Merge remote-tracking branch 'upstream/pull/4748'

[rails.git] / lib / osm.rb

diff --git a/lib/osm.rb b/lib/osm.rb
index 5f31e31bf3f83f2b232cd1687c0c7b6657d19bff..65eab6907a00ff6008299f28d7d2beb8b674d78c 100644 (file)
--- a/lib/osm.rb
+++ b/lib/osm.rb
@@ -1,246 +1,418 @@
+# The OSM module provides support functions for OSM.

 module OSM
 module OSM

+  require "time"
+  require "rexml/parsers/sax2parser"
+  require "rexml/text"
+  require "xml/libxml"
+
+  # The base class for API Errors.
+  class APIError < RuntimeError
+    def initialize(message = "Generic API Error")
+      super(message)
+    end

 
 

-  # This piece of magic reads a GPX with SAX and spits out
-  # lat/lng and stuff
-  #
-  # This would print every latitude value:
-  #
-  # gpx = OSM::GPXImporter.new('somefile.gpx')
-  # gpx.points {|p| puts p['latitude']}
+    def status
+      :internal_server_error
+    end
+  end

 
 

-  require 'time'
-  require 'rexml/parsers/sax2parser'
-  require 'rexml/text'
-  require 'xml/libxml'
-  require 'RMagick'
+  # Raised when access is denied.
+  class APIAccessDenied < APIError
+    def initialize
+      super("Access denied")
+    end

 
 

-  class Mercator
-    include Math
+    def status
+      :forbidden
+    end
+  end

 
 

-    def initialize(lat, lon, degrees_per_pixel, width, height)
-      #init me with your centre lat/lon, the number of degrees per pixel and the size of your image
-      @clat = lat
-      @clon = lon
-      @degrees_per_pixel = degrees_per_pixel
-      @degrees_per_pixel = 0.0000000001 if @degrees_per_pixel < 0.0000000001
-      @width = width
-      @height = height
-      @dlon = width / 2 * @degrees_per_pixel
-      @dlat = height / 2 * @degrees_per_pixel  * cos(@clat * PI / 180)
+  # Raised when an API object is not found.
+  class APINotFoundError < APIError
+    def initialize
+      super("Object not found")
+    end

 
 

-      @tx = xsheet(@clon - @dlon)
-      @ty = ysheet(@clat - @dlat)
+    def status
+      :not_found
+    end
+  end

 
 

-      @bx = xsheet(@clon + @dlon)
-      @by = ysheet(@clat + @dlat)
+  # Raised when a precondition to an API action fails sanity check.
+  class APIPreconditionFailedError < APIError
+    def initialize(message = "")
+      super("Precondition failed: #{message}")
+    end

 
 

+    def status
+      :precondition_failed

     end
     end

+  end

 
 

-    #the following two functions will give you the x/y on the entire sheet
+  # Raised when to delete an already-deleted object.
+  class APIAlreadyDeletedError < APIError
+    def initialize(object = "object", object_id = "")
+      @object = object
+      @object_id = object_id

 
 

-    def kilometerinpixels
-      return 40008.0  / 360.0 * @degrees_per_pixel
+      super("The #{object} with the id #{object_id} has already been deleted")

     end
 
     end
 

-    def ysheet(lat)
-      log(tan(PI / 4 +  (lat  * PI / 180 / 2)))
+    attr_reader :object, :object_id
+
+    def status
+      :gone

     end
     end

+  end

 
 

-    def xsheet(lon)
-      lon
+  # Raised when the user logged in isn't the same as the changeset
+  class APIUserChangesetMismatchError < APIError
+    def initialize
+      super("The user doesn't own that changeset")

     end
 
     end
 

-    #and these two will give you the right points on your image. all the constants can be reduced to speed things up. FIXME
+    def status
+      :conflict
+    end
+  end

 
 

