWBI.check_data_orientation",

dandi/dandiapi.py

@@ -1194,6 +1194,7 @@ def upload_raw_asset(
         :param RemoteAsset replace_asset: If set, replace the given asset,
             which must have the same path as the new asset
         """
+        # Avoid circular import by importing within function:
         from .files import LocalAsset, dandi_file
 
         df = dandi_file(filepath)
@@ -1235,6 +1236,7 @@ def iter_upload_raw_asset(
             ``"done"`` and an ``"asset"`` key containing the resulting
             `RemoteAsset`.
         """
+        # Avoid circular import by importing within function:
         from .files import LocalAsset, dandi_file
 
         df = dandi_file(filepath)

dandi/delete.py

@@ -10,7 +10,9 @@
 from .consts import DRAFT, ZARR_EXTENSIONS, DandiInstance, dandiset_metadata_file
 from .dandiapi import DandiAPIClient, RemoteAsset, RemoteDandiset
 from .dandiarchive import BaseAssetIDURL, DandisetURL, ParsedDandiURL, parse_dandi_url
+from .dandiset import Dandiset
 from .exceptions import NotFoundError
+from .support import pyout as pyouts
 from .utils import get_instance, is_url
 
 
@@ -214,8 +216,6 @@ def delete(
                 for r in gen:
                     print(r, flush=True)
         else:
-            from .support import pyout as pyouts
-
             pyout_style = pyouts.get_style(hide_if_missing=False)
             rec_fields = ("path", "status", "message")
             out = pyouts.LogSafeTabular(
@@ -232,8 +232,6 @@ def find_local_asset(filepath: str) -> tuple[str, str]:
     located and the path to the file relative to the root of said Dandiset.  If
     the file is a directory, the path will end with a trailing slash.
     """
-    from .dandiset import Dandiset
-
     path = Path(filepath).absolute()
     dandiset = Dandiset.find(path.parent)
     if dandiset is None:

dandi/download.py

@@ -18,6 +18,7 @@
 from types import TracebackType
 from typing import IO, Any, Literal
 
+from dandischema.digests.dandietag import ETagHashlike
 from dandischema.models import DigestType
 from fasteners import InterProcessLock
 import humanize
@@ -31,6 +32,7 @@
 from .dandiset import Dandiset
 from .exceptions import NotFoundError
 from .files import LocalAsset, find_dandi_files
+from .support import pyout as pyouts
 from .support.iterators import IteratorWithAggregation
 from .support.pyout import naturalsize
 from .utils import (
@@ -91,8 +93,6 @@ def download(
     # TODO: unduplicate with upload. For now stole from that one
     # We will again use pyout to provide a neat table summarizing our progress
     # with upload etc
-    from .support import pyout as pyouts
-
     urls = flattened([urls])
     if not urls:
         # if no paths provided etc, we will download dandiset path
@@ -551,6 +551,7 @@ def _download_file(
       possible checksums or other digests provided for the file. Only one
       will be used to verify download
     """
+    # Avoid heavy import by importing within function:
     from .support.digests import get_digest
 
     if op.lexists(path):
@@ -650,8 +651,6 @@ def _download_file(
         # TODO: reuse that sorting based on speed
         for algo, digest in digests.items():
             if algo == "dandi-etag" and size is not None:
-                from dandischema.digests.dandietag import ETagHashlike
-
                 # Instantiate outside the lambda so that mypy is assured that
                 # `size` is not None:
                 hasher = ETagHashlike(size)
@@ -855,6 +854,7 @@ def _download_zarr(
     lock: Lock,
     jobs: int | None = None,
 ) -> Iterator[dict]:
+    # Avoid heavy import by importing within function:
     from .support.digests import get_zarr_checksum
 
     download_gens = {}

dandi/files/bases.py

@@ -299,6 +299,7 @@ def get_metadata(
 
     def get_digest(self) -> Digest:
         """Calculate a dandi-etag digest for the asset"""
+        # Avoid heavy import by importing within function:
         from dandi.support.digests import get_digest
 
