Ros2cli diagnostics tool

[russkel]

Adds a ros2 CLI tool:

TODO

• rename to ros2diagnostics to follow convention
• as per your suggestion change verbs to list/echo.
• convert csv to an output format option on echo: ros2 diagnostics echo -f csv > my-csv.csv (unix philosophy)
  • add yaml/json output
• refactor DiagnosticsParser into a generator with a WaitSet and remove mode
• add self test verb
• add tests

Replaces #301

[nnarain]

Hey @russkel

This is something I'm interested in, any plans to complete the work here?

[russkel]

Hey @russkel

This is something I'm interested in, any plans to complete the work here?

Hello @nnarain, it absolutely is. Other priorities have prevented me from moving on this further. Hopefully some time will free up soonish. What particular part were you interested?

[nnarain]

At my company we are making the slow migration to ROS 2. Tools like this are a nice QoL during development and a lot of people are used to using rosdiagnostic command (we actually use the output for the ssh login text). Not something I can't do without for now, but definitively a nice to have. :)