[client rework]: Add tests and linter config

Adds a basic test case for Updater.
Applies to client_rework the linter config used in api/metadata.py

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

tests/test_updater_rework.py

@@ -0,0 +1,248 @@
+#!/usr/bin/env python
+
+# Copyright 2021, New York University and the TUF contributors
+# SPDX-License-Identifier: MIT OR Apache-2.0
+
+"""Test Updater class
+"""
+
+import os
+import time
+import shutil
+import copy
+import tempfile
+import logging
+import errno
+import sys
+import unittest
+import json
+import tracemalloc
+
+if sys.version_info >= (3, 3):
+  import unittest.mock as mock
+else:
+  import mock
+
+import tuf
+import tuf.exceptions
+import tuf.log
+import tuf.repository_tool as repo_tool
+import tuf.unittest_toolbox as unittest_toolbox
+import tuf.client_rework.updater_rework as updater
+
+from tests import utils
+from tuf.api import metadata
+
+import securesystemslib
+
+logger = logging.getLogger(__name__)
+
+
+class TestUpdater(unittest_toolbox.Modified_TestCase):
+
+  @classmethod
+  def setUpClass(cls):
+    # Create a temporary directory to store the repository, metadata, and target
+    # files.  'temporary_directory' must be deleted in TearDownModule() so that
+    # temporary files are always removed, even when exceptions occur.
+    cls.temporary_directory = tempfile.mkdtemp(dir=os.getcwd())
+
+    # Needed because in some tests simple_server.py cannot be found.
+    # The reason is that the current working directory
+    # has been changed when executing a subprocess.
+    cls.SIMPLE_SERVER_PATH = os.path.join(os.getcwd(), 'simple_server.py')
+
+    # Launch a SimpleHTTPServer (serves files in the current directory).
+    # Test cases will request metadata and target files that have been
+    # pre-generated in 'tuf/tests/repository_data', which will be served
+    # by the SimpleHTTPServer launched here.  The test cases of 'test_updater.py'
+    # assume the pre-generated metadata files have a specific structure, such
+    # as a delegated role 'targets/role1', three target files, five key files,
+    # etc.
+    cls.server_process_handler = utils.TestServerProcess(log=logger,
+        server=cls.SIMPLE_SERVER_PATH)
+
+
+
+  @classmethod
+  def tearDownClass(cls):
+    # Cleans the resources and flush the logged lines (if any).
+    cls.server_process_handler.clean()
+
+    # Remove the temporary repository directory, which should contain all the
+    # metadata, targets, and key files generated for the test cases
+    shutil.rmtree(cls.temporary_directory)
+
+
+
+  def setUp(self):
+    # We are inheriting from custom class.
+    unittest_toolbox.Modified_TestCase.setUp(self)
+
+    self.repository_name = 'test_repository1'
+
+    # Copy the original repository files provided in the test folder so that
+    # any modifications made to repository files are restricted to the copies.
+    # The 'repository_data' directory is expected to exist in 'tuf.tests/'.
+    original_repository_files = os.path.join(os.getcwd(), 'repository_data')
+    temporary_repository_root = \
+      self.make_temp_directory(directory=self.temporary_directory)
+
+    # The original repository, keystore, and client directories will be copied
+    # for each test case.
+    original_repository = os.path.join(original_repository_files, 'repository')
+    original_keystore = os.path.join(original_repository_files, 'keystore')
+    original_client = os.path.join(original_repository_files, 'client')
+
+    # Save references to the often-needed client repository directories.
+    # Test cases need these references to access metadata and target files.
+    self.repository_directory = \
+      os.path.join(temporary_repository_root, 'repository')
+    self.keystore_directory = \
+      os.path.join(temporary_repository_root, 'keystore')
+
+    self.client_directory = os.path.join(temporary_repository_root,
+        'client')
+    self.client_metadata = os.path.join(self.client_directory,
+        self.repository_name, 'metadata')
+    self.client_metadata_current = os.path.join(self.client_metadata,
+        'current')
+
+    # Copy the original 'repository', 'client', and 'keystore' directories
+    # to the temporary repository the test cases can use.
+    shutil.copytree(original_repository, self.repository_directory)
+    shutil.copytree(original_client, self.client_directory)
+    shutil.copytree(original_keystore, self.keystore_directory)
+
+    # 'path/to/tmp/repository' -> 'localhost:8001/tmp/repository'.
+    repository_basepath = self.repository_directory[len(os.getcwd()):]
+    url_prefix = 'http://' + utils.TEST_HOST_ADDRESS + ':' \
+        + str(self.server_process_handler.port) + repository_basepath
+
+    # Setting 'tuf.settings.repository_directory' with the temporary client
+    # directory copied from the original repository files.
+    tuf.settings.repositories_directory = self.client_directory
+
+    self.repository_mirrors = {'mirror1': {'url_prefix': url_prefix,
+                                           'metadata_path': 'metadata',
+                                           'targets_path': 'targets'}}
+
+    # Creating a repository instance.  The test cases will use this client
+    # updater to refresh metadata, fetch target files, etc.
+    self.repository_updater = updater.Updater(self.repository_name,
+                                              self.repository_mirrors)
+
