Simple Ruby CSV-to-GeoJSON command line utility

csv2geojson.rb

#!/bin/ruby

require 'smarter_csv'
require 'json'
require 'optparse'

class Csv2GeoJson

  attr_reader :csv_source
  attr_reader :lat_header
  attr_reader :lon_header
  attr_reader :geojson

  def initialize(source)
    @csv_source = source
    @lat_header = nil
    @lon_header = nil
    @has_headers = true
    @features = []
  end

  def map_lat_from(field_name)
    @lat_header = field_name
    self
  end

  def map_lon_from(field_name)
    @lon_header = field_name
    self
  end

  def has_headers(has_headers)
    @has_headers = has_headers
    self
  end

  def run
    SmarterCSV.process(@csv_source, :headers_in_file => @has_headers).each do |row|
      lat = row[@lat_header]
      lon = row[@lon_header]
      properties = {}
      row.each do |header, field|
        properties[header] = field unless header == @lat_header || header == @lon_header
      end
      @features.push({
        type: 'Feature',
        geometry: {
          type: 'Point',
          coordinates: [lon.to_f, lat.to_f]
        },
        properties: properties
      })
    end

    @geojson = {
      type: 'FeatureCollection',
      crs: {
        type: 'name',
        properties: {
          name: 'urn:ogc:def:crs:OGC:1.3:CRS84'
        }
      },
      features: @features
    }
  end

end


options = {
  lat: nil,
  lon: nil,
  no_headers: false
}

OptionParser.new do |opts|
  opts.banner = 'csv2geojson usage:'

  opts.on('--lat FIELD', 'the name of the header or column index containing the latitude values') \
    do |field|
    options[:lat] = field
  end

  opts.on('--lon FIELD', 'the name of the header or column index containing the longitude values') \
    do |field|
    options[:lon] = field
  end

  opts.on('--no-headers', 'indicate there is no header row') \
    do
    options[:no_headers] = true
  end
end.parse!(ARGV)


geojson_hash = Csv2GeoJson.new(ARGF)
  .map_lat_from(options[:lat])
  .map_lon_from(options[:lon])
  .has_headers(!options[:no_headers])
  .run

puts JSON.pretty_generate(geojson_hash)