Fit4Ruby

Fit4Ruby is a http://www.ruby-lang.org libary to read and write FIT files.

This libary is still work in progress and probably not yet ready to be used in your application. However, you are welcome to try it and send me comments and patches. It was developed to form the back-end of https://github.com/scrapper/postrunner.

Supported Devices

Tested devices: Garmin FR620, Fenix 3, Fenix 5, Fenix 5X, Fenix 6X

Other Garmin devices that generate FIT files may work as well. Since I don't have any other devices, I can't add support for them.

Supported Operating Systems

This library was developed and tested on Linux using Ruby 2.0 (MRI). Other operating systems that are Supported by Ruby 2.0 may probably work as well.

Usage

You can create an Activity.

require 'fit4ruby'

a = Fit4Ruby::Activity.new
a.total_timer_time = 30 * 60
a.new_user_profile({ :age => 33, :height => 1.78, :weight => 73.0,
                     :gender => 'male', :activity_class => 4.0,
                     :max_hr => 178 })

a.new_event({ :event => 'timer', :event_type => 'start_time' })
a.new_device_info({ :device_index => 0 })
a.new_device_info({ :device_index => 1, :battery_status => 'ok' })
ts = Time.now
0.upto(a.total_timer_time / 60) do |mins|
  ts += 60
  a.new_record({
    :timestamp => ts,
    :position_lat => 51.5512 - mins * 0.0008,
    :position_long => 11.647 + mins * 0.002,
    :distance => 200.0 * mins,
    :altitude => 100 + mins * 2,
    :speed => 3.1,
    :vertical_oscillation => 9 + mins * 0.02,
    :stance_time => 235.0 * mins * 0.01,
    :stance_time_percent => 32.0,
    :heart_rate => 140 + mins,
    :cadence => 75,
    :activity_type => 'running',
    :fractional_cadence => (mins % 2) / 2.0
  })

  if mins > 0 && mins % 5 == 0
    a.new_lap({ :timestamp => ts })
  end
end
a.new_session({ :timestamp => ts })
a.new_event({ :timestamp => ts, :event => 'recovery_time',
              :event_type => 'marker',
              :data => 2160 })
a.new_event({ :timestamp => ts, :event => 'vo2max',
              :event_type => 'marker', :data => 52 })
a.new_event({ :timestamp => ts, :event => 'timer',
              :event_type => 'stop_all' })
a.new_device_info({ :timestamp => ts, :device_index => 0 })
ts += 1
a.new_device_info({ :timestamp => ts, :device_index => 1,
                    :battery_status => 'low' })
ts += 120
a.new_event({ :timestamp => ts, :event => 'recovery_hr',
              :event_type => 'marker', :data => 132 })

Now you can have the accumulated data for laps and sessions computed.

a.aggregate

Save it to a file.

Fit4Ruby.write('TEST.FIT', a)

Or read an Activity from a file.

a = Fit4Ruby.read('TEST.FIT')

Then you can access the data in the file.

a.records.each do |r|
  puts "Latitude: #{r.get 'position_lat'}"
  puts "Longitude: #{r.get 'position_long'}"
end

Please see GlobalFitMessages.rb for the data fields that are supported for the various FIT record types.

License

See COPYING file.