RailwayJp

Japanese railway lines and stations as Ruby objects. The data ships inside the gem, so lookups need no database and no network.

Ruby 3.4 or newer.

$ bundle add railway_jp

Or add it to your Gemfile by hand:

gem 'railway_jp'

find takes an id as either an Integer or a String, and returns nil when nothing matches.

station = RailwayJp::Station.find(2800209)

station.id             # => "2800209"
station.name           # => "東京"
station.line_id        # => "28002"
station.prefecture_id  # => "13"
station.postcode       # => "100-0005"
station.address        # => "東京都千代田区丸の内一丁目"
station.longitude      # => "139.764708"
station.latitude       # => "35.681753"

Every attribute is a String, coordinates included, so convert them yourself if you need numbers.

RailwayJp::Station.all returns every station. The data also covers stations that are no longer in service, and all does not filter those out.

A station carries its line:

station.line_name  # => "東京メトロ丸ノ内線"

line = station.line
line.id     # => "28002"
line.name   # => "東京メトロ丸ノ内線"
line.color  # => "E60012"

color is a six digit RGB hex string with no leading #. It is nil for most lines, since only a small part of the data carries one.

RailwayJp::Line.find and RailwayJp::Line.all behave like their Station counterparts.

Records compare by class and id, so the same station loaded twice is equal and deduplicates:

a = RailwayJp::Station.find(2800209)
b = RailwayJp::Station.find(2800209)

a == b          # => true
[a, b].uniq     # => [a]

Run bin/setup to install dependencies, bundle exec rake to run the specs and RuboCop, and bin/console for a session with the gem loaded.

Run the Release workflow from the Actions tab and choose patch, minor or major. It bumps the version, tags it, creates the GitHub release and publishes to RubyGems through trusted publishing.

Bug reports and pull requests are welcome at https://github.com/d-mato/railway_jp.

Available as open source under the terms of the MIT License.