More work on optimisation the location of nearby users - it turns out

[rails.git] / lib / osm.rb

diff --git a/lib/osm.rb b/lib/osm.rb
index c223f05809d54319491713dbb69b2ae30d60bb68..789a5f4398b72dadb1a186e39f352155766638eb 100644 (file)
--- a/lib/osm.rb
+++ b/lib/osm.rb
@@ -1,244 +1,351 @@
+# The OSM module provides support functions for OSM.

 module OSM
 
 module OSM
 

-  # 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']}
-

   require 'time'
   require 'rexml/parsers/sax2parser'
   require 'rexml/text'
   require 'xml/libxml'
   require 'time'
   require 'rexml/parsers/sax2parser'
   require 'rexml/text'
   require 'xml/libxml'

+  require 'digest/md5'

   require 'RMagick'
 
   require 'RMagick'
 

-  class Mercator
-    include Math
+  # The base class for API Errors.
+  class APIError < RuntimeError
+    def status
+      :internal_server_error
+    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
-      @width = width
-      @height = height
-      @dlon = width / 2 * degrees_per_pixel
-      @dlat = height / 2 * degrees_per_pixel  * cos(@clat * PI / 180)
+    def to_s
+      "Generic API Error"
+    end
+  end

 
 

-      @tx = xsheet(@clon - @dlon)
-      @ty = ysheet(@clat - @dlat)
+  # Raised when an API object is not found.
+  class APINotFoundError < APIError
+    def status
+      :not_found
+    end

 
 

-      @bx = xsheet(@clon + @dlon)
-      @by = ysheet(@clat + @dlat)
+    def to_s
+      "Object not found"
+    end
+  end

 
 

+  # Raised when a precondition to an API action fails sanity check.
+  class APIPreconditionFailedError < APIError
+    def initialize(message = "")
+      @message = message

     end
 
     end
 

-    #the following two functions will give you the x/y on the entire sheet
+    def status
+      :precondition_failed    
+    end

 
 

-    def kilometerinpixels
-      return 40008.0  / 360.0 * @degrees_per_pixel
+    def to_s
+      "Precondition failed: #{@message}"

     end
     end

+  end

 
 

-    def ysheet(lat)
-      log(tan(PI / 4 +  (lat  * PI / 180 / 2)))
+  # Raised when to delete an already-deleted object.
+  class APIAlreadyDeletedError < APIError
+    def initialize(object = "object", object_id = "")
+      @object, @object_id = object, object_id

     end
     end

+    
+    attr_reader :object, :object_id

 
 

-    def xsheet(lon)
-      lon
+    def status
+      :gone
+    end
+    
+    def to_s
+      "The #{object} with the id #{object_id} has already been deleted"

     end
     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
+  # Raised when the user logged in isn't the same as the changeset
+  class APIUserChangesetMismatchError < APIError
+    def status
+      :conflict
+    end

 
 

-    def y(lat)
-      return @height - ((ysheet(lat) - @ty) / (@by - @ty) * @height)
+    def to_s
+      "The user doesn't own that changeset"

     end
     end

+  end

 
 

-    def x(lon)
-      return  ((xsheet(lon) - @tx) / (@bx - @tx) * @width)
+  # Raised when the changeset provided is already closed
+  class APIChangesetAlreadyClosedError < APIError
+    def initialize(changeset)
+      @changeset = changeset
+    end
+
+    attr_reader :changeset
+
+    def status
+      :conflict
+    end
+
+    def to_s
+      "The changeset #{@changeset.id} was closed at #{@changeset.closed_at}"

     end
   end
     end
   end

+  
+  # Raised when a change is expecting a changeset, but the changeset doesn't exist
+  class APIChangesetMissingError < APIError
+    def status
+      :conflict
+    end

 
 

+    def to_s
+      "You need to supply a changeset to be able to make a change"
+    end
+  end

 
 

