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Commit bacb490aa805c31365275b2390fa3fae238ddc15

Authored by Aurélio A. Heckert
1 parent 6b9d32eb
Exists in api_tasks and in 1 other branch api_fixies

Ads GeoRef lib

Showing 2 changed files with 142 additions and 2 deletions   Show diff stats
lib/noosfero/geo_ref.rb
  Diff comments   View file @bacb490
1 module Noosfero::GeoRef 1 module Noosfero::GeoRef
2 2
3 - KM_LAT = 111.2 # aproximate distance in km for 1 degree latitude  
4 - KM_LNG = 85.3 # aproximate distance in km for 1 degree longitude 3 + # May replace this module by http://www.postgresql.org/docs/9.3/static/earthdistance.html
  4 +
  5 + EARTH_RADIUS = 6378 # aproximate in km
  6 +
  7 + class << self
  8 +
  9 + def dist(lat1, lng1, lat2, lng2)
  10 + def deg2rad(d); (d*Math::PI)/180; end
  11 + def c(n); Math.cos(n); end
  12 + def s(n); Math.sin(n); end
  13 + lat1 = deg2rad lat1
  14 + lat2 = deg2rad lat2
  15 + dlng = deg2rad(lng2) - deg2rad(lng1)
  16 + EARTH_RADIUS * Math.atan2(
  17 + Math.sqrt(
  18 + ( c(lat2) * s(dlng) )**2 +
  19 + ( c(lat1) * s(lat2) - s(lat1) * c(lat2) * c(dlng) )**2
  20 + ),
  21 + s(lat1) * s(lat2) + c(lat1) * c(lat2) * c(dlng)
  22 + )
  23 + end
  24 +
  25 + # Write a SQL expression to return the distance from a profile to a
  26 + # reference point, in kilometers.
  27 + # http://www.plumislandmedia.net/mysql/vicenty-great-circle-distance-formula
  28 + def sql_dist(ref_lat, ref_lng)
  29 + "2*PI()*#{EARTH_RADIUS}*(
  30 + DEGREES(
  31 + ATAN2(
  32 + SQRT(
  33 + POW(COS(RADIANS(#{ref_lat}))*SIN(RADIANS(#{ref_lng}-lng)),2) +
  34 + POW(
  35 + COS(RADIANS(lat)) * SIN(RADIANS(#{ref_lat})) - (
  36 + SIN(RADIANS(lat)) * COS(RADIANS(#{ref_lat})) * COS(RADIANS(#{ref_lng}-lng))
  37 + ), 2
  38 + )
  39 + ),
  40 + SIN(RADIANS(lat)) * SIN(RADIANS(#{ref_lat})) +
  41 + COS(RADIANS(lat)) * COS(RADIANS(#{ref_lat})) * COS(RADIANS(#{ref_lng}-lng))
  42 + )
  43 + )/360
  44 + )"
  45 + end
  46 +
  47 + # Asks Google for the georef of a location.
  48 + def location_to_georef(location)
  49 + key = location.downcase
  50 + ll = Rails.cache.read key
  51 + return ll + [:CACHE] if ll.kind_of? Array
  52 + resp = RestClient.get 'https://maps.googleapis.com/maps/api/geocode/json?' +
  53 + 'sensor=false&address=' + url_encode(location)
  54 + if resp.nil? || resp.code.to_i != 200
  55 + if ENV['RAILS_ENV'] == 'test'
  56 + print " Google Maps API fail (code #{resp ? resp.code : :nil}) "
  57 + else
  58 + Rails.logger.warn "Google Maps API request information for " +
  59 + "\"#{location}\" fail. (code #{resp ? resp.code : :nil})"
  60 + end
  61 + return [ 0, 0, "HTTP_FAIL_#{resp.code}".to_sym ] # do not cache failed response
  62 + else
  63 + json = JSON.parse resp.body
  64 + if json && (r=json['results']) && (r=r[0]) && (r=r['geometry']) &&
  65 + (r=r['location']) && r['lat']
  66 + ll = [ r['lat'], r['lng'], :SUCCESS ]
  67 + else