-    def y(lat)
-      return @height - ((ysheet(lat) - @ty) / (@by - @ty) * @height)
+  # Raised when the changeset provided is already closed
+  class APIChangesetAlreadyClosedError < APIError
+    def initialize(changeset)
+      @changeset = changeset
+
+      super("The changeset #{changeset.id} was closed at #{changeset.closed_at}")

     end
 
     end
 

-    def x(lon)
-      return  ((xsheet(lon) - @tx) / (@bx - @tx) * @width)
+    attr_reader :changeset
+
+    def status
+      :conflict

     end
   end
 
     end
   end
 

+  # Raised when the changeset provided is not yet closed
+  class APIChangesetNotYetClosedError < APIError
+    def initialize(changeset)
+      @changeset = changeset

 
 

-  class GPXImporter
-    # FIXME swap REXML for libXML
-    attr_reader :possible_points
-    attr_reader :actual_points
-    attr_reader :tracksegs
+      super("The changeset #{changeset.id} is not yet closed.")
+    end
+
+    attr_reader :changeset

 
 

-    def initialize(filename)
-      @filename = filename
+    def status
+      :conflict

     end
     end

+  end

 
 

-    def points
-      @possible_points = 0
-      @actual_points = 0
-      @tracksegs = 0
+  # Raised when a user is already subscribed to the changeset
+  class APIChangesetAlreadySubscribedError < APIError
+    def initialize(changeset)
+      @changeset = changeset

 
 

-      lat = -1
-      lon = -1
-      ele = -1
-      date = DateTime.now();
-      gotlatlon = false
-      gotele = false
-      gotdate = false
+      super("You are already subscribed to changeset #{changeset.id}.")
+    end

 
 

-      parser = REXML::Parsers::SAX2Parser.new(File.new(@filename))
+    attr_reader :changeset

 
 

-      parser.listen( :start_element,  %w{ trkpt }) do |uri,localname,qname,attributes| 
-        lat = attributes['lat'].to_f
-        lon = attributes['lon'].to_f
-        gotlatlon = true
-        @possible_points += 1
-      end
+    def status
+      :conflict
+    end
+  end

 
 

-      parser.listen( :characters, %w{ ele } ) do |text|
-        ele = text
-        gotele = true
-      end
+  # Raised when a user is not subscribed to the changeset
+  class APIChangesetNotSubscribedError < APIError
+    def initialize(changeset)
+      @changeset = changeset

 
 

-      parser.listen( :characters, %w{ time } ) do |text|
-        if text && text != ''
-          begin
-            date = DateTime.parse(text)
-            gotdate = true
-          rescue
-          end
-        end
-      end
+      super("You are not subscribed to changeset #{changeset.id}.")
+    end

 
 

-      parser.listen( :end_element, %w{ trkseg } ) do |uri, localname, qname|
-        @tracksegs += 1
-      end
+    attr_reader :changeset

 
 

-      parser.listen( :end_element, %w{ trkpt } ) do |uri,localname,qname|
-        if gotlatlon && gotdate
-          ele = '0' unless gotele
-          if lat < 90 && lat > -90 && lon > -180 && lon < 180
-            @actual_points += 1
-            yield Hash['latitude' => lat, 'longitude' => lon, 'timestamp' => date, 'altitude' => ele, 'segment' => @tracksegs]
-          end
-        end
-        gotlatlon = false
-        gotele = false
-        gotdate = false
-      end
+    def status
+      :not_found
+    end
+  end

 
 

-      parser.parse
+  # Raised when a change is expecting a changeset, but the changeset doesn't exist
+  class APIChangesetMissingError < APIError
+    def initialize
+      super("You need to supply a changeset to be able to make a change")

     end
 
     end
 

-    def get_picture(min_lat, min_lon, max_lat, max_lon, num_points)
-      #puts "getting picfor bbox #{min_lat},#{min_lon} - #{max_lat},#{max_lon}"
-      frames = 10
-      width = 250
-      height = 250
-      rat= Math.cos( ((max_lat + min_lat)/2.0) /  180.0 * 3.141592)
-      proj = OSM::Mercator.new((min_lat + max_lat) / 2, (max_lon + min_lon) / 2, (max_lat - min_lat) / width / rat, width, height)
+    def status
+      :conflict
+    end
+  end

