Adds support for plotjuggler & improves parsing logic.

[adityapande-1995]

Addresses first part of #333, by fixing the parsing logic for conditional tags. Also includes plotjuggler in ros2_examples.

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This change is 

[adityapande-1995]

Had to add an exception for plotjuggler due to this error :

--- captured stderr ---
CMake Error at CMakeLists.txt:19 (add_library):
  Target "empty_using_plotjuggler" links to target "Qt5::Widgets" but the
  target was not found.  Perhaps a find_package() call is missing for an
  IMPORTED target, or an ALIAS target is missing?


CMake Error at CMakeLists.txt:19 (add_library):
  Target "empty_using_plotjuggler" links to target "Qt5::Concurrent" but the
  target was not found.  Perhaps a find_package() call is missing for an
  IMPORTED target, or an ALIAS target is missing?


CMake Error at CMakeLists.txt:19 (add_library):
  Target "empty_using_plotjuggler" links to target "Qt5::Svg" but the target
  was not found.  Perhaps a find_package() call is missing for an IMPORTED
  target, or an ALIAS target is missing?

Otherwise I think this should be applicable to all packages. Also shows up in CI.

[adityapande-1995]

I did see libqt5concurrent5 libqt5svg5 libqt5svg5-dev libqt5widgets5 are already installed, and not able to find a target called empty_without_plotjuggler :/

[EricCousineau-TRI]

empty_using_{name} is generated by the following code:

drake-ros/bazel_ros2_rules/ros2/resources/ros2bzl/scraping/ament_cmake.py

Lines 133 to 139 in 4c17af0

	def collect_ament_cmake_package_properties(name, metadata):
	# NOTE(hidmic): each package properties are analyzed in isolation
	# to preclude potential interactions if multiple packages were
	# brought into the same CMake run. The latter could be done for
	# speed
	with TemporaryDirectory(dir=os.getcwd()) as project_path:
	project_name = 'empty_using_' + name

To see the target, you would need to change the TemporaryDirectory, or add an option for "sandbox debugging" mode for the generated files.

My guess is that it indeed is missing find_package()?

[EricCousineau-TRI]

Adds plotjuggler and fixes parsing for it. [...]

Is this PR just meant to address Q1 of #333? Could you mention as much in the overview (just to make sure I've set expectations well)

If you're adding plotjuggler here, could you also add a plotjugger binary, and see what is necessary to ensure that the plugins are loadable via Bazel (without a ROS 2 workspace sourced)?

[adityapande-1995]

Working on colcon based CI here, though I was able to run plotjuggler with its plugins using bazel run @ros2//plotjuggler_plotjuggler , without ros plugins that is. Adding an example for ros2.

[adityapande-1995]

The problem here is the extra plugin libs that are not a part of any target and are tricky to add:

"${workspace_prefix}/lib/plotjuggler_ros/lib*.so*"

which would have to live entrirely in bazel_ros2_rules.

[EricCousineau-TRI]

can we just generate a {package}_plugins target that will glob patterns like that?

[adityapande-1995]

Okay, after a bit of investigation : plotjuggler-ros uses a Qt based plugin system instead of pluginlib, which ROS uses. This is causing problems with the parsing of plugins, and hence we do not have the plugins bundled up into a package. We do have a mechanism for parsing plugins, but that assumes we're doing things the ROS way. (

drake-ros/bazel_ros2_rules/ros2/resources/ros2bzl/templates.py

Line 106 in e2b2ca4

if 'plugin_libraries' in metadata:

)

Nothing in the package metadata specifies that we have plugins in plotjuggler-ros.
Plotjuggler itself just hardcodes what the path for the plugins is : https://github.com/facontidavide/PlotJuggler/blob/15dce41f598daed841bf2093aa10ebdf2aa1052f/plotjuggler_app/mainwindow.cpp#L560-L566.

i.e. we need some special rule tweaking here just for plotjuggler_ros.

[adityapande-1995]

Alright, we have a rollup target now that can load the required plugins :

cd ros2_examples_bazel_installed
bazel run //ros2_example_apps:plotjuggler

[EricCousineau-TRI]

i.e. we need some special rule tweaking here just for plotjuggler_ros.

gotcha, special-case makes sense then, thanks!

Alright, we have a rollup target now that can load the required plugins

can you post a screenshot confirming that it has loaded the ROS 2 topic plugin?

Reviewed 2 of 3 files at r1, 1 of 1 files at r2, 2 of 3 files at r3, 1 of 3 files at r4, 1 of 2 files at r5, 1 of 1 files at r6, 1 of 1 files at r7, all commit messages.
Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @adityapande-1995 and @ahcorde)

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bazel_ros2_rules/ros2/resources/ros2bzl/templates.py line 111 at r7 (raw file):

            for library in metadata['plugin_libraries']
        )
    # Add an exception for plotjuggler-ros, as it does not

nit Per your investigation above, it would help future readers to include more detail.

Can you mention it is using Qt plugins, and perhaps provide a link to plotjuggler code that details on this?

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bazel_ros2_rules/ros2/resources/ros2bzl/templates.py line 116 at r7 (raw file):

        prefix = "_opt_ros_humble/lib/plotjuggler_ros/"
        data.extend([
            prefix + "libDataLoadROS2.so",

nit These values may change.

Is it possible to simply glob these files?

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ros2_example_bazel_installed/WORKSPACE line 84 at r7 (raw file):

    # "rmw_fastrtps_cpp",
] + [
    # Extra packages

The notion of "extra" may be unclear.

I recommend putting these in the first list starting on L67.

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ros2_example_bazel_installed/ros2_example_apps/plotjuggler.py line 1 at r6 (raw file):

Previously, ahcorde (Alejandro Hernández Cordero) wrote…

#!/usr/bin/env python3
"""

We actually do not use shebangs inside Python files that will be executed via Bazel, as these files are not intended to be independently executable.

Aditya, can you remove the shebang?

[adityapande-1995]

Reviewable status: 6 of 9 files reviewed, 3 unresolved discussions (waiting on @ahcorde and @EricCousineau-TRI)

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ros2_example_bazel_installed/WORKSPACE line 84 at r7 (raw file):

Previously, EricCousineau-TRI (Eric Cousineau) wrote…

The notion of "extra" may be unclear.

I recommend putting these in the first list starting on L67.

Done.

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ros2_example_bazel_installed/ros2_example_apps/plotjuggler.py line 1 at r6 (raw file):

Previously, EricCousineau-TRI (Eric Cousineau) wrote…

We actually do not use shebangs inside Python files that will be executed via Bazel, as these files are not intended to be independently executable.

Aditya, can you remove the shebang?

Done.

[adityapande-1995]

Reviewable status: 6 of 9 files reviewed, 3 unresolved discussions (waiting on @ahcorde and @EricCousineau-TRI)

[adityapande-1995]

Reviewable status: 6 of 9 files reviewed, 2 unresolved discussions (waiting on @ahcorde and @EricCousineau-TRI)

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bazel_ros2_rules/ros2/resources/ros2bzl/templates.py line 116 at r7 (raw file):

Previously, EricCousineau-TRI (Eric Cousineau) wrote…

nit These values may change.

Is it possible to simply glob these files?

Done

[jwnimmer-tri]

Dismissed @ahcorde from a discussion.
Reviewable status: 6 of 9 files reviewed, 1 unresolved discussion (waiting on @EricCousineau-TRI)

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ros2_example_bazel_installed/WORKSPACE line 84 at r7 (raw file):

Previously, adityapande-1995 (Aditya Pande) wrote…

Done.

Now the list isn't sorted anymore ("Please keep this list sorted")