Feature/planner visualizer

[aaronchongth]

Starting this PR to get feedback as the frontend gets developed. The current idea is the backend/server will receive all the necessary information from the UI to create a planner and its corresponding debugger. The Graph for the planner is more tricky, and I plan to have the UI select a file location from the browser, which the server expects to be an absolute path, to create GraphInfo instance using ParseGraph (a modified version from rmf_fleet_adapters.

• used the debugger API to create planning visualization backend, modelled after the schedule visualizer
• ParseGraph was taken from rmf_core, https://github.com/osrf/rmf_core/blob/master/rmf_fleet_adapter/src/rmf_fleet_adapter/ParseGraph.hpp, with some modifications
• moved the json header to a common interface library visualizer_utils
• currently a planning state json response has been committed to romi-dashboard for frontend development and testing, https://github.com/osrf/romi-dashboard/blob/master/src/mock/data/planning_state.json

Branched off develop, currently building with rmf_core commit 69f496b

TODO:

• schedule visualizer to use json from interface library as well
• test response from UI

[koonpeng]

The Graph for the planner is more tricky, and I plan to have the UI select a file location from the browser, which the server expects to be an absolute path, to create GraphInfo instance using ParseGraph (a modified version from rmf_fleet_adapters.

I haven't look at the code but this screams a lot of problems with access control. I'm assuming the plan is to visualize a previously created graph, you could use the File API to open a file on the client side or have the server present a list of handles that the client can select.

[aaronchongth]

I like the idea of server presenting list of handles for the client, thanks for the input! I will make the changes accordingly