 
 

-      images = []
+  # Raised when a diff is uploaded containing many changeset IDs which don't match
+  # the changeset ID that the diff was uploaded to.
+  class APIChangesetMismatchError < APIError
+    def initialize(provided, allowed)
+      super("Changeset mismatch: Provided #{provided} but only #{allowed} is allowed")
+    end

 
 

-      frames.times do
-        gc =  Magick::Draw.new
-        gc.stroke_linejoin('miter')
-        gc.stroke('#FFFFFF')
-        gc.fill('#FFFFFF')
-        gc.rectangle(0,0,width,height)
-        gc.stroke_width(1)
-        images << gc
-      end
+    def status
+      :conflict
+    end
+  end

 
 

-      oldpx = 0.0
-      oldpy = 0.0
-
-      first = true
-
-      m = 0
-      mm = 0
-      points do |p|
-        px = proj.x(p['longitude'])
-        py = proj.y(p['latitude'])
-        frames.times do |n|
-          images[n].stroke_width(1)
-          images[n].stroke('#BBBBBB')
-          images[n].fill('#BBBBBB')
-        #  puts "A #{px},#{py} - #{oldpx},#{oldpy}"
-          images[n].line(px, py, oldpx, oldpy ) unless first
-        end
-        images[mm].stroke_width(3)
-        images[mm].stroke('#000000')
-        images[mm].fill('#000000')
-        images[mm].line(px, py, oldpx, oldpy ) unless first
-      #  puts "B #{px},#{py} - #{oldpx},#{oldpy}"
-        m +=1
-        if m > num_points.to_f / frames.to_f * (mm+1)
-          mm += 1
-        end
-        first = false
-        oldpy = py
-        oldpx = px
-      end
+  # Raised when a diff upload has an unknown action. You can only have create,
+  # modify, or delete
+  class APIChangesetActionInvalid < APIError
+    def initialize(provided)
+      super("Unknown action #{provided}, choices are create, modify, delete")
+    end

 
 

-      il = Magick::ImageList.new
-
-      frames.times do |n|
-        canvas = Magick::Image.new(width, height) {
-          self.background_color = 'white'
-        }
-        begin
-          images[n].draw(canvas)
-        rescue ArgumentError
-        end
-        canvas.format = 'GIF'
-        il << canvas
-      end
+    def status
+      :bad_request
+    end
+  end
+
+  # Raised when bad XML is encountered which stops things parsing as
+  # they should.
+  class APIBadXMLError < APIError
+    def initialize(model, xml, message = "")
+      super("Cannot parse valid #{model} from xml string #{xml}. #{message}")
+    end
+
+    def status
+      :bad_request
+    end
+  end

 
 

-      il.delay = 50
-      il.format = 'GIF'
-      return il.to_blob
+  # Raised when the provided version is not equal to the latest in the db.
+  class APIVersionMismatchError < APIError
+    def initialize(id, type, provided, latest)
+      @id = id
+      @type = type
+      @provided = provided
+      @latest = latest
+
+      super("Version mismatch: Provided #{provided}, server had: #{latest} of #{type} #{id}")

     end
 
     end
 

-    def get_icon(min_lat, min_lon, max_lat, max_lon)
-      #puts "getting icon for bbox #{min_lat},#{min_lon} - #{max_lat},#{max_lon}"
-      width = 50
-      height = 50
-      rat= Math.cos( ((max_lat + min_lat)/2.0) /  180.0 * 3.141592)
-      proj = OSM::Mercator.new((min_lat + max_lat) / 2, (max_lon + min_lon) / 2, (max_lat - min_lat) / width / rat, width, height)
+    attr_reader :provided, :latest, :id, :type

