Merged PR 6457: SYNC: GH to ADO Main

#### AI description  (iteration 1)
#### PR Classification
This pull request is a code migration and cleanup effort that overhauls the logging framework across the repository.

#### PR Summary
The changes replace the legacy logging system (including the removed `logging_config.py`) with a new, unified logging module and logger bridge for both Python and C++ code, improving performance, consistency, and coverage reporting.
- **`mssql_python/logging.py`**: Introduces a new logger module that defines logger APIs (debug/info/warning/error) and deprecates the old logging configuration.
- **`mssql_python/pybind/logger_bridge.cpp` and `.hpp`**: Add a new logger bridge to efficiently propagate C++ log messages to the Python logging system.
- **Core modules (e.g., connection, auth, pooling, cursor) and test files (e.g., tests for logging, performance, and integration)** have been updated to use the new logging API.
- Several obsolete files, including `logging_config.py`, `.config/SDL_CONFIGURATION.md`, and `unix_buffers.h`, were removed to clean up the codebase.
<!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->

Related work items: #40479

Author: bewithgaurav

.config/SDL_CONFIGURATION.md

@@ -6,4 +6,27 @@ omit =
     tests/*
 
 [report]
-# Add any report-specific settings here, if needed
+# Exclude lines that don't need coverage (logging, defensive code, etc.)
+exclude_lines =
+    # Default pragmas
+    pragma: no cover
+    
+    # Don't complain about missing debug-only code
+    def __repr__
+    
+    # Don't complain if tests don't hit defensive assertion code
+    raise AssertionError
+    raise NotImplementedError
+    
+    # Don't complain if non-runnable code isn't run
+    if __name__ == .__main__.:
+    
+    # Exclude all logging statements (zero overhead when disabled by design)
+    logger\.debug
+    logger\.info
+    logger\.warning
+    logger\.error
+    LOG\(
+    
+    # Don't complain about abstract methods
+    @abstract

.coveragerc

@@ -60,3 +60,6 @@ build/
 # Virtual environments
 *venv*/
 **/*venv*/
+
+# learning files
+learnings/

.gitignore

@@ -35,9 +35,11 @@
 
 # Ensure pyodbc connection string has ODBC driver specified
 if CONN_STR and 'Driver=' not in CONN_STR:
-    CONN_STR = f"Driver={{ODBC Driver 18 for SQL Server}};{CONN_STR}"
+    CONN_STR_PYODBC = f"Driver={{ODBC Driver 18 for SQL Server}};{CONN_STR}"
+else:
+    CONN_STR_PYODBC = CONN_STR
 
-NUM_ITERATIONS = 5  # Number of times to run each test for averaging
+NUM_ITERATIONS = 10  # Number of times to run each test for averaging
 
 # SQL Queries
 COMPLEX_JOIN_AGGREGATION = """
@@ -187,7 +189,7 @@ def run_benchmark_pyodbc(query: str, name: str, iterations: int) -> BenchmarkRes
     for i in range(iterations):
         try:
             start_time = time.time()
-            conn = pyodbc.connect(CONN_STR)
+            conn = pyodbc.connect(CONN_STR_PYODBC)
             cursor = conn.cursor()
             cursor.execute(query)
             rows = cursor.fetchall()

benchmarks/perf-benchmarking.py

@@ -81,11 +81,17 @@ llvm-cov export "$PYBIND_SO" \
   --skip-functions \
   -format=lcov > cpp-coverage.info
 
+# Note: LCOV exclusion markers (LCOV_EXCL_LINE) should be added to source code
+# to exclude LOG() statements from coverage. However, for automated exclusion
+# of all LOG lines without modifying source code, we can use geninfo's --omit-lines
+# feature during the merge step (see below).
+
 echo "==================================="
 echo "[STEP 4] Merging Python + C++ coverage"
 echo "==================================="
 
 # Merge LCOV reports (ignore inconsistencies in Python LCOV export)
+echo "[ACTION] Merging Python and C++ coverage"
 lcov -a python-coverage.info -a cpp-coverage.info -o total.info \
   --ignore-errors inconsistent,corrupt
 

generate_codecov.sh

@@ -1,15 +1,12 @@
 from mssql_python import connect
-from mssql_python import setup_logging
+from mssql_python.logging import setup_logging
 import os
-import decimal
 
-setup_logging('stdout')
+# Clean one-liner: set level and output mode together
+setup_logging(output="both")
 
 conn_str = os.getenv("DB_CONNECTION_STRING")
 conn = connect(conn_str)
-
-# conn.autocommit = True
-
 cursor = conn.cursor()
 cursor.execute("SELECT database_id, name from sys.databases;")
 rows = cursor.fetchall()

main.py

@@ -54,8 +54,8 @@
 # Cursor Objects
 from .cursor import Cursor
 
-# Logging Configuration
-from .logging_config import setup_logging, get_logger
+# Logging Configuration (Simplified single-level DEBUG system)
+from .logging import logger, setup_logging, driver_logger
 
 # Constants
 from .constants import ConstantsDDBC, GetInfoConstants
@@ -182,6 +182,19 @@ def pooling(max_size: int = 100, idle_timeout: int = 600, enabled: bool = True)
 
 _original_module_setattr = sys.modules[__name__].__setattr__
 
+def _custom_setattr(name, value):
+    if name == 'lowercase':
+        with _settings_lock:
+            _settings.lowercase = bool(value)
+            # Update the module's lowercase variable
+            _original_module_setattr(name, _settings.lowercase)
+    else:
+        _original_module_setattr(name, value)
+
+# Replace the module's __setattr__ with our custom version
+sys.modules[__name__].__setattr__ = _custom_setattr
+
+
 # Export SQL constants at module level
 SQL_VARCHAR: int = ConstantsDDBC.SQL_VARCHAR.value
 SQL_LONGVARCHAR: int = ConstantsDDBC.SQL_LONGVARCHAR.value