Convert model:// to Fuel URLs instead of absolute paths

[chapulina]

Builds on top of #84 .

Resolves #77.

Summary

Without this PR, model:// URIs like this:

<uri>model://Radio/meshes/Radio.dae</uri>

Would become absolute paths like this:

<uri>/home/chapulina/.ignition/fuel/fuel.ignitionrobotics.org/OpenRobotics/models/Radio/4/meshes/Radio.dae</uri>

With this PR, it becomes a Fuel URL like this:

<uri>https://fuel.ignitionrobotics.org/1.0/OpenRobotics/models/Radio/4/files/meshes/Radio.dae</uri>

Resources across models

It's common for one model to use resources from other models to avoid duplication of resources. For example, the Radio model could use model://Phone/meshes/antenna,dae from the Phone model (assuming both.

For this to work on Blueprint and Citadel, Radio will need to use the full URL of the phone's antenna, i.e.

https://fuel.ignitionrobotics.org/1.0/OpenRobotics/models/Phone/4/files/meshes/antenna.dae.

From Dome onwards, the same owner will be assumed for both models, and

model://Phone/meshes/antenna,dae

will be converted to the URL above automatically.

The reason not to do this for Blueprint is that there's a non-trivial number of models on Fuel right now whose Fuel name doesn't match the model:// URI. These would look like different models which don't exist. For example, the Construction Cone uses model://construction_cone.

Right now, these models load fine, but a debug message is written:

[Dbg] [LocalCache.cc:583] Model [Construction Cone] loading resource from another model, named [construction_cone]. On Blueprint and Citadel, [construction_cone] is ignored. From Dome, [Construction Cone] will be used. If [construction_cone] is not a model belonging to owner [OpenRobotics], fix your SDF file!

[codecov]

Codecov Report

Merging #85 into ign-fuel-tools3 will increase coverage by 0.04%.
The diff coverage is 78.78%.

@@                 Coverage Diff                 @@
##           ign-fuel-tools3      #85      +/-   ##
===================================================
+ Coverage            85.70%   85.74%   +0.04%     
===================================================
  Files                   16       16              
  Lines                 2028     2041      +13     
===================================================
+ Hits                  1738     1750      +12     
- Misses                 290      291       +1     

Impacted Files	Coverage Δ
src/LocalCache.cc	79.51% <78.78%> (+0.52%)	⬆️

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[nkoenig]

Do you want to add a test, or save that for later?

[chapulina]

Do you want to add a test, or save that for later?

The tests in src/FuelClient_TEST.cc were updated to reflect the changes in this PR. They check that resource tags now start with https://. I didn't want to check the entire URL in case the model changes.

[nkoenig]

I'm seeing a lot of errors with models in Subt. For example:

[Err] [Ogre2MeshFactory.cc:430] Cannot load null mesh [https://fuel.ignitionrobotics.org/1.0/OpenRobotics/models/X1 Config 1/15/files/meshes/wheel.dae]

[chapulina]

I'm seeing a lot of errors with models in Subt. For example:

Those work for me. Are you running the latest commit of ign-gazebo2?

[nkoenig]

I'm seeing a lot of errors with models in Subt. For example:

Those work for me. Are you running the latest commit of ign-gazebo2?

That fixed the problem, however this change breaks gz3d. I'll have to fixed that library first.

[chapulina]

this change breaks gz3d. I'll have to fixed that library first.

Oh I hadn't thought of that. Maybe it's safer to target this at Dome to preserve backwards compatibility. Let me know how gz3d goes.

[nkoenig]

this change breaks gz3d. I'll have to fixed that library first.

Oh I hadn't thought of that. Maybe it's safer to target this at Dome to preserve backwards compatibility. Let me know how gz3d goes.

Here is the patch. I'll approve this PR so that we can eventually make new docker images for SubT.

https://gitlab.com/ignitionrobotics/web/gz3d/-/merge_requests/26