chore: use os.path.join instead of concatenating paths

Removes trailing and connection slashes from paths, and everything reads
more pythonic

Fixes: #2799

Signed-off-by: Renan Rodrigo <[email protected]>

uaclient/defaults.py

@@ -5,35 +5,54 @@
 any of our dependencies installed.
 """
 
-UAC_ETC_PATH = "/etc/ubuntu-advantage/"
-UAC_RUN_PATH = "/run/ubuntu-advantage/"
+import os
+
+# Base directories
+UAC_ETC_PATH = "/etc/ubuntu-advantage"
+UAC_RUN_PATH = "/run/ubuntu-advantage"
 DEFAULT_DATA_DIR = "/var/lib/ubuntu-advantage"
+DEFAULT_LOG_DIR = "/var/log"
+
+
+# Relative paths
 MACHINE_TOKEN_FILE = "machine-token.json"
+CONFIG_FILE = "uaclient.conf"
+USER_CONFIG_FILE = "user-config.json"
+CANDIDATE_VERSION_FILE = "candidate-version"
+DEFAULT_LOG_FILE_BASE_NAME = "ubuntu-advantage"
 PRIVATE_SUBDIR = "private"
-DEFAULT_PRIVATE_MACHINE_TOKEN_PATH = (
-    DEFAULT_DATA_DIR + "/" + PRIVATE_SUBDIR + "/" + MACHINE_TOKEN_FILE
+MESSAGES_SUBDIR = "messages"
+USER_CACHE_SUBDIR = "ubuntu-pro"
+NOTICES_SUBDIR = "notices"
+PRIVATE_ESM_CACHE_SUBDIR = "apt-esm"
+
+DEFAULT_PRIVATE_MACHINE_TOKEN_PATH = os.path.join(
+    DEFAULT_DATA_DIR, PRIVATE_SUBDIR, MACHINE_TOKEN_FILE
+)
+DEFAULT_PRIVATE_DATA_DIR = os.path.join(DEFAULT_DATA_DIR, PRIVATE_SUBDIR)
+MESSAGES_DIR = os.path.join(DEFAULT_DATA_DIR, MESSAGES_SUBDIR)
+DEFAULT_CONFIG_FILE = os.path.join(UAC_ETC_PATH, CONFIG_FILE)
+CANDIDATE_CACHE_PATH = os.path.join(UAC_RUN_PATH, CANDIDATE_VERSION_FILE)
+DEFAULT_USER_CONFIG_JSON_FILE = os.path.join(
+    DEFAULT_DATA_DIR, USER_CONFIG_FILE
 )
-DEFAULT_PRIVATE_DATA_DIR = DEFAULT_DATA_DIR + "/" + PRIVATE_SUBDIR
-MESSAGES_SUBDIR = "/messages"
-MESSAGES_DIR = DEFAULT_DATA_DIR + MESSAGES_SUBDIR
-CANDIDATE_CACHE_PATH = UAC_RUN_PATH + "candidate-version"
-DEFAULT_CONFIG_FILE = UAC_ETC_PATH + "uaclient.conf"
-DEFAULT_USER_CONFIG_JSON_FILE = DEFAULT_DATA_DIR + "/user-config.json"
-DEFAULT_UPGRADE_CONTRACT_FLAG_FILE = UAC_ETC_PATH + "request-update-contract"
+DEFAULT_LOG_PREFIX = os.path.join(DEFAULT_LOG_DIR, DEFAULT_LOG_FILE_BASE_NAME)
+ESM_APT_ROOTDIR = os.path.join(DEFAULT_DATA_DIR, PRIVATE_ESM_CACHE_SUBDIR)
+NOTICES_PERMANENT_DIRECTORY = os.path.join(DEFAULT_DATA_DIR, NOTICES_SUBDIR)
+NOTICES_TEMPORARY_DIRECTORY = os.path.join(UAC_RUN_PATH, NOTICES_SUBDIR)
+
+
+# URLs
 BASE_CONTRACT_URL = "https://contracts.canonical.com"
 BASE_SECURITY_URL = "https://ubuntu.com/security"
 BASE_LIVEPATCH_URL = "https://livepatch.canonical.com"
 APT_NEWS_URL = "https://motd.ubuntu.com/aptnews.json"
-CLOUD_BUILD_INFO = "/etc/cloud/build.info"
-ESM_APT_ROOTDIR = DEFAULT_DATA_DIR + "/apt-esm/"
 