 
 

-      images = []
+    def status
+      :conflict
+    end
+  end

 
 

-      gc =  Magick::Draw.new
-      gc.stroke_linejoin('miter')
+  # raised when a two tags have a duplicate key string in an element.
+  # this is now forbidden by the API.
+  class APIDuplicateTagsError < APIError
+    def initialize(type, id, tag_key)
+      @type = type
+      @id = id
+      @tag_key = tag_key

 
 

-      oldpx = 0.0
-      oldpy = 0.0
+      super("Element #{type}/#{id} has duplicate tags with key #{tag_key}")
+    end

 
 

-      first = true
+    attr_reader :type, :id, :tag_key

 
 

-      gc.stroke_width(1)
-      gc.stroke('#000000')
-      gc.fill('#000000')
+    def status
+      :bad_request
+    end
+  end

 
 

-      points do |p|
-        px = proj.x(p['longitude'])
-        py = proj.y(p['latitude'])
-        gc.line(px, py, oldpx, oldpy ) unless first
-       # puts "C #{px},#{py} - #{oldpx},#{oldpy}"
-        first = false
-        oldpy = py
-        oldpx = px
-      end
+  # Raised when a way has more than the configured number of way nodes.
+  # This prevents ways from being to long and difficult to work with
+  class APITooManyWayNodesError < APIError
+    def initialize(id, provided, max)
+      super("You tried to add #{provided} nodes to way #{id}, however only #{max} are allowed")

 
 

-      canvas = Magick::Image.new(width, height) {
-        self.background_color = 'white'
-      }
-      begin
-        gc.draw(canvas)
-      rescue ArgumentError
-      end
-      canvas.format = 'GIF'
-      return canvas.to_blob
+      @id = id
+      @provided = provided
+      @max = max
+    end
+
+    attr_reader :id, :provided, :max
+
+    def status
+      :bad_request
+    end
+  end
+
+  # Raised when a relation has more than the configured number of relation members.
+  # This prevents relations from being too complex and difficult to work with
+  class APITooManyRelationMembersError < APIError
+    def initialize(id, provided, max)
+      super("You tried to add #{provided} members to relation #{id}, however only #{max} are allowed")
+
+      @id = id
+      @provided = provided
+      @max = max
+    end
+
+    attr_reader :id, :provided, :max
+
+    def status
+      :bad_request
+    end
+  end
+
+  ##
+  # raised when user input couldn't be parsed
+  class APIBadUserInput < APIError
+    def status
+      :bad_request
+    end
+  end
+
+  ##
+  # raised when bounding box is invalid
+  class APIBadBoundingBox < APIError
+    def status
+      :bad_request
+    end
+  end
+
+  ##
+  # raised when an API call is made using a method not supported on that URI
+  class APIBadMethodError < APIError
+    def initialize(supported_method)
+      super("Only method #{supported_method} is supported on this URI")
+    end
+
+    def status
+      :method_not_allowed
+    end
+  end
+
+  ##
+  # raised when an API call takes too long
+  class APITimeoutError < APIError
+    def initialize
+      super("Request timed out")

