Fix client imports

Fix imports to be vendoring compatible.

Signed-off-by: Teodora Sechkova <tsechkova@vmware.com>

tuf/client_rework/download.py

@@ -28,12 +28,10 @@
 import timeit
 import urllib
 
-import securesystemslib
-import securesystemslib.util
+from securesystemslib import formats as sslib_formats
 
 import tuf
-import tuf.exceptions
-import tuf.formats
+from tuf import exceptions, formats
 
 # See 'log.py' to learn how logging is handled in TUF.
 logger = logging.getLogger(__name__)
@@ -65,7 +63,7 @@ def download_file(url, required_length, fetcher, strict_required_length=True):
       A file object is created on disk to store the contents of 'url'.
 
     <Exceptions>
-      tuf.exceptions.DownloadLengthMismatchError, if there was a
+      exceptions.DownloadLengthMismatchError, if there was a
       mismatch of observed vs expected lengths while downloading the file.
 
       securesystemslib.exceptions.FormatError, if any of the arguments are
@@ -78,8 +76,8 @@ def download_file(url, required_length, fetcher, strict_required_length=True):
     """
     # Do all of the arguments have the appropriate format?
     # Raise 'securesystemslib.exceptions.FormatError' if there is a mismatch.
-    securesystemslib.formats.URL_SCHEMA.check_match(url)
-    tuf.formats.LENGTH_SCHEMA.check_match(required_length)
+    sslib_formats.URL_SCHEMA.check_match(url)
+    formats.LENGTH_SCHEMA.check_match(required_length)
 
     # 'url.replace('\\', '/')' is needed for compatibility with Windows-based
     # systems, because they might use back-slashes in place of forward-slashes.
@@ -185,7 +183,7 @@ def _check_downloaded_length(
       strict_required_length is True and total_downloaded is not equal
       required_length.
 
-      tuf.exceptions.SlowRetrievalError, if the total downloaded was
+      exceptions.SlowRetrievalError, if the total downloaded was
       done in less than the acceptable download speed (as set in
       tuf.settings.py).
 
@@ -223,15 +221,15 @@ def _check_downloaded_length(
             logger.debug(msg)
 
             if average_download_speed < tuf.settings.MIN_AVERAGE_DOWNLOAD_SPEED:
-                raise tuf.exceptions.SlowRetrievalError(average_download_speed)
+                raise exceptions.SlowRetrievalError(average_download_speed)
 
             msg = (
                 f"Good average download speed: "
                 f"{average_download_speed} bytes per second"
             )
             logger.debug(msg)
 
-            raise tuf.exceptions.DownloadLengthMismatchError(
+            raise exceptions.DownloadLengthMismatchError(
                 required_length, total_downloaded
             )
 
@@ -241,7 +239,7 @@ def _check_downloaded_length(
         # signed metadata; so, we must guess a reasonable required_length
         # for it.
         if average_download_speed < tuf.settings.MIN_AVERAGE_DOWNLOAD_SPEED:
-            raise tuf.exceptions.SlowRetrievalError(average_download_speed)
+            raise exceptions.SlowRetrievalError(average_download_speed)
 
         msg = (
             f"Good average download speed: "

tuf/client_rework/metadata_wrapper.py

@@ -9,7 +9,7 @@
 
 from securesystemslib.keys import format_metadata_to_key
 
-import tuf.exceptions
+from tuf import exceptions, formats
 from tuf.api import metadata
 
 
@@ -64,7 +64,7 @@ def verify(self, keys, threshold):
             verified += 1
 
         if verified < threshold:
-            raise tuf.exceptions.InsufficientKeysError
+            raise exceptions.InsufficientKeysError
 
     def persist(self, filename):
         """
@@ -77,13 +77,13 @@ def expires(self, reference_time=None):
         TODO
         """
         if reference_time is None:
-            expires_timestamp = tuf.formats.datetime_to_unix_timestamp(
+            expires_timestamp = formats.datetime_to_unix_timestamp(
                 self._meta.signed.expires
             )
             reference_time = int(time.time())
 
         if expires_timestamp < reference_time:
-            raise tuf.exceptions.ExpiredMetadataError
+            raise exceptions.ExpiredMetadataError
 
 
 class RootWrapper(MetadataWrapper):

tuf/client_rework/mirrors.py

@@ -26,11 +26,12 @@
 import urllib
 from typing import BinaryIO, Dict, TextIO
 
-import securesystemslib
+from securesystemslib import exceptions as sslib_exceptions
+from securesystemslib import formats as sslib_formats
+from securesystemslib import util as sslib_util
 
-import tuf
-import tuf.client_rework.download as download
-import tuf.formats
+from tuf import exceptions, formats
+from tuf.client_rework import download
 
 # The type of file to be downloaded from a repository.  The
 # 'get_list_of_mirrors' function supports these file types.
@@ -78,13 +79,13 @@ def get_list_of_mirrors(file_type, file_path, mirrors_dict):
     """
 
