[18.0][IMP] queue_job: Configure default subchannel capacity.

[amh-mw]

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.

[OCA-git-bot]

Hi @guewen,
some modules you are maintaining are being modified, check this out!

[sbidoul]

This looks good, thanks!

Could expand the docstring of parse_simple_config a bit (around line 823).

The only question I'd have is if we can come up for a better name to convey "default subchannel capacity". I don't have any better idea for now.

[amh-mw]

The only question I'd have is if we can come up for a better name to convey "default subchannel capacity". I don't have any better idea for now.

Given existing documentation:

Channels: give a capacity for the root channel and its sub-channels and segregate jobs in them. Allow for instance to restrict heavy jobs to be executed one at a time while little ones are executed 4 at a times.

Noodling around in tests:

cm = channels.ChannelManager()
cm.simple_configure("root:2,child")
root = cm.get_channel_by_name("root")
self.assertEqual(root.capacity, 2)
child = cm.get_channel_by_name("child")
self.assertEqual(child.capacity, 1)
auto = cm.get_channel_by_name("auto", autocreate=True)
self.assertEqual(auto.capacity, None)

The difference in capacity between an autocreated subchannel and a configured subchannel was the impetus for the creation of this pull request. Maybe rename subcapacity to autocapacity? Testing shows that the new setting does not change the capacity for configured subchannels.

cm = channels.ChannelManager()
cm.simple_configure("root:4:subcapacity=2,child")
root = cm.get_channel_by_name("root")
self.assertEqual(root.capacity, 4)
child = cm.get_channel_by_name("child")
self.assertEqual(child.capacity, 1)