     end
 
     end
 

+    def status
+      :request_timeout
+    end
+  end
+
+  ##
+  # raised when someone tries to redact a current version of
+  # an element - only historical versions can be redacted.
+  class APICannotRedactError < APIError
+    def initialize
+      super("Cannot redact current version of element, only historical versions may be redacted.")
+    end
+
+    def status
+      :bad_request
+    end
+  end
+
+  # Raised when the note provided is already closed
+  class APINoteAlreadyClosedError < APIError
+    def initialize(note)
+      @note = note
+
+      super("The note #{note.id} was closed at #{note.closed_at}")
+    end
+
+    attr_reader :note
+
+    def status
+      :conflict
+    end
+  end
+
+  # Raised when the note provided is already open
+  class APINoteAlreadyOpenError < APIError
+    def initialize(note)
+      @note = note
+
+      super("The note #{note.id} is already open")
+    end
+
+    attr_reader :note
+
+    def status
+      :conflict
+    end
+  end
+
+  # raised when a two preferences have a duplicate key string.
+  class APIDuplicatePreferenceError < APIError
+    def initialize(key)
+      @key = key
+
+      super("Duplicate preferences with key #{key}")
+    end
+
+    attr_reader :key
+
+    def status
+      :bad_request
+    end
+  end
+
+  # Raised when a rate limit is exceeded
+  class APIRateLimitExceeded < APIError
+    def initialize
+      super("Rate limit exceeded")
+    end
+
+    def status
+      :too_many_requests
+    end
+  end
+
+  # Helper methods for going to/from mercator and lat/lng.
+  class Mercator
+    include Math
+
+    # init me with your bounding box and the size of your image
+    def initialize(min_lat, min_lon, max_lat, max_lon, width, height)
+      xsize = xsheet(max_lon) - xsheet(min_lon)
+      ysize = ysheet(max_lat) - ysheet(min_lat)
+      xscale = xsize / width
+      yscale = ysize / height
+      scale = [xscale, yscale].max
+
+      xpad = (width * scale) - xsize
+      ypad = (height * scale) - ysize
+
+      @width = width
+      @height = height
+
+      @tx = xsheet(min_lon) - (xpad / 2)
+      @ty = ysheet(min_lat) - (ypad / 2)
+
+      @bx = xsheet(max_lon) + (xpad / 2)
+      @by = ysheet(max_lat) + (ypad / 2)
+    end
+
+    # the following two functions will give you the x/y on the entire sheet
+
+    def ysheet(lat)
+      log(tan((PI / 4) + (lat * PI / 180 / 2))) / (PI / 180)
+    end
+
+    def xsheet(lon)
+      lon
+    end
+
+    # and these two will give you the right points on your image. all the constants can be reduced to speed things up. FIXME
+    # If the bbox has no extent, return the centre of the image to avoid dividing by zero.
+
+    def y(lat)
+      return @height / 2 if (@by - @ty).zero?
+
+      @height - ((ysheet(lat) - @ty) / (@by - @ty) * @height)
+    end
+
+    def x(lon)
+      return @width / 2 if (@bx - @tx).zero?
+
+      ((xsheet(lon) - @tx) / (@bx - @tx) * @width)
+    end

   end
 
   class GreatCircle
   end
 
   class GreatCircle


@@ -256,139 +428,107 @@ module OSM
     def distance(lat, lon)
       lat = lat * PI / 180
       lon = lon * PI / 180
     def distance(lat, lon)
       lat = lat * PI / 180
       lon = lon * PI / 180

-      return 6372.795 * 2 * asin(sqrt(sin((lat - @lat) / 2) ** 2 + cos(@lat) * cos(lat) * sin((lon - @lon)/2) ** 2))
+      6372.795 * 2 * asin(sqrt((sin((lat - @lat) / 2)**2) + (cos(@lat) * cos(lat) * (sin((lon - @lon) / 2)**2))))

