Generating code for ros action files

[exo-core]

with this changes the message generation also creates files for ROS action files.
This should also resolve this issue.

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[exo-core]

I sold my sou... eh, signed it.

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CLAs look good, thanks!

[jubeira]

Thanks for this wonderful contribution @exo-core!

I took a quick look and codewise it looks good. I'll give it a shot when I have some time and I will approve it if everything goes well.

[jubeira]

@exo-core I tried the changes and they seem to work well.

I only have one observation: this will generate the action message artifacts when add_message_files + generate_messages macros are present in CMakeLists; is that right or am I missing something? In other words, you wouldn't need to add add_action_files macro to CMakeLists.

While I think that it's better to have this than not to have it, this is a small difference wrt. the regular action message generation in roscpp and rospy that is worth pointing out.

[exo-core]

@jubeira you're completely right with your oberservation.

There is a comment in enjava/src/genjava/templates/genjava_project/build.gradle.in about the message generator:

/* Damon's message generator doesn't catch every message. It expects everything to be nicely under 'msg'
 * and that directory to be under the package root. It also expects every msg it finds should be buildable.
 * It kinda works until now because it ignores any package which doesn't conform to this and those are just
 * test packages (we hope).

from what I saw in the code rosjava bootstrap simply crawls the msg directory and compiles everything that hast a *.msg file type. They same happens for services. Basically all I did was copying the ServiceFileProvider and refactor it to do the same for the action directory.

So, yes, the current generator ignores all the add_message_files, add_service_files and add_action_files macros in CMakeLists.txt and just builds everything it finds in the according folders.

Changing the behaviour to be the same as for C++ or Python would probably require to rewrite the whole message discovery procedure.

[jubeira]

Thanks for the changes and the observations @exo-core! PR merged :)