         value = get_digest(self.filepath, digest="dandi-etag")
@@ -331,6 +332,7 @@ def iter_upload(
             ``"done"`` and an ``"asset"`` key containing the resulting
             `RemoteAsset`.
         """
+        # Avoid heavy import by importing within function:
         from dandi.support.digests import get_dandietag
 
         asset_path = metadata.setdefault("path", self.path)
@@ -469,6 +471,7 @@ def get_metadata(
         digest: Digest | None = None,
         ignore_errors: bool = True,
     ) -> BareAsset:
+        # Avoid heavy import by importing within function:
         from dandi.metadata.nwb import nwb2asset
 
         try:
@@ -499,8 +502,10 @@ def get_validation_errors(
         If ``schema_version`` was provided, we only validate basic metadata,
         and completely skip validation using nwbinspector.inspect_nwbfile
         """
+        # Avoid heavy import by importing within function:
         from nwbinspector import Importance, inspect_nwbfile, load_config
 
+        # Avoid heavy import by importing within function:
         from dandi.pynwb_utils import validate as pynwb_validate
 
         errors: list[ValidationResult] = pynwb_validate(
@@ -559,9 +564,9 @@ def get_validation_errors(
                     [e], self.filepath, scope=Scope.FILE
                 )
 
-        from dandi.organize import validate_organized_path
-
+        # Avoid circular imports by importing within function:
         from .bids import NWBBIDSAsset
+        from ..organize import validate_organized_path
 
         if not isinstance(self, NWBBIDSAsset) and self.dandiset_path is not None:
             errors.extend(
@@ -716,6 +721,7 @@ def _check_required_fields(
 
 
 def _get_nwb_inspector_version():
+    # Avoid heavy import by importing within function:
     from nwbinspector.utils import get_package_version
 
     global _current_nwbinspector_version

dandi/files/zarr.py

@@ -93,7 +93,7 @@ def get_digest(self) -> Digest:
         directory, the algorithm will be the Dandi Zarr checksum algorithm; if
         it is a file, it will be MD5.
         """
-
+        # Avoid heavy import by importing within function:
         from dandi.support.digests import get_digest, get_zarr_checksum
 
         if self.is_dir():
@@ -152,6 +152,7 @@ def stat(self) -> ZarrStat:
         """Return various details about the Zarr asset"""
 
         def dirstat(dirpath: LocalZarrEntry) -> ZarrStat:
+            # Avoid heavy import by importing within function:
             from dandi.support.digests import md5file_nocache
 
             size = 0
@@ -178,6 +179,7 @@ def dirstat(dirpath: LocalZarrEntry) -> ZarrStat:
 
     def get_digest(self) -> Digest:
         """Calculate a dandi-zarr-checksum digest for the asset"""
+        # Avoid heavy import by importing within function:
         from dandi.support.digests import get_zarr_checksum
 
         return Digest.dandi_zarr(get_zarr_checksum(self.filepath))
@@ -197,6 +199,7 @@ def get_validation_errors(
         schema_version: str | None = None,
         devel_debug: bool = False,
     ) -> list[ValidationResult]:
+        # Avoid heavy import by importing within function:
         import zarr
 
         errors: list[ValidationResult] = []
@@ -591,6 +594,7 @@ def register(self, e: LocalZarrEntry, digest: str | None = None) -> None:
 
     @staticmethod
     def _mkitem(e: LocalZarrEntry) -> UploadItem:
+        # Avoid heavy import by importing within function:
         from dandi.support.digests import md5file_nocache
 
         digest = md5file_nocache(e.filepath)
@@ -643,6 +647,7 @@ def upload_request(self) -> dict[str, str]:
 def _cmp_digests(
     asset_path: str, local_entry: LocalZarrEntry, remote_digest: str
 ) -> tuple[LocalZarrEntry, str, bool]:
+    # Avoid heavy import by importing within function:
     from dandi.support.digests import md5file_nocache
 
     local_digest = md5file_nocache(local_entry.filepath)