Profile debug script which fetches a way from OSM

[systemed]

Issue

When debugging profile issues (e.g. #5892), it's useful to be able to see instantly what the profile is calculating for a given way, without having to reprocess a whole OSM extract.

This short script fetches a way from the OSM API and runs the requested Lua profile over it, then prints the result:

$ lua5.1 debug_way.lua car 14672606
{ 
  highway = 'residential',
  maxspeed = '45 mph',
  name = 'E0770 Road',
  ['source:maxspeed'] = '45 in Blaine County unless otherwise posted.',
  ['tiger:cfcc'] = 'A41',
  ['tiger:county'] = 'Blaine, OK',
  ['tiger:name_base'] = 'E0770',
  ['tiger:name_type'] = 'Rd',
  ['tiger:reviewed'] = 'no' 
}
=>
{ 
  backward_classes = {},
  backward_mode = 1,
  backward_rate = 16.09,
  backward_speed = 57.924,
  duration = 0,
  forward_classes = {},
  forward_mode = 1,
  forward_rate = 16.09,
  forward_speed = 57.924,
  is_left_hand_driving = false,
  is_startpoint = true,
  name = 'E0770 Road',
  road_classification = { 
    may_be_ignored = false,
    road_priority_class = 10 
  } 
}

It uses the existing debug handler (tweaked to not error on the missing get_location_tag C++ method) and builds upon the example profile_debugger.lua script.

I use a similar script to this for cycle.travel and have found it enormously helpful in debugging profile issues.

Tasklist

• CHANGELOG.md entry (How to write a changelog entry)
• update relevant Wiki pages
• add tests (see testing documentation
• review
• adjust for comments
• cherry pick to release branch

Requirements / Relations

Required Lua libraries are listed in the comments at the top of the script.

[jcoupey]

Handy script indeed, just tested it.

[jcoupey]

It looks like luasec isn't really required? I got an error all right prior to installing xml2lua but nothing related to not having run luarocks install luasec.

[systemed]

I've rephrased the comment to note that you may have this already (my Ubuntu box and Mac didn't).

[jcoupey]

My system (Ubuntu) currently does not have lua5.1 installed but lua5.2 which is also accessible via the lua generic command. If the same apply across other systems, pointing to simply lua would make it more generic.

[akashihi]

I guess it applies not only for ubuntu, so indeed, this needs to be just lua

[systemed]

No problem, changed (blame Homebrew for this one ;) ).

[akashihi]

Please replace docs references to 5.1 with more generic references to lua