-  class GPXImporter
-    # FIXME swap REXML for libXML
-    attr_reader :possible_points
-    attr_reader :actual_points
-    attr_reader :tracksegs
-
-    def initialize(filename)
-      @filename = filename
-      @possible_points = 0
-      @actual_points = 0
-      @tracksegs = 0
-    end
-
-    def points
-      file = File.new(@filename)
-      parser = REXML::Parsers::SAX2Parser.new( file )
-
-      lat = -1
-      lon = -1
-      ele = -1
-      date = Time.now();
-      gotlatlon = false
-      gotele = false
-      gotdate = false
-
-      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
+  # 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)
+      @provided, @allowed = provided, allowed
+    end

 
 

-      parser.listen( :characters, %w{ ele } ) do |text|
-        ele = text
-        gotele = true
-      end
+    def status
+      :conflict
+    end

 
 

-      parser.listen( :characters, %w{ time } ) do |text|
-        if text && text != ''
-          date = Time.parse(text)
-          gotdate = true
-        end
-      end
+    def to_s
+      "Changeset mismatch: Provided #{@provided} but only #{@allowed} is allowed"
+    end
+  end
+  
+  # Raised when a diff upload has an unknown action. You can only have create,
+  # modify, or delete
+  class APIChangesetActionInvalid < APIError
+    def initialize(provided)
+      @provided = provided
+    end

 
 

-      parser.listen( :end_element, %w{ trkseg } ) do |uri, localname, qname|
-        @tracksegs += 1
-      end
+    def status
+      :bad_request
+    end
+    
+    def to_s
+      "Unknown action #{@provided}, choices are create, modify, delete"
+    end
+  end

 
 

-      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
-      parser.parse
-    end
-
-    def get_picture(min_lat, min_lon, max_lat, max_lon, num_points)
-      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)
-
-      images = []
-
-      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
+  # Raised when bad XML is encountered which stops things parsing as
+  # they should.
+  class APIBadXMLError < APIError
+    def initialize(model, xml, message="")
+      @model, @xml, @message = model, xml, message
+    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')
-          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
-
-        m +=1
-        if m > num_points.to_f / frames.to_f * (mm+1)
-          mm += 1
-        end
-        first = false
-        oldpy = py
-        oldpx = px
-      end
+    def status
+      :bad_request
+    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 to_s
+      "Cannot parse valid #{@model} from xml string #{@xml}. #{@message}"
+    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, @type, @provided, @latest = id, type, provided, latest

     end
 
     end
 

-    def get_icon(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

 
 

-      gc =  Magick::Draw.new
-      gc.stroke_linejoin('miter')
+    def to_s
+      "Version mismatch: Provided #{provided}, server had: #{latest} of #{type} #{id}"
+    end
+  end

 
 

-      oldpx = 0.0
-      oldpy = 0.0
+  # 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, @id, @tag_key = type, id, 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

 
 

-      points do |p|
-        px = proj.x(p['longitude'])
-        py = proj.y(p['latitude'])
-        gc.line(px, py, oldpx, oldpy ) unless first
-        first = false
-        oldpy = py
-        oldpx = px
-      end
+    def to_s
+      "Element #{@type}/#{@id} has duplicate tags with key #{@tag_key}"
+    end
+  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(provided, max)
+      @provided, @max = provided, max
+    end
+    
+    attr_reader :provided, :max

 
 

-      canvas = Magick::Image.new(width, height) {
-        self.background_color = 'white'
-      }
-      begin
-        gc.draw(canvas)
-      rescue ArgumentError
-      end
-      canvas.format = 'GIF'
-      return canvas.to_blob
+    def status
+      :bad_request
+    end
+    
+    def to_s
+      "You tried to add #{provided} nodes to the way, however only #{max} are allowed"
+    end
+  end
+
+  ##
+  # raised when user input couldn't be parsed
+  class APIBadUserInput < APIError
+    def initialize(message)
+      @message = message
+    end
+
+    def status
+      :bad_request
+    end
+
+    def to_s
+      @message
+    end
+  end
+
+  ##
+  # raised when bounding box is invalid
+  class APIBadBoundingBox < APIError
+    def initialize(message)
+      @message = message
+    end
+
+    def status
+      :bad_request
+    end
+
+    def to_s
+      @message
+    end
+  end
+
+  ##
+  # raised when an API call is made using a method not supported on that URI
+  class APIBadMethodError < APIError
+    def initialize(supported_method)
+      @supported_method = supported_method
+    end
+
+    def status
+      :method_not_allowed

