Quick wrapper around the Purple WiFI API

purple_api_connection.rb

require "time"
require "uri"
require "net/http"
require "json"

class PurpleAPIConnection
  HOST = "purpleportal.net"
  API_PATH = "/api/company/v1"
  CONTENT_TYPE = "application/json"

  attr_reader :uri, :response

  def initialize(public_key, private_key)
    @public_key = public_key
    @private_key = private_key
  end

  def get_venues
    get("venues")
    parsed_response.dig("data", "venues")
  end

  def get_venue(venue_id)
    get("venue/#{venue_id}")
    parsed_response.dig("data", "venues")&.first
  end

  def get_venue_occupancy(venue_id)
    get("venue/#{venue_id}/occupancy/sensors")
    parsed_response.dig("data")
  end

  def get(endpoint, params = {})
    @uri = URI("https://#{host}#{api_path}/#{endpoint}")
    @uri.query = URI.encode_www_form(params)
    @response =
      Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |http| http.request(request) }
  end

  private

  def host
    HOST
  end

  def api_path
    API_PATH
  end

  def content_type
    CONTENT_TYPE
  end

  def parsed_response
    @response.is_a?(Net::HTTPSuccess) ? JSON.parse(@response.body) || {} : {}
  end

  def request
    req = Net::HTTP::Get.new(uri)
    req["Content-Type"] = content_type
    req["Date"] = Time.now.httpdate
    req["X-API-Authorization"] = "#{@public_key}:#{token}"
    req
  end

  def path_and_query
    [uri.path, uri.query].compact.join("?")
  end

  def token
    token_data = [content_type, host, path_and_query, Time.now.httpdate, nil, nil].join("\n")
    hash_for_token(token_data)
  end

  def hash_for_token(data)
    OpenSSL::HMAC.hexdigest("SHA256", @private_key, data)
  end
end

Usage:

require "purple_api_connection.rb"

connection = PurpleAPIConnection.new("PUBLIC_KEY", "PRIVATE_KEY")
connection.get_venues