Vmware /api/compute_resources/:id/available_storage_domains does not work if a deployment is in progress

Problem:

Making a GET to /api/compute_resources/:id/available_storage_domains does not work if a deployment is in progress (cloning a template for example)

Expected outcome:

I expecrt the API call to work just fine even if a deployment is running.

Foreman and Proxy versions:

Foreman: 1.21.3
Smart Proxy: 1.20.1

Foreman and Proxy plugin versions:

I dont know how to retrieve this information.

Other relevant data:
[e.g. logs from Foreman and/or the Proxy, modified templates, commands issued, etc]
(for logs, surround with three back-ticks to get proper formatting, e.g.)

2019-09-20T10:57:57 [I|app|5df7e4b7] Started GET "/api/compute_resources/2/available_storage_domains" for 10.66.2.59 at 2019-09-20 10:57:57 -0400
2019-09-20T10:57:57 [I|app|5df7e4b7] Processing by Api::V2::ComputeResourcesController#available_storage_domains as JSON
2019-09-20T10:57:57 [I|app|5df7e4b7]   Parameters: {"apiv"=>"v2", "id"=>"2", "compute_resource"=>{}}
2019-09-20T10:57:57 [I|app|5df7e4b7] Authorized user admin(Engineering Operations)
2019-09-20T10:57:57 [I|app|5df7e4b7] Current user set to admin (admin)
2019-09-20T10:57:57 [W|app|5df7e4b7] Action failed
NameError: uninitialized constant Fog::Compute::Vsphere::Datastore
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/core_ext/string/inflections.rb:68:in `constantize'
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:358:in `block in read'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:663:in `block in instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/notifications.rb:170:in `instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:663:in `instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache.rb:345:in `read'
/usr/share/foreman/app/services/compute_resource_cache.rb:34:in `read'
/usr/share/foreman/app/services/compute_resource_cache.rb:19:in `cache'
/usr/share/foreman/app/models/compute_resources/foreman/model/vmware.rb:108:in `datastores'
/usr/share/foreman/app/models/compute_resources/foreman/model/vmware.rb:172:in `available_storage_domains'
/usr/share/foreman/app/controllers/api/v2/compute_resources_controller.rb:139:in `available_storage_domains'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal/basic_implicit_render.rb:6:in `send_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/abstract_controller/base.rb:194:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal/rendering.rb:30:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/abstract_controller/callbacks.rb:42:in `block in process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:109:in `block in run_callbacks'
/usr/share/foreman/app/controllers/api/v2/base_controller.rb:163:in `disable_json_root'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:118:in `block in run_callbacks'
/usr/share/foreman/app/controllers/concerns/application_shared.rb:15:in `set_timezone'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:118:in `block in run_callbacks'
/usr/share/foreman/app/models/concerns/foreman/thread_session.rb:32:in `clear_thread'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:118:in `block in run_callbacks'
/usr/share/foreman/app/controllers/concerns/foreman/controller/topbar_sweeper.rb:12:in `set_topbar_sweeper_controller'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:118:in `block in run_callbacks'
/opt/theforeman/tfm/root/usr/share/gems/gems/audited-4.7.1/lib/audited/sweeper.rb:14:in `around'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:118:in `block in run_callbacks'
/opt/theforeman/tfm/root/usr/share/gems/gems/audited-4.7.1/lib/audited/sweeper.rb:14:in `around'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:118:in `block in run_callbacks'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/callbacks.rb:136:in `run_callbacks'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/abstract_controller/callbacks.rb:41:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal/rescue.rb:22:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal/instrumentation.rb:34:in `block in process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/notifications.rb:168:in `block in instrument'
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/notifications.rb:168:in `instrument'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal/instrumentation.rb:32:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal/params_wrapper.rb:256:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activerecord-5.2.1/lib/active_record/railties/controller_runtime.rb:24:in `process_action'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/abstract_controller/base.rb:134:in `process'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionview-5.2.1/lib/action_view/rendering.rb:32:in `process'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal.rb:191:in `dispatch'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_controller/metal.rb:252:in `dispatch'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/routing/route_set.rb:52:in `dispatch'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/routing/route_set.rb:34:in `serve'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/routing/mapper.rb:18:in `block in <class:Constraints>'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/routing/mapper.rb:48:in `serve'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/journey/router.rb:52:in `block in serve'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/journey/router.rb:35:in `each'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/journey/router.rb:35:in `serve'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/routing/route_set.rb:840:in `call'
/opt/theforeman/tfm/root/usr/share/gems/gems/apipie-rails-0.5.14/lib/apipie/static_dispatcher.rb:65:in `call'
/opt/theforeman/tfm/root/usr/share/gems/gems/apipie-rails-0.5.14/lib/apipie/extractor/recorder.rb:137:in `call'
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/static.rb:127:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/static.rb:127:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/static.rb:127:in `call'
/usr/share/foreman/lib/foreman/middleware/telemetry.rb:10:in `call'
/opt/theforeman/tfm/root/usr/share/gems/gems/apipie-rails-0.5.14/lib/apipie/middleware/checksum_in_headers.rb:27:in `call'
/usr/share/foreman/lib/foreman/middleware/catch_json_parse_errors.rb:9:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/tempfile_reaper.rb:15:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/etag.rb:25:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/conditional_get.rb:25:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/head.rb:12:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/http/content_security_policy.rb:18:in `call'
/usr/share/foreman/lib/foreman/middleware/logging_context_session.rb:22:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/session/abstract/id.rb:232:in `context'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/session/abstract/id.rb:226:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/cookies.rb:670:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/callbacks.rb:26:in `call'
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/request_id.rb:27:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/method_override.rb:22:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/runtime.rb:22:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/activesupport-5.2.1/lib/active_support/cache/strategy/local_cache_middleware.rb:29:in `call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/actionpack-5.2.1/lib/action_dispatch/middleware/executor.rb:14:in `call'
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/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/railties-5.2.1/lib/rails/railtie.rb:190:in `public_send'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/railties-5.2.1/lib/rails/railtie.rb:190:in `method_missing'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/urlmap.rb:68:in `block in call'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/urlmap.rb:53:in `each'
/opt/theforeman/tfm-ror52/root/usr/share/gems/gems/rack-2.0.5/lib/rack/urlmap.rb:53:in `call'
/usr/share/passenger/phusion_passenger/rack/thread_handler_extension.rb:74:in `process_request'
/usr/share/passenger/phusion_passenger/request_handler/thread_handler.rb:141:in `accept_and_process_next_request'
/usr/share/passenger/phusion_passenger/request_handler/thread_handler.rb:109:in `main_loop'
/usr/share/passenger/phusion_passenger/request_handler.rb:455:in `block (3 levels) in start_threads'
/opt/theforeman/tfm/root/usr/share/gems/gems/logging-2.2.2/lib/logging/diagnostic_context.rb:474:in `block in create_with_logging_context'
2019-09-20T10:57:57 [I|app|5df7e4b7]   Rendering api/v2/errors/standard_error.json.rabl within api/v2/layouts/error_layout
2019-09-20T10:57:57 [I|app|5df7e4b7]   Rendered api/v2/errors/standard_error.json.rabl within api/v2/layouts/error_layout (1.1ms)
2019-09-20T10:57:57 [I|app|5df7e4b7] Completed 500 Internal Server Error in 90ms (Views: 3.1ms | ActiveRecord: 15.5ms)