Model versioning (#8324)

* fix typo

* rm use_cdn & references, and implement new hf_bucket_url

* I'm pretty sure we don't need to `read` this file

* same here

* [BIG] file_utils.networking: do not gobble up errors anymore

* Fix CI 😇

* Apply suggestions from code review

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Tiny doc tweak

* Add doc + pass kwarg everywhere

* Add more tests and explain

cc @sshleifer let me know if better

Co-Authored-By: Sam Shleifer <sshleifer@gmail.com>

* Also implement revision in pipelines

In the case where we're passing a task name or a string model identifier

* Fix CI 😇

* Fix CI

* [hf_api] new methods + command line implem

* make style

* Final endpoints post-migration

* Fix post-migration

* Py3.6 compat

cc @stefan-it

Thank you @stas00

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
Co-authored-by: Sam Shleifer <sshleifer@gmail.com>

src/transformers/configuration_utils.py

@@ -311,6 +311,10 @@ class PretrainedConfig(object):
             proxies (:obj:`Dict[str, str]`, `optional`):
                 A dictionary of proxy servers to use by protocol or endpoint, e.g., :obj:`{'http': 'foo.bar:3128',
                 'http://hostname': 'foo.bar:4012'}.` The proxies are used on each request.
+            revision(:obj:`str`, `optional`, defaults to :obj:`"main"`):
+                The specific model version to use. It can be a branch name, a tag name, or a commit id, since we use a
+                git-based system for storing models and other artifacts on huggingface.co, so ``revision`` can be any
+                identifier allowed by git.
             return_unused_kwargs (:obj:`bool`, `optional`, defaults to :obj:`False`):
                 If :obj:`False`, then this function returns just the final configuration object.
 
@@ -362,6 +366,7 @@ class PretrainedConfig(object):
         resume_download = kwargs.pop("resume_download", False)
         proxies = kwargs.pop("proxies", None)
         local_files_only = kwargs.pop("local_files_only", False)
+        revision = kwargs.pop("revision", None)
 
         if os.path.isdir(pretrained_model_name_or_path):
             config_file = os.path.join(pretrained_model_name_or_path, CONFIG_NAME)
@@ -369,7 +374,7 @@ class PretrainedConfig(object):
             config_file = pretrained_model_name_or_path
         else:
             config_file = hf_bucket_url(
-                pretrained_model_name_or_path, filename=CONFIG_NAME, use_cdn=False, mirror=None
+                pretrained_model_name_or_path, filename=CONFIG_NAME, revision=revision, mirror=None
             )
 
         try:
@@ -383,11 +388,10 @@ class PretrainedConfig(object):
                 local_files_only=local_files_only,
             )
             # Load config dict
-            if resolved_config_file is None:
-                raise EnvironmentError
             config_dict = cls._dict_from_json_file(resolved_config_file)
 
-        except EnvironmentError:
+        except EnvironmentError as err:
+            logger.error(err)
             msg = (
                 f"Can't load config for '{pretrained_model_name_or_path}'. Make sure that:\n\n"
                 f"- '{pretrained_model_name_or_path}' is a correct model identifier listed on 'https://huggingface.co/models'\n\n"