logging: Eliminate log_level from create_logger.

Because calls to `create_logger` generally run after settings are
configured, these would override what we have in `settings.LOGGING` --
which in particular defeated any attempt to set log levels in
`test_settings.py`.  Move all of these settings to the same place in
`settings.py`, so they can be overridden in a uniform way.

zerver/decorator.py

@@ -46,8 +46,7 @@ ViewFuncT = TypeVar('ViewFuncT', bound=Callable[..., HttpResponse])
 ReturnT = TypeVar('ReturnT')
 
 ## logger setup
-webhook_logger = create_logger(
-    "zulip.zerver.webhooks", settings.API_KEY_ONLY_WEBHOOK_LOG_PATH, 'DEBUG')
+webhook_logger = create_logger("zulip.zerver.webhooks", settings.API_KEY_ONLY_WEBHOOK_LOG_PATH)
 
 class _RespondAsynchronously:
     pass

zerver/lib/digest.py

@@ -19,7 +19,7 @@ from zerver.context_processors import common_context
 from zerver.lib.queue import queue_json_publish
 from zerver.lib.logging_util import create_logger
 
-logger = create_logger(__name__, settings.DIGEST_LOG_PATH, 'DEBUG')
+logger = create_logger(__name__, settings.DIGEST_LOG_PATH)
 
 VALID_DIGEST_DAY = 1  # Tuesdays
 DIGEST_CUTOFF = 5

zerver/lib/logging_util.py

@@ -187,7 +187,6 @@ class ZulipFormatter(logging.Formatter):
 
 def create_logger(name: str,
                   log_file: str,
-                  log_level: Optional[str]=None,
                   log_format: str="%(asctime)s%(levelname)-8s%(message)s") -> Logger:
     """Creates a named logger for use in logging content to a certain
     file.  A few notes:
@@ -201,9 +200,6 @@ def create_logger(name: str,
     logging.basicConfig(format=log_format)
     logger = logging.getLogger(name)
 
-    if log_level is not None:
-        logger.setLevel(getattr(logging, log_level))
-
     if log_file:
         formatter = logging.Formatter(log_format)
         file_handler = logging.FileHandler(log_file)

zerver/management/commands/deliver_email.py

@@ -24,7 +24,7 @@ from zerver.lib.send_email import EmailNotDeliveredException, send_email
 from zerver.models import ScheduledEmail
 
 ## Setup ##
-logger = create_logger(__name__, settings.EMAIL_DELIVERER_LOG_PATH, 'DEBUG')
+logger = create_logger(__name__, settings.EMAIL_DELIVERER_LOG_PATH)
 
 class Command(BaseCommand):
     help = """Deliver emails queued by various parts of Zulip

zerver/management/commands/enqueue_digest_emails.py

@@ -9,7 +9,7 @@ from zerver.lib.digest import DIGEST_CUTOFF, enqueue_emails
 from zerver.lib.logging_util import create_logger
 
 ## Logging setup ##
-logger = create_logger(__name__, settings.DIGEST_LOG_PATH, 'DEBUG')
+logger = create_logger(__name__, settings.DIGEST_LOG_PATH)
 
 class Command(BaseCommand):
     help = """Enqueue digest emails for users that haven't checked the app

zproject/settings.py

@@ -1389,6 +1389,15 @@ LOGGING = {
         },
 
         # our own loggers, alphabetized
+        'zerver.lib.digest': {
+            'level': 'DEBUG',
+        },
+        'zerver.management.commands.deliver_email': {
+            'level': 'DEBUG',
+        },
+        'zerver.management.commands.enqueue_digest_emails': {
+            'level': 'DEBUG',
+        },
         'zulip.management': {
             'handlers': ['file', 'errors_file'],
             'propagate': False,
@@ -1401,6 +1410,7 @@ LOGGING = {
             'propagate': False,
         },
         'zulip.zerver.webhooks': {
+            'level': 'DEBUG',
             'handlers': ['file', 'errors_file'],
             'propagate': False,
         },