  68 + status = json['status'] || 'Undefined Error'
  69 + message = "Google Maps API cant find \"#{location}\" (#{status})"
  70 + if ENV['RAILS_ENV'] == 'test'
  71 + print " #{message} "
  72 + else
  73 + Rails.logger.warn message
  74 + end
  75 + ll = [ 0, 0, status.to_sym ]
  76 + end
  77 + Rails.cache.write key, ll
  78 + end
  79 + ll
  80 + end
  81 +
  82 + end
5 83
6 end 84 end
test/unit/geo_ref_test.rb 0 → 100644
  Diff comments   View file @bacb490
@@ -0,0 +1,62 @@ @@ -0,0 +1,62 @@
  1 +# -*- coding: utf-8 -*-
  2 +
  3 +require File.dirname(__FILE__) + '/../test_helper'
  4 +
  5 +class GeoRefTest < ActiveSupport::TestCase
  6 +
  7 + ll = {
  8 + salvador: [-12.9, -38.5],
  9 + rio_de_janeiro: [-22.9, -43.1],
  10 + new_york: [ 40.7, -74.0],
  11 + tokyo: [ 35.6, 139.6]
  12 + }
  13 +
  14 + should 'calculate the distance between lat,lng points' do
  15 + assert_equal 1215, Noosfero::GeoRef.dist(*(ll[:salvador]+ll[:rio_de_janeiro])).round
  16 + assert_equal 6998, Noosfero::GeoRef.dist(*(ll[:salvador]+ll[:new_york])).round
  17 + assert_equal 17503, Noosfero::GeoRef.dist(*(ll[:salvador]+ll[:tokyo])).round
  18 + end
  19 +
  20 + should 'calculate the distance between a lat,lng points and a profile' do
  21 + env = fast_create Environment, name: 'SomeSite'
  22 + @acme = Enterprise.create! environment: env, identifier: 'acme', name: 'ACME',
  23 + city: 'Salvador', state: 'Bahia', country: 'BR', lat: -12.9, lng: -38.5
  24 + def sql_dist_to(ll)
  25 + ActiveRecord::Base.connection.execute(
  26 + "SELECT #{Noosfero::GeoRef.sql_dist ll[0], ll[1]} as dist" +
  27 + " FROM profiles WHERE id = #{@acme.id};"
  28 + ).first['dist'].to_f.round
  29 + end
  30 + assert_equal 1215, sql_dist_to(ll[:rio_de_janeiro])
  31 + assert_equal 6998, sql_dist_to(ll[:new_york])
  32 + assert_equal 17503, sql_dist_to(ll[:tokyo])
  33 + end
  34 +
  35 + def round_ll(ll)
  36 + ll.map{|n| n.is_a?(Float) ? n.to_i : n }
  37 + end
  38 +
  39 + should 'get lat/lng from address' do
  40 + Rails.cache.clear
  41 + ll = Noosfero::GeoRef.location_to_georef 'Salvador, Bahia, BR'
  42 + assert_equal [-12, -38, :SUCCESS], round_ll(ll)
  43 + end
  44 +
  45 + should 'get and cache lat/lng from address' do
  46 + Rails.cache.clear
  47 + ll = Noosfero::GeoRef.location_to_georef 'Curitiba, Paraná, BR'
  48 + assert_equal [-25, -49, :SUCCESS], round_ll(ll)
  49 + ll = Noosfero::GeoRef.location_to_georef 'Curitiba, Paraná, BR'
  50 + assert_equal [-25, -49, :SUCCESS, :CACHE], round_ll(ll)
  51 + end
  52 +
  53 + should 'notify a non existent address' do
  54 + Rails.cache.clear
  55 + orig_env = ENV['RAILS_ENV']
  56 + ENV['RAILS_ENV'] = 'X' # cancel throw for test mode on process_rest_req.
  57 + ll = Noosfero::GeoRef.location_to_georef 'Nowhere, Nocountry, XYZ'
  58 + ENV['RAILS_ENV'] = orig_env # restore value to do not mess with other tests.
  59 + assert_equal [0, 0, :ZERO_RESULTS], round_ll(ll)
  60 + end
  61 +
  62 +end