Introduce karton debug

.gitignore

@@ -6,3 +6,5 @@ karton.ini
 config.ini
 docs/_build
 .mypy_cache
+build
+karton_core.egg-info/

docs/advanced_concepts.rst

@@ -230,3 +230,19 @@ The simplest way to do that is to perform all of these actions synchronously, in
         # If analysis has been finished: get the results and process them
         analysis = sandbox.get_results(analysis_id)
         self.process_results(analysis)
+
+
+Karton debug mode
+-----------------
+
+During your karton services development endeavours you'll often have the urge to test them out on the production environment.
+
+While this is totally fine, you have to be careful not to disrupt the production services by consuming the tasks meant for them. In most cases you also don't want to propagate logs from your experiments to the production log pipeline.
+
+Karton debug mode was crafted especially for this purpose. It adds a random suffix to the service identity to create a new, non-conflicting task queue.
+It also permanently sets the consumer persistence to False and disables log forwarding.
+
+You can enable it by setting:
+- :code:`KARTON_KARTON_DEBUG` environment value to "1"
+- :code:`debug` parameter to `1` in the :code:`[karton]` config section
+- :code:`--debug` command-line parameter

docs/service_configuration.rst

@@ -48,6 +48,7 @@ Common Karton configuration fields are listed below:
  [redis]        socket_timeout    Socket timeout for Redis operations in seconds (default: 30, use 0 to turn off if timeout doesn't work properly)
  [karton]       identity          Karton service identity override (overrides the name provided in class / constructor arguments)
  [karton]       persistent        Karton service queue persistency override
+ [karton]       debug             Karton debug mode for service development
  [karton]       task_timeout      Karton service task execution timeout in seconds. Useful if your service sometimes hangs. Karton will schedule SIGALRM if this value is set.
  [logging]      level             Logging level for Karton service logger (default: INFO)
  [signaling]    status            Turns on producing of 'karton.signaling.status' tasks, signalling the task start and finish events by Karton service (default: 0, off)
@@ -90,6 +91,7 @@ All settings can be set using command-line.
       --identity IDENTITY   Alternative identity for Karton service
       --log-level LOG_LEVEL
                             Logging level of Karton logger
+      --debug               Enable debugging mode
       --setup-bucket        Create missing bucket in S3 storage
       --disable-gc          Do not run GC in this instance
       --disable-router      Do not run task routing in this instance

karton/core/base.py

@@ -1,6 +1,7 @@
 import abc
 import argparse
 import logging
+import os
 import textwrap
 from contextlib import contextmanager
 from typing import Optional, Union, cast
@@ -44,6 +45,11 @@ def __init__(
         if self.config.has_option("karton", "identity"):
             self.identity = self.config.get("karton", "identity")
 
+        self.debug = self.config.getboolean("karton", "debug", False)
+
+        if self.debug:
+            self.identity += "-" + os.urandom(4).hex() + "-dev"
+
         self.service_info = None
         if self.identity is not None and self.with_service_info:
             self.service_info = KartonServiceInfo(
@@ -101,7 +107,9 @@ def setup_logger(self, level: Optional[Union[str, int]] = None) -> None:
             logging.Formatter("[%(asctime)s][%(levelname)s] %(message)s")
         )
         logger.addHandler(stream_handler)
-        logger.addHandler(self._log_handler)
+
+        if not self.debug:
+            logger.addHandler(self._log_handler)
 
     @property
     def log_handler(self) -> KartonLogHandler:
@@ -154,6 +162,9 @@ def args_parser(cls) -> argparse.ArgumentParser:
             "--identity", help="Alternative identity for Karton service"
         )
         parser.add_argument("--log-level", help="Logging level of Karton logger")
+        parser.add_argument(
+            "--debug", help="Enable debugging mode", action="store_true", default=None
+        )
         return parser
 
     @classmethod
@@ -166,7 +177,10 @@ def config_from_args(cls, config: Config, args: argparse.Namespace) -> None:
         """
         config.load_from_dict(
             {
-                "karton": {"identity": args.identity},
+                "karton": {
+                    "identity": args.identity,
+                    "debug": args.debug,
+                },
                 "logging": {"level": args.log_level},
             }
         )

karton/core/karton.py

@@ -121,8 +121,9 @@ def __init__(
         if self.filters is None:
             raise ValueError("Cannot bind consumer on Empty binds")
 
-        self.persistent = self.config.getboolean(
-            "karton", "persistent", self.persistent
+        self.persistent = (
+            self.config.getboolean("karton", "persistent", self.persistent)
+            and not self.debug
         )
         self.task_timeout = self.config.getint("karton", "task_timeout")
         self.current_task: Optional[Task] = None