     end
 
     # get the worst case bounds for a given radius from the base position
     def bounds(radius)
     end
 
     # get the worst case bounds for a given radius from the base position
     def bounds(radius)

-      latradius = 2 * asin(sqrt(sin(radius / 6372.795 / 2) ** 2))
-      lonradius = 2 * asin(sqrt(sin(radius / 6372.795 / 2) ** 2 / cos(@lat) ** 2))
-      minlat = (@lat - latradius) * 180 / PI
-      maxlat = (@lat + latradius) * 180 / PI
-      minlon = (@lon - lonradius) * 180 / PI
-      maxlon = (@lon + lonradius) * 180 / PI
-      return { :minlat => minlat, :maxlat => maxlat, :minlon => minlon, :maxlon => maxlon }
-    end
-  end
-
-  class GeoRSS
-    def initialize(feed_title='OpenStreetMap GPS Traces', feed_description='OpenStreetMap GPS Traces', feed_url='http://www.openstreetmap.org/traces/')
-      @doc = XML::Document.new
-      @doc.encoding = 'UTF-8' 
-      
-      rss = XML::Node.new 'rss'
-      @doc.root = rss
-      rss['version'] = "2.0"
-      rss['xmlns:geo'] = "http://www.w3.org/2003/01/geo/wgs84_pos#"
-      @channel = XML::Node.new 'channel'
-      rss << @channel
-      title = XML::Node.new 'title'
-      title <<  feed_title
-      @channel << title
-      description_el = XML::Node.new 'description'
-      @channel << description_el
-
-      description_el << feed_description
-      link = XML::Node.new 'link'
-      link << feed_url
-      @channel << link
-      image = XML::Node.new 'image'
-      @channel << image
-      url = XML::Node.new 'url'
-      url << 'http://www.openstreetmap.org/feeds/mag_map-rss2.0.png'
-      image << url
-      title = XML::Node.new 'title'
-      title << "OpenStreetMap"
-      image << title
-      width = XML::Node.new 'width'
-      width << '100'
-      image << width
-      height = XML::Node.new 'height'
-      height << '100'
-      image << height
-      link = XML::Node.new 'link'
-      link << feed_url
-      image << link
-    end
-
-    def add(latitude=0, longitude=0, title_text='dummy title', author_text='anonymous', url='http://www.example.com/', description_text='dummy description', timestamp=DateTime.now)
-      item = XML::Node.new 'item'
-
-      title = XML::Node.new 'title'
-      item << title
-      title << title_text
-      link = XML::Node.new 'link'
-      link << url
-      item << link
-
-      guid = XML::Node.new 'guid'
-      guid << url
-      item << guid
-
-      description = XML::Node.new 'description'
-      description << description_text
-      item << description
-
-      author = XML::Node.new 'author'
-      author << author_text
-      item << author
-
-      pubDate = XML::Node.new 'pubDate'
-      pubDate << timestamp.to_s(:rfc822)
-      item << pubDate
-
-      if latitude
-        lat_el = XML::Node.new 'geo:lat'
-        lat_el << latitude.to_s
-        item << lat_el
-      end
+      latradius = 2 * asin(sqrt(sin(radius / 6372.795 / 2)**2))

 
 

-      if longitude
-        lon_el = XML::Node.new 'geo:long'
-        lon_el << longitude.to_s
-        item << lon_el
+      begin
+        lonradius = 2 * asin(sqrt((sin(radius / 6372.795 / 2)**2) / (cos(@lat)**2)))
+      rescue Errno::EDOM, Math::DomainError
+        lonradius = PI

       end
 
       end
 

-      @channel << item
+      minlat = [(@lat - latradius) * 180 / PI, -90].max
+      maxlat = [(@lat + latradius) * 180 / PI, 90].min
+      minlon = [(@lon - lonradius) * 180 / PI, -180].max
+      maxlon = [(@lon + lonradius) * 180 / PI, 180].min
+
+      BoundingBox.new(minlon, minlat, maxlon, maxlat)

     end
 
     end
 

-    def to_s
-      return @doc.to_s
+    # get the SQL to use to calculate distance
+    def sql_for_distance(lat_field, lon_field)
+      "6372.795 * 2 * asin(sqrt(power(sin((radians(#{lat_field}) - #{@lat}) / 2), 2) + cos(#{@lat}) * cos(radians(#{lat_field})) * power(sin((radians(#{lon_field}) - #{@lon})/2), 2)))"