     # Checking if all the arguments have appropriate format.
-    tuf.formats.RELPATH_SCHEMA.check_match(file_path)
-    tuf.formats.MIRRORDICT_SCHEMA.check_match(mirrors_dict)
-    securesystemslib.formats.NAME_SCHEMA.check_match(file_type)
+    formats.RELPATH_SCHEMA.check_match(file_path)
+    formats.MIRRORDICT_SCHEMA.check_match(mirrors_dict)
+    sslib_formats.NAME_SCHEMA.check_match(file_type)
 
     # Verify 'file_type' is supported.
     if file_type not in _SUPPORTED_FILE_TYPES:
-        raise securesystemslib.exceptions.Error(
+        raise sslib_exceptions.Error(
             "Invalid file_type argument."
             "  Supported file types: " + repr(_SUPPORTED_FILE_TYPES)
         )
@@ -96,7 +97,7 @@ def get_list_of_mirrors(file_type, file_path, mirrors_dict):
     # on a repository mirror when fetching target files.  This field may be set
     # by the client when the repository mirror is added to the
     # 'tuf.client.updater.Updater' object.
-    in_confined_directory = securesystemslib.util.file_in_confined_directories
+    in_confined_directory = sslib_util.file_in_confined_directories
 
     list_of_mirrors = []
     for dummy, mirror_info in mirrors_dict.items():
@@ -160,7 +161,7 @@ def mirror_meta_download(
 
         finally:
             if file_mirror_errors:
-                raise tuf.exceptions.NoWorkingMirrorError(file_mirror_errors)
+                raise exceptions.NoWorkingMirrorError(file_mirror_errors)
 
 
 def mirror_target_download(
@@ -192,4 +193,4 @@ def mirror_target_download(
 
         finally:
             if file_mirror_errors:
-                raise tuf.exceptions.NoWorkingMirrorError(file_mirror_errors)
+                raise exceptions.NoWorkingMirrorError(file_mirror_errors)

tuf/client_rework/requests_fetcher.py

@@ -13,8 +13,8 @@
 import requests
 import urllib3.exceptions
 
-import tuf.exceptions
-import tuf.settings
+import tuf
+from tuf import exceptions, settings
 from tuf.client_rework.fetcher import FetcherInterface
 
 # Globals
@@ -58,9 +58,9 @@ def fetch(self, url, required_length):
                 bytes.
 
         Raises:
-            tuf.exceptions.SlowRetrievalError: A timeout occurs while receiving
+            exceptions.SlowRetrievalError: A timeout occurs while receiving
                 data.
-            tuf.exceptions.FetcherHTTPError: An HTTP error code is received.
+            exceptions.FetcherHTTPError: An HTTP error code is received.
 
         Returns:
             A bytes iterator
@@ -76,15 +76,15 @@ def fetch(self, url, required_length):
         #  - connect timeout (max delay before first byte is received)
         #  - read (gap) timeout (max delay between bytes received)
         response = session.get(
-            url, stream=True, timeout=tuf.settings.SOCKET_TIMEOUT
+            url, stream=True, timeout=settings.SOCKET_TIMEOUT
         )
         # Check response status.
         try:
             response.raise_for_status()
         except requests.HTTPError as e:
             response.close()
             status = e.response.status_code
-            raise tuf.exceptions.FetcherHTTPError(str(e), status)
+            raise exceptions.FetcherHTTPError(str(e), status)
 
         # Define a generator function to be returned by fetch. This way the
         # caller of fetch can differentiate between connection and actual data
@@ -99,11 +99,11 @@ def chunks():
                     # large file in one shot. Before beginning the round, sleep
                     # (if set) for a short amount of time so that the CPU is not
                     # hogged in the while loop.
-                    if tuf.settings.SLEEP_BEFORE_ROUND:
-                        time.sleep(tuf.settings.SLEEP_BEFORE_ROUND)
+                    if settings.SLEEP_BEFORE_ROUND:
+                        time.sleep(settings.SLEEP_BEFORE_ROUND)
 
                     read_amount = min(
-                        tuf.settings.CHUNK_SIZE,
+                        settings.CHUNK_SIZE,
                         required_length - bytes_received,
                     )
 
@@ -131,7 +131,7 @@ def chunks():
                         break
 
             except urllib3.exceptions.ReadTimeoutError as e:
-                raise tuf.exceptions.SlowRetrievalError(str(e))
+                raise exceptions.SlowRetrievalError(str(e))
 
             finally:
                 response.close()
@@ -147,7 +147,7 @@ def _get_session(self, url):
         parsed_url = urllib.parse.urlparse(url)
 
         if not parsed_url.scheme or not parsed_url.hostname:
-            raise tuf.exceptions.URLParsingError(
+            raise exceptions.URLParsingError(
                 "Could not get scheme and hostname from URL: " + url
             )
 

tuf/client_rework/updater_rework.py

@@ -18,7 +18,7 @@
 
 from tuf import exceptions, settings
 from tuf.client.fetcher import FetcherInterface
-from tuf.client_rework import download, mirrors, requests_fetcher
+from tuf.client_rework import mirrors, requests_fetcher
 
 from .metadata_wrapper import (
     RootWrapper,