[IMP] queue_job: Configure default subchannel capacity.

This adds a new `subcapacity` option to channels that allows the
configuration of the default capacity for autocreated child channels.

For example, environment `ODOO_QUEUE_JOB_CHANNELS=root:8:subcapacity=1`
would set the capacity of an autocreated `root.sub` channel to 1.

Author: amh-mw

queue_job/jobrunner/channels.py

@@ -381,7 +381,9 @@ class Channel:
     without risking to overflow the system.
     """
 
-    def __init__(self, name, parent, capacity=None, sequential=False, throttle=0):
+    def __init__(
+        self, name, parent, capacity=None, sequential=False, throttle=0, subcapacity=0
+    ):
         self.name = name
         self.parent = parent
         if self.parent:
@@ -391,9 +393,10 @@ def __init__(self, name, parent, capacity=None, sequential=False, throttle=0):
         self._running = set()
         self._failed = set()
         self._pause_until = 0  # utc seconds since the epoch
-        self.capacity = capacity
+        self.capacity = capacity or (parent and parent.subcapacity) or None
         self.throttle = throttle  # seconds
         self.sequential = sequential
+        self.subcapacity = subcapacity
 
     @property
     def sequential(self):
@@ -410,11 +413,13 @@ def configure(self, config):
 
         * capacity
         * sequential
+        * subcapacity
         * throttle
         """
         assert self.fullname.endswith(config["name"])
         self.capacity = config.get("capacity", None)
         self.sequential = bool(config.get("sequential", False))
+        self.subcapacity = int(config.get("subcapacity", 0))
         self.throttle = int(config.get("throttle", 0))
         if self.sequential and self.capacity != 1:
             raise ValueError("A sequential channel must have a capacity of 1")

queue_job/tests/test_runner_channels.py

@@ -1,10 +1,43 @@
 # Copyright 2015-2016 Camptocamp SA
 # License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl.html)
 
+from odoo.tests import BaseCase
+
 # pylint: disable=odoo-addons-relative-import
 # we are testing, we want to test as we were an external consumer of the API
 from odoo.addons.queue_job.jobrunner import channels
 
 from .common import load_doctests
 
 load_tests = load_doctests(channels)
+
+
+class TestChannelManager(BaseCase):
+    def test_subcapacity_default(self):
+        cm = channels.ChannelManager()
+        cm.simple_configure("root:4")
+        root = cm.get_channel_by_name("root")
+        self.assertEqual(root.capacity, 4)
+        self.assertEqual(root.subcapacity, 0)
+        child = cm.get_channel_by_name("child", autocreate=True)
+        self.assertIs(child.capacity, None)
+        self.assertEqual(child.subcapacity, 0)
+
+    def test_subcapacity(self):
+        cm = channels.ChannelManager()
+        cm.simple_configure("root:4:subcapacity=1,override:2")
+        root = cm.get_channel_by_name("root")
+        self.assertEqual(root.subcapacity, 1)
+        child = cm.get_channel_by_name("override")
+        self.assertEqual(child.capacity, 2)
+        self.assertEqual(child.subcapacity, 0)
+        child = cm.get_channel_by_name("child", autocreate=True)
+        self.assertEqual(child.capacity, 1)
+        self.assertEqual(child.subcapacity, 0)
+
+    def test_subcapacity_subchannel(self):
+        cm = channels.ChannelManager()
+        cm.simple_configure("root:4,sub:2:subcapacity=1")
+        child = cm.get_channel_by_name("sub.child", autocreate=True)
+        self.assertEqual(child.capacity, 1)
+        self.assertEqual(child.subcapacity, 0)