Update logging in Python to use module-level logger

All logging in Python so far was done with the root logger, resulting
in logs like: `ERROR:Exception calling application:`. With module-level
loggers, the logs will instead include the module in which the
exception is raised: `ERROR:grpc._server:Exception calling application:`

2 files changed, 6 insertions, 3 deletions

diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/grpc_string.pyx.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/grpc_string.pyx.pxi
index 53e06a1596..00a1b23a67 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/grpc_string.pyx.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/grpc_string.pyx.pxi
@@ -14,6 +14,7 @@
 
 import logging
 
+_LOGGER = logging.getLogger(__name__)
 
 # This function will ascii encode unicode string inputs if neccesary.
 # In Python3, unicode strings are the default str type.
@@ -49,5 +50,5 @@ cdef str _decode(bytes bytestring):
         try:
             return bytestring.decode('utf8')
         except UnicodeDecodeError:
-            logging.exception('Invalid encoding on %s', bytestring)
+            _LOGGER.exception('Invalid encoding on %s', bytestring)
             return bytestring.decode('latin1')
diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi
index 707ec742dd..da3dd21244 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/server.pyx.pxi
@@ -18,6 +18,8 @@ import logging
 import time
 import grpc
 
+_LOGGER = logging.getLogger(__name__)
+
 cdef grpc_ssl_certificate_config_reload_status _server_cert_config_fetcher_wrapper(
         void* user_data, grpc_ssl_server_certificate_config **config) with gil:
   # This is a credentials.ServerCertificateConfig
@@ -34,13 +36,13 @@ cdef grpc_ssl_certificate_config_reload_status _server_cert_config_fetcher_wrapp
     try:
       cert_config_wrapper = user_cb()
     except Exception:
-      logging.exception('Error fetching certificate config')
+      _LOGGER.exception('Error fetching certificate config')
       return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_FAIL
     if cert_config_wrapper is None:
       return GRPC_SSL_CERTIFICATE_CONFIG_RELOAD_UNCHANGED
     elif not isinstance(
         cert_config_wrapper, grpc.ServerCertificateConfiguration):
-      logging.error(
+      _LOGGER.error(
           'Error fetching certificate configuration: certificate '
           'configuration must be of type grpc.ServerCertificateConfiguration, '
           'not %s' % type(cert_config_wrapper).__name__)