[BtActionServer] default enable_groot_monitoring_ to false to solve Original error: Address already in use migration error

[doisyg]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses	(add tickets here #1)
Primary OS tested on	Ubuntu
Robotic platform tested on	Dexory simulation
Does this PR contain AI generated software?	No

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Description of contribution in a few bullet points

Since #5065, groot monitoring is enabled by default for all BtActionServers :

navigation2/nav2_behavior_tree/include/nav2_behavior_tree/bt_action_server.hpp

Line 288 in 7f561b0

bool enable_groot_monitoring_ = true;

This causes issue for users of simple BtActionServers that by default are not calling setGrootMonitoring:

navigation2/nav2_behavior_tree/include/nav2_behavior_tree/bt_action_server_impl.hpp

Line 239 in 7f561b0

void BtActionServer<ActionT>::setGrootMonitoring(const bool enable, const unsigned server_port)

.
And hence, if they have more than one such action, they are faced with a Original error: Address already in use error.

Description of documentation updates required from your changes

Description of how this change was tested

Full launch of Dexory stack

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Future work that may be required in bullet points

For non BehaviorTreeNavigator actions, it would have been simpler to have enable_groot_monitoring and groot_server_port as parameters of BtActionServer (like for instance bt_loop_duration, default_server_timeout, wait_for_service_timeout and always_reload_bt_xml) but I understand the need for being able to set different values for 2 different pluggins of 1 bt_navigator.
Or maybe a future work could combine both ?

For Maintainers:

• Check that any new parameters added are updated in docs.nav2.org
• Check that any significant change is added to the migration guide
• Check that any new features OR changes to existing behaviors are reflected in the tuning guide
• Check that any new functions have Doxygen added
• Check that any new features have test coverage
• Check that any new plugins is added to the plugins page
• If BT Node, Additionally: add to BT's XML index of nodes for groot, BT package's readme table, and BT library lists

[ajtudela]

Hi @doisyg, I implemented the feature. Could you provide more details about your implementation so I can troubleshoot the error?

If I understand correctly, you have two BtActionServer running at the same time and, because enable_groot_monitoring_ is set in the class, the ports collide and throw an error.

I apologize for that; I didn't consider a use case for BtActionServer outside of Navigators.

I'll look into combining the parameters of the BtActionServer with the navigator plugins.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Files with missing lines	Coverage Δ
...ee/include/nav2_behavior_tree/bt_action_server.hpp	83.33% <ø> (ø)

... and 7 files with indirect coverage changes

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[doisyg]

If I understand correctly, you have two BtActionServer running at the same time and, because enable_groot_monitoring_ is set in the class, the ports collide and throw an error.

Exactly, and more than 2!

I apologize for that; I didn't consider a use case for BtActionServer outside of Navigators.

No worries, as there are no such use cases in nav2, it was not necessarily straightforward to foresee.

I'll look into combining the parameters of the BtActionServer with the navigator plugins.

I am not even 100% sure it is worth the trouble. If a non Navigators user of a BtActionServer needs Groot monitoring, he could for now call setGrootMonitoring in its code. I will let @SteveMacenski recommend the best solution.

[SteveMacenski]

This is very reasonable, we disable it anyway in the nav2 params defaults

navigation2/nav2_bringup/params/nav2_params.yaml

Line 55 in 7f561b0

enable_groot_monitoring: false

I think this is the right answer