chore(MaxMemory): default max_memory via env. variable

docs/source/changelog.rst

@@ -5,6 +5,12 @@ Changelog
 
 All notable changes to this project will be documented in this file.
 
+`0.27.1`_ -- 2020-04-14
+-----------------------
+Added
+^^^^^
+* MaxMemory: pass default max_memory via env. variable (remoulade_max_memory)
+
 `0.27.0`_ -- 2020-04-06
 -----------------------
 Added
@@ -503,6 +509,7 @@ Fixed
 
 * pipe_ignore was not recovered from right message
 
+.. _0.27.1: https://github.com/wiremind/remoulade/releases/tag/v0.27.1
 .. _0.27.0: https://github.com/wiremind/remoulade/releases/tag/v0.27.0
 .. _0.26.7: https://github.com/wiremind/remoulade/releases/tag/v0.26.7
 .. _0.26.6: https://github.com/wiremind/remoulade/releases/tag/v0.26.6

remoulade/middleware/max_memory.py

@@ -14,12 +14,16 @@
 #
 # You should have received a copy of the GNU Lesser General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
+import os
 import resource
+from typing import Optional
 
 from ..logging import get_logger
 from .middleware import Middleware
 
+#: The default max_memory (in kilobytes)
+DEFAULT_MAX_MEMORY = os.getenv("remoulade_max_memory", None)
+
 
 class MaxMemory(Middleware):
     """Middleware that stop a worker if its amount of resident memory exceed max_memory (in kilobytes)
@@ -30,11 +34,16 @@ class MaxMemory(Middleware):
       max_memory(int): The maximum amount of resident memory (in kilobytes)
     """
 
-    def __init__(self, *, max_memory: int):
+    def __init__(self, *, max_memory: Optional[int] = DEFAULT_MAX_MEMORY):
         self.logger = get_logger(__name__, type(self))
-        self.max_memory = max_memory
+        self.max_memory: Optional[int] = None
+        if max_memory is not None:
+            self.max_memory = int(max_memory)
 
     def after_worker_thread_process_message(self, broker, thread):
+        if self.max_memory is None:
+            return
+
         used_memory = resource.getrusage(resource.RUSAGE_SELF).ru_maxrss
         if used_memory <= 0:
             self.logger.error("Worker unable to determine memory usage")