     end
 
     end
 

+    def to_s
+      "Only method #{@supported_method} is supported on this URI"
+    end
+  end
+
+  ##
+  # raised when an API call takes too long
+  class APITimeoutError < APIError
+    def status
+      :request_timeout
+    end
+
+    def to_s
+      "Request timed out"
+    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
+
+    def y(lat)
+      return @height - ((ysheet(lat) - @ty) / (@by - @ty) * @height)
+    end
+
+    def x(lon)
+      return  ((xsheet(lon) - @tx) / (@bx - @tx) * @width)
+    end
+  end
+
+  class GreatCircle
+    include Math
+
+    # initialise with a base position
+    def initialize(lat, lon)
+      @lat = lat * PI / 180
+      @lon = lon * PI / 180
+    end
+
+    # get the distance from the base position to a given position
+    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))
+    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
+
+    # 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 GeoRSS
   end
 
   class GeoRSS

-    def initialize(description='OpenStreetMap GPS Traces')
+    def initialize(feed_title='OpenStreetMap GPS Traces', feed_description='OpenStreetMap GPS Traces', feed_url='http://www.openstreetmap.org/traces/')

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

-      @doc.encoding = 'UTF-8' 
-      
+      @doc.encoding = XML::Encoding::UTF_8
+

       rss = XML::Node.new 'rss'
       @doc.root = rss
       rss['version'] = "2.0"
       rss = XML::Node.new 'rss'
       @doc.root = rss
       rss['version'] = "2.0"


@@ -246,19 +353,19 @@ module OSM
       @channel = XML::Node.new 'channel'
       rss << @channel
       title = XML::Node.new 'title'
       @channel = XML::Node.new 'channel'
       rss << @channel
       title = XML::Node.new 'title'

-      title <<  'OpenStreetMap GPS Traces'
+      title <<  feed_title

       @channel << title
       description_el = XML::Node.new 'description'
       @channel << description_el
 
       @channel << title
       description_el = XML::Node.new 'description'
       @channel << description_el
 

-      description_el << description
+      description_el << feed_description

       link = XML::Node.new 'link'
       link = XML::Node.new 'link'

-      link << 'http://www.openstreetmap.org/traces/'
+      link << feed_url

       @channel << link
       image = XML::Node.new 'image'
       @channel << image
       url = XML::Node.new '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'
+      url << 'http://www.openstreetmap.org/images/mag_map-rss2.0.png'

       image << url
       title = XML::Node.new 'title'
       title << "OpenStreetMap"
       image << url
       title = XML::Node.new 'title'
       title << "OpenStreetMap"


@@ -270,11 +377,11 @@ module OSM
       height << '100'
       image << height
       link = XML::Node.new 'link'
       height << '100'
       image << height
       link = XML::Node.new 'link'

-      link << 'http://www.openstreetmap.org/traces/'
+      link << feed_url

       image << link
     end
 
       image << link
     end
 

-    def add(latitude=0, longitude=0, title_text='dummy title', url='http://www.example.com/', description_text='dummy description', timestamp=Time.now)
+    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 = XML::Node.new 'item'
 
       title = XML::Node.new 'title'


@@ -284,21 +391,33 @@ module OSM
       link << url
       item << link
 
       link << url
       item << link
 

+      guid = XML::Node.new 'guid'
+      guid << url
+      item << guid
+

       description = XML::Node.new 'description'
       description << description_text
       item << description
 
       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 = XML::Node.new 'pubDate'

-      pubDate << timestamp.xmlschema
+      pubDate << timestamp.to_s(:rfc822)

       item << pubDate
 
       item << pubDate
 

-      lat_el = XML::Node.new 'geo:lat'
-      lat_el << latitude.to_s
-      item << lat_el
+      if latitude
+        lat_el = XML::Node.new 'geo:lat