     end
   end
 
   class API
     end
   end
 
   class API

-    def get_xml_doc
+    def xml_doc

       doc = XML::Document.new
       doc = XML::Document.new

-      doc.encoding = 'UTF-8' 
-      root = XML::Node.new 'osm'
-      root['version'] = API_VERSION
-      root['generator'] = 'OpenStreetMap server'
-      doc.root = root
-      return doc
-    end
-  end
-
-  def self.IPLocation(ip_address)
-    Timeout::timeout(4) do
-      Net::HTTP.start('api.hostip.info') do |http|
-        country = http.get("/country.php?ip=#{ip_address}").body
-        country = "GB" if country = "UK"
-        Net::HTTP.start('ws.geonames.org') do |http|
-          xml = REXML::Document.new(http.get("/countryInfo?country=#{country}").body)
-          xml.elements.each("geonames/country") do |ele|
-            minlon = ele.get_text("bBoxWest").to_s
-            minlat = ele.get_text("bBoxSouth").to_s
-            maxlon = ele.get_text("bBoxEast").to_s
-            maxlat = ele.get_text("bBoxNorth").to_s
-            return { :minlon => minlon, :minlat => minlat, :maxlon => maxlon, :maxlat => maxlat }
-          end
-        end
+      doc.encoding = XML::Encoding::UTF_8
+      root = XML::Node.new "osm"
+      xml_root_attributes.each do |k, v|
+        root[k] = v

       end
       end

+      doc.root = root
+      doc
+    end
+
+    def xml_root_attributes
+      { "version" => Settings.api_version,
+        "generator" => Settings.generator,
+        "copyright" => Settings.copyright_owner,
+        "attribution" => Settings.attribution_url,
+        "license" => Settings.license_url }

     end
     end

+  end
+
+  def self.ip_to_country(ip_address)
+    ipinfo = maxmind_database.lookup(ip_address) if Settings.key?(:maxmind_database)
+
+    return ipinfo.country.iso_code if ipinfo&.found?
+
+    nil
+  end
+
+  def self.ip_location(ip_address)
+    code = OSM.ip_to_country(ip_address)
+
+    if code && country = Country.find(code)
+      return { :minlon => country.min_lon, :minlat => country.min_lat, :maxlon => country.max_lon, :maxlat => country.max_lat }
+    end
+
+    nil
+  end
+
+  # Parse a float, raising a specified exception on failure
+  def self.parse_float(str, klass, *args)
+    Float(str)
+  rescue StandardError
+    raise klass.new(*args)
+  end
+
+  # Construct a random token of a given length
+  def self.make_token(length = 24)
+    SecureRandom.urlsafe_base64(length)
+  end
+
+  # Return an SQL fragment to select a given area of the globe
+  def self.sql_for_area(bbox, prefix = nil)
+    tilesql = QuadTile.sql_for_area(bbox, prefix)
+    bbox = bbox.to_scaled
+
+    "#{tilesql} AND #{prefix}latitude BETWEEN #{bbox.min_lat} AND #{bbox.max_lat} " \
+      "AND #{prefix}longitude BETWEEN #{bbox.min_lon} AND #{bbox.max_lon}"
+  end
+
+  # Return the terms and conditions text for a given country
+  def self.legal_text_for_country(country_code)
+    file_name = Rails.root.join("config", "legales", "#{country_code}.yml")
+    file_name = Rails.root.join("config", "legales", "#{Settings.default_legale}.yml") unless File.exist? file_name
+    YAML.load_file(file_name).transform_values!(&:html_safe)
+  end
+
+  # Return the HTTP client to use
+  def self.http_client
+    @http_client ||= Faraday.new(:request => { :timeout => 15 })
+  end

 
 

-    return nil
-  rescue Exception
-    return nil
+  # Return the MaxMindDB database handle
+  def self.maxmind_database
+    @maxmind_database ||= MaxMindDB.new(Settings.maxmind_database) if Settings.key?(:maxmind_database)

   end
 end
   end
 end