Revert PR 930 (#970)

* revert PR 930

* fix pkg_resources.get_distribution

src/snowflake/snowpark/session.py

@@ -5,7 +5,6 @@
 
 import datetime
 import decimal
-import importlib
 import json
 import logging
 import os
@@ -19,7 +18,7 @@
 from typing import Any, Dict, List, Literal, Optional, Sequence, Set, Tuple, Union
 
 import cloudpickle
-from packaging.requirements import Requirement
+import pkg_resources
 
 from snowflake.connector import ProgrammingError, SnowflakeConnection
 from snowflake.connector.options import installed_pandas, pandas
@@ -811,7 +810,7 @@ def remove_package(self, package: str) -> None:
             >>> len(session.get_packages())
             0
         """
-        package_name = Requirement(package).name.lower().replace("_", "-")
+        package_name = pkg_resources.Requirement.parse(package).key
         if package_name in self._packages:
             self._packages.pop(package_name)
         else:
@@ -892,18 +891,20 @@ def _resolve_packages(
                 package_name = MODULE_NAME_TO_PACKAGE_NAME_MAP.get(
                     package.__name__, package.__name__
                 )
-                package = f"{package_name}=={importlib.metadata.distribution(package_name).version}"
+                package = f"{package_name}=={pkg_resources.get_distribution(package_name).version}"
                 use_local_version = True
             else:
                 package = package.strip().lower()
                 if package.startswith("#"):
                     continue
                 use_local_version = False
-            package_req = Requirement(package)
+            package_req = pkg_resources.Requirement.parse(package)
+            # get the standard package name if there is no underscore
+            # underscores are discouraged in package names, but are still used in Anaconda channel
+            # pkg_resources.Requirement.parse will convert all underscores to dashes
+
             package_name = (
-                package
-                if not use_local_version and "_" in package
-                else package_req.name.lower().replace("_", "-")
+                package if not use_local_version and "_" in package else package_req.key
             )
             package_dict[package] = (package_name, use_local_version, package_req)
 
@@ -924,19 +925,21 @@ def _resolve_packages(
         unsupported_packages: List[str] = []
         for package, package_info in package_dict.items():
             package_name, use_local_version, package_req = package_info
-            package_version_req = package_req.specifier
+            package_version_req = package_req.specs[0][1] if package_req.specs else None
 
             if validate_package:
                 if package_name not in valid_packages or (
                     package_version_req
-                    and not any(
-                        package_version_req.contains(v)
-                        for v in valid_packages[package_name]
-                    )
+                    and not any(v in package_req for v in valid_packages[package_name])
                 ):
+                    version_text = (
+                        f"(version {package_version_req})"
+                        if package_version_req is not None
+                        else ""
+                    )
                     if is_in_stored_procedure():  # pragma: no cover
                         raise RuntimeError(
-                            f"Cannot add package {package_req} because it is not available in Snowflake "
+                            f"Cannot add package {package_name}{version_text} because it is not available in Snowflake "
                             f"and it cannot be installed via pip as you are executing this code inside a stored "
                             f"procedure. You can find the directory of these packages and add it via "
                             f"session.add_import(). See details at "
@@ -947,15 +950,15 @@ def _resolve_packages(
                         and not self._is_anaconda_terms_acknowledged()
                     ):
                         raise RuntimeError(
-                            f"Cannot add package {package_req} because Anaconda terms must be accepted "
+                            f"Cannot add package {package_name}{version_text} because Anaconda terms must be accepted "
                             "by ORGADMIN to use Anaconda 3rd party packages. Please follow the instructions at "
                             "https://docs.snowflake.com/en/developer-guide/udf/python/udf-python-packages.html#using-third-party-packages-from-anaconda."
                         )
                     unsupported_packages.append(package)
                     continue
                 elif not use_local_version:
                     try:
-                        package_client_version = importlib.metadata.distribution(
+                        package_client_version = pkg_resources.get_distribution(
                             package_name
                         ).version
                         if package_client_version not in valid_packages[package_name]:
@@ -965,7 +968,7 @@ def _resolve_packages(
                                 f"requirement '{package}'. Your UDF might not work when the package version "
                                 f"is different between the server and your local environment."
                             )
-                    except importlib.metadata.PackageNotFoundError:
+                    except pkg_resources.DistributionNotFound:
                         _logger.warning(
                             f"Package '{package_name}' is not installed in the local environment. "
                             f"Your UDF might not work when the package is installed on the server "
@@ -987,7 +990,7 @@ def _resolve_packages(
             else:
                 result_dict[package_name] = package
 
-        dependency_packages: Optional[List[Requirement]] = None
+        dependency_packages: Optional[List[pkg_resources.Requirement]] = None
         if len(unsupported_packages) != 0:
             _logger.warning(
                 f"The following packages are not available in Snowflake: {unsupported_packages}. They "
@@ -1037,7 +1040,7 @@ def _upload_unsupported_packages(
         packages: List[str],
         package_table: str,
         force_push: bool = True,
-    ) -> List[Requirement]:
+    ) -> List[pkg_resources.Requirement]:
         """
         Uploads a list of Pypi packages, which are unavailable in Snowflake, to session stage.