[v2] Add Session IDs to User-Agent header even when cache does not exist

.changes/next-release/bugfix-UserAgent-47668.json

@@ -0,0 +1,5 @@
+{
+  "type": "bugfix",
+  "category": "User Agent",
+  "description": "Ensure that session IDs are added to the User-Agent HTTP header even when the local AWS CLI cache does not exist."
+}

awscli/telemetry.py

@@ -76,13 +76,14 @@ class CLISessionDatabaseConnection:
     """
     _ENABLE_WAL = 'PRAGMA journal_mode=WAL'
 
-    def __init__(self, connection=None):
+    def __init__(self, connection=None, cache_dir=None):
+        self._cache_dir = cache_dir or _CACHE_DIR
+        self._ensure_cache_dir()
         self._connection = connection or sqlite3.connect(
-            _CACHE_DIR / _DATABASE_FILENAME,
+            self._cache_dir / _DATABASE_FILENAME,
             check_same_thread=False,
             isolation_level=None,
         )
-        self._ensure_cache_dir()
         self._ensure_database_setup()
 
     def execute(self, query, *parameters):
@@ -95,7 +96,7 @@ def execute(self, query, *parameters):
             return sqlite3.Cursor(self._connection)
 
     def _ensure_cache_dir(self):
-        _CACHE_DIR.mkdir(parents=True, exist_ok=True)
+        self._cache_dir.mkdir(parents=True, exist_ok=True)
 
     def _ensure_database_setup(self):
         self._create_session_table()

tests/functional/test_telemetry.py

@@ -107,6 +107,20 @@ def test_ensure_database_setup(self, session_conn):
         )
         assert cursor.fetchall() == [('session',), ('host_id',)]
 
+    def test_creates_database_when_cache_dir_does_not_exist(self, tmp_path):
+        # When the cache directory doesn't exist, the connection should still
+        # be established successfully.
+        nonexistent_dir = tmp_path / 'nonexistent' / 'nested' / 'cache'
+        assert not nonexistent_dir.exists()
+        conn = CLISessionDatabaseConnection(cache_dir=nonexistent_dir)
+        assert nonexistent_dir.exists()
+        assert (nonexistent_dir / 'session.db').exists()
+        # Verify the database is functional.
+        writer = CLISessionDatabaseWriter(conn)
+        reader = CLISessionDatabaseReader(conn)
+        writer.write(CLISessionData('key', 'sid', 1000000000))
+        assert reader.read('key').session_id == 'sid'
+
     def test_timeout_does_not_raise_exception(self, session_conn):
         test_query = """
             SELECT name

tests/integration/test_cli.py

@@ -310,15 +310,6 @@ def test_version(self):
         )
         self.assertTrue(re.fullmatch(user_agent_regex, version_output))
 
-    def test_version_does_not_create_cache_directory(self):
-        # Regression test: --version should not create any files/directories.
-        with tempfile.TemporaryDirectory() as tmpdir:
-            env = os.environ.copy()
-            env['HOME'] = tmpdir
-            aws('--version', env_vars=env)
-            aws_dir = os.path.join(tmpdir, '.aws')
-            self.assertFalse(os.path.exists(aws_dir))
-
     def test_version_with_exec_env(self):
         base_env_vars = os.environ.copy()
         base_env_vars['AWS_EXECUTION_ENV'] = 'an_execution_env'