+    # Metadata role keys are needed by the test cases to make changes to the
+    # repository (e.g., adding a new target file to 'targets.json' and then
+    # requesting a refresh()).
+    self.role_keys = _load_role_keys(self.keystore_directory)
+
+
+
+  def tearDown(self):
+    # We are inheriting from custom class.
+    unittest_toolbox.Modified_TestCase.tearDown(self)
+
+    # Logs stdout and stderr from the sever subprocess.
+    self.server_process_handler.flush_log()
+
+
+
+  # UNIT TESTS.
+  def test_refresh(self):
+
+    self.repository_updater.refresh()
+
+    for role in ['root', 'timestamp', 'snapshot', 'targets']:
+        metadata_obj = metadata.Metadata.from_file(os.path.join(
+            self.client_metadata_current, role + '.json'))
+
+        metadata_obj_2 = metadata.Metadata.from_file(os.path.join(
+            self.repository_directory, 'metadata', role + '.json'))
+
+
+        self.assertDictEqual(metadata_obj.to_dict(),
+                             metadata_obj_2.to_dict())
+
+    # Get targetinfo for 'file1.txt' listed in targets
+    targetinfo1 = self.repository_updater.get_one_valid_targetinfo('file1.txt')
+    # Get targetinfo for 'file3.txt' listed in the delegated role1
+    targetinfo3= self.repository_updater.get_one_valid_targetinfo('file3.txt')
+
+    destination_directory = self.make_temp_directory()
+    updated_targets = self.repository_updater.updated_targets([targetinfo1, targetinfo3],
+                                                      destination_directory)
+
+    self.assertListEqual(updated_targets, [targetinfo1, targetinfo3])
+
+    self.repository_updater.download_target(targetinfo1, destination_directory)
+    updated_targets = self.repository_updater.updated_targets(updated_targets,
+                                                      destination_directory)
+
+    self.assertListEqual(updated_targets, [targetinfo3])
+
+
+    self.repository_updater.download_target(targetinfo3, destination_directory)
+    updated_targets = self.repository_updater.updated_targets(updated_targets,
+                                                  destination_directory)
+
+    self.assertListEqual(updated_targets, [])
+
+
+def _load_role_keys(keystore_directory):
+
+  # Populating 'self.role_keys' by importing the required public and private
+  # keys of 'tuf/tests/repository_data/'.  The role keys are needed when
+  # modifying the remote repository used by the test cases in this unit test.
+
+  # The pre-generated key files in 'repository_data/keystore' are all encrypted with
+  # a 'password' passphrase.
+  EXPECTED_KEYFILE_PASSWORD = 'password'
+
+  # Store and return the cryptography keys of the top-level roles, including 1
+  # delegated role.
+  role_keys = {}
+
+  root_key_file = os.path.join(keystore_directory, 'root_key')
+  targets_key_file = os.path.join(keystore_directory, 'targets_key')
+  snapshot_key_file = os.path.join(keystore_directory, 'snapshot_key')
+  timestamp_key_file = os.path.join(keystore_directory, 'timestamp_key')
+  delegation_key_file = os.path.join(keystore_directory, 'delegation_key')
+
+  role_keys = {'root': {}, 'targets': {}, 'snapshot': {}, 'timestamp': {},
+               'role1': {}}
+
+  # Import the top-level and delegated role public keys.
+  role_keys['root']['public'] = \
+    repo_tool.import_rsa_publickey_from_file(root_key_file+'.pub')
+  role_keys['targets']['public'] = \
+    repo_tool.import_ed25519_publickey_from_file(targets_key_file+'.pub')
+  role_keys['snapshot']['public'] = \
+    repo_tool.import_ed25519_publickey_from_file(snapshot_key_file+'.pub')
+  role_keys['timestamp']['public'] = \
+      repo_tool.import_ed25519_publickey_from_file(timestamp_key_file+'.pub')
+  role_keys['role1']['public'] = \
+      repo_tool.import_ed25519_publickey_from_file(delegation_key_file+'.pub')
+
+  # Import the private keys of the top-level and delegated roles.
+  role_keys['root']['private'] = \
+    repo_tool.import_rsa_privatekey_from_file(root_key_file,
+                                              EXPECTED_KEYFILE_PASSWORD)
+  role_keys['targets']['private'] = \
+    repo_tool.import_ed25519_privatekey_from_file(targets_key_file,
+                                              EXPECTED_KEYFILE_PASSWORD)
+  role_keys['snapshot']['private'] = \
+    repo_tool.import_ed25519_privatekey_from_file(snapshot_key_file,
+                                              EXPECTED_KEYFILE_PASSWORD)
+  role_keys['timestamp']['private'] = \
+    repo_tool.import_ed25519_privatekey_from_file(timestamp_key_file,
+                                              EXPECTED_KEYFILE_PASSWORD)
+  role_keys['role1']['private'] = \
+    repo_tool.import_ed25519_privatekey_from_file(delegation_key_file,
+                                              EXPECTED_KEYFILE_PASSWORD)
+
+  return role_keys
+
+if __name__ == '__main__':
+  utils.configure_test_logging(sys.argv)
+  unittest.main()

tox.ini

@@ -48,3 +48,8 @@ commands =
     pylint {toxinidir}/tuf --ignore={toxinidir}/tuf/api,{toxinidir}/tuf/api/serialization
     pylint {toxinidir}/tuf/api --rcfile={toxinidir}/tuf/api/pylintrc
     bandit -r {toxinidir}/tuf
+
+[testenv:lint-client]
+commands =
+    pylint {toxinidir}/tuf/client_rework --rcfile={toxinidir}/tuf/client_rework/pylintrc
+    bandit -r {toxinidir}/tuf

tuf/client_rework/pylintrc

@@ -0,0 +1,6 @@
+[MESSAGE_CONTROL]
+disable=fixme
+
+[FORMAT]
+indent-string="    "
+max-line-length=79