[Garden] Download models in the background

[ahcorde]

🎉 New feature

• Closes Download Fuel models on the background #1260

Summary

it requires gazebosim/sdformat#1027

I was trying to add this functionality to Citadel, but we need to load a simple world when we are downloading the models, this simple world will add a name to the Scene which in most of the cases is not going to match with the desired world name.

This will generate that SceneBroadcaster will create some topics with undesired names. Using the reset API I can create the desired topics but, the old topics are still there.

Example:

/clock
/gazebo/resource_paths
/gui/camera/pose
/stats
/world/empty_world/clock
/world/empty_world/dynamic_pose/info
/world/empty_world/pose/info
/world/empty_world/scene/deletion
/world/empty_world/scene/info
/world/empty_world/state
/world/empty_world/stats
/world/shapes/dynamic_pose/info
/world/shapes/pose/info
/world/shapes/scene/deletion
/world/shapes/scene/info
/world/shapes/state

Another issue happens in the Physics thread, sometimes some links are not added. Myabe a race condition ?

It builds on top of #1327

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[mjcarroll]

I think that the merge is okay. It may be cleaner to rebase on main at this point, though?

[mjcarroll]

This seems odd, did it come in from the merge from main?

/github/workspace/src/Server.cc: In member function 'void gz::sim::v7::Server::Init()':
  /github/workspace/src/Server.cc:207:43: error: 'class sdf::v13::Root' has no member named 'WorldNameFromFile'
    207 |     auto errors2 = this->dataPtr->sdfRoot.WorldNameFromFile(

[ahcorde]

This seems odd, did it come in from the merge from main?

/github/workspace/src/Server.cc: In member function 'void gz::sim::v7::Server::Init()':
  /github/workspace/src/Server.cc:207:43: error: 'class sdf::v13::Root' has no member named 'WorldNameFromFile'
    207 |     auto errors2 = this->dataPtr->sdfRoot.WorldNameFromFile(

@mjcarroll This is not merged yet gazebosim/sdformat#1027

[mjcarroll]

@mjcarroll This is not merged yet gazebosim/sdformat#1027

Ah, sorry didn't catch that. Looks like it has an approval, do you want to merge/release or wait for @chapulina ?

[chapulina]

do you want to merge/release or wait for @chapulina ?

Don't wait for me on the SDF PR 🚢

[jennuine]

Just an initial pass

[jennuine]

Why not use this->dataPtr->sdfRoot directly?

Suggested change

	errors = root.LoadSdfString(
	this->dataPtr->config.SdfString());
	this->dataPtr->sdfRoot = root.Clone();
	errors = this->dataPtr->sdfRoot.LoadSdfString(
	this->dataPtr->config.SdfString());

Below as well

[jennuine]

When does DownloadInParallel get set to false?

[ahcorde]

in src/gz.cc

[jennuine]

I see it get set to true but I never see if it get set to false

[nkoenig]

@ahcorde see #1669 as an alternative that doesn't need the restart feature.

[azeey]

Closing in favor of #1669