 PRINT_WRAP_WIDTH = 80
 CONTRACT_EXPIRY_GRACE_PERIOD_DAYS = 14
 CONTRACT_EXPIRY_PENDING_DAYS = 20
 ATTACH_FAIL_DATE_FORMAT = "%B %d, %Y"
-DEFAULT_LOG_DIR = "/var/log"
-DEFAULT_LOG_FILE_BASE_NAME = "ubuntu-advantage"
-DEFAULT_LOG_PREFIX = DEFAULT_LOG_DIR + "/" + DEFAULT_LOG_FILE_BASE_NAME
+
 DEFAULT_LOG_FORMAT = (
     "%(asctime)s - %(filename)s:(%(lineno)d) [%(levelname)s]: %(message)s"
 )
@@ -43,7 +62,7 @@
     "security_url": BASE_SECURITY_URL,
     "data_dir": DEFAULT_DATA_DIR,
     "log_level": "debug",
-    "log_file": "/var/log/ubuntu-advantage.log",
+    "log_file": "{}.log".format(DEFAULT_LOG_PREFIX),
 }
 
 CONFIG_FIELD_ENVVAR_ALLOWLIST = [
@@ -55,10 +74,8 @@
 
 ROOT_READABLE_MODE = 0o600
 WORLD_READABLE_MODE = 0o644
-NOTICES_PERMANENT_DIRECTORY = DEFAULT_DATA_DIR + "/notices/"
-NOTICES_TEMPORARY_DIRECTORY = UAC_RUN_PATH + "notices/"
-USER_CACHE_SUBDIR = "ubuntu-pro"
 
+CLOUD_BUILD_INFO = "/etc/cloud/build.info"
 SSL_CERTS_PATH = "/etc/ssl/certs/ca-certificates.crt"
 
 # used by apport, collect-logs, and tests

uaclient/files/files.py

@@ -79,7 +79,7 @@ def __init__(
     ):
         file_name = defaults.MACHINE_TOKEN_FILE
         self.private_file = UAFile(
-            file_name, directory + "/" + defaults.PRIVATE_SUBDIR
+            file_name, os.path.join(directory, defaults.PRIVATE_SUBDIR)
         )
         self.public_file = UAFile(file_name, directory, False)
         self.machine_token_overlay_path = machine_token_overlay_path

uaclient/log.py

@@ -63,7 +63,7 @@ def format(self, record: logging.LogRecord) -> str:
 
 def get_user_log_file() -> str:
     """Gets the correct user log_file storage location"""
-    return system.get_user_cache_dir() + "/ubuntu-pro.log"
+    return os.path.join(system.get_user_cache_dir(), "ubuntu-pro.log")
 
 
 def get_all_user_log_files() -> List[str]:
@@ -74,12 +74,12 @@ def get_all_user_log_files() -> List[str]:
     user_directories = os.listdir("/home")
     log_files = []
     for user_directory in user_directories:
-        user_path = (
-            "/home/"
-            + user_directory
-            + "/.cache/"
-            + defaults.USER_CACHE_SUBDIR
-            + "/ubuntu-pro.log"
+        user_path = os.path.join(
+            "/home",
+            user_directory,
+            ".cache",
+            defaults.USER_CACHE_SUBDIR,
+            "ubuntu-pro.log",
         )
         if os.path.isfile(user_path):
             log_files.append(user_path)

uaclient/system.py

@@ -753,9 +753,11 @@ def get_user_cache_dir() -> str:
 
     xdg_cache_home = os.environ.get("XDG_CACHE_HOME")
     if xdg_cache_home:
-        return xdg_cache_home + "/" + defaults.USER_CACHE_SUBDIR
+        return os.path.join(xdg_cache_home, defaults.USER_CACHE_SUBDIR)
 
-    return os.path.expanduser("~") + "/.cache/" + defaults.USER_CACHE_SUBDIR
+    return os.path.join(
+        os.path.expanduser("~"), ".cache", defaults.USER_CACHE_SUBDIR
+    )
 
 
 def get_reboot_required_pkgs() -> Optional[RebootRequiredPkgs]:

uaclient/tests/test_system.py

@@ -1418,7 +1418,7 @@ class TestGetUserCacheDir:
             "expected",
         ],
         (
-            (True, None, None, "/run/ubuntu-advantage/"),
+            (True, None, None, "/run/ubuntu-advantage"),
             (False, None, "/home/user", "/home/user/.cache/ubuntu-pro"),
             (False, "/something", "/home/user", "/something/ubuntu-pro"),
         ),