Add Batch environment variables to pool start task

[jackpimbert]

Feature Request Description

I would like to use the Azure batch insights to get some simple monitoring information via the Batch Explorer. To do so looks fairly straight forward, however I need to add some Batch environment variables that can be seen on start of a vm in a pool, and also from Batch Explorer. Therefore, using export isn't enough and instead the environment variables need to be added within the start task, e.g.

batch-shipyard/convoy/fleet.py

Lines 1520 to 1523 in 296c39b

	environment_settings=[
	batchmodels.EnvironmentSetting(
	name='LC_ALL', value='en_US.UTF-8'),
	],

Describe Preferred Solution

An option in the pool configuration to add custom environment variables, as is possible within the jobs configuration.

Please let me know if there's another way of adding environment variables to the start task, such that they will be included as Batch environment variables and seen within the Batch Explorer, thanks!

[alfpark]

Would it be helpful to provide direct Batch App Insights integration? This was on my backlog but instead opted for a full Prometheus/Grafana monitoring solution that aligns with an open source solution providing container-level metrics.

[jackpimbert]

I would find it useful as a lighter weight monitoring solution in comparison to using Prometheus/Grafana. In our current use case it works better, although we may end up going for the full solution in the future.

[jackpimbert]

Should I close this issue now that #253 has been merged in?

[alfpark]

The issue will auto-close when the commit is merged to master.

The Batch Insights integration has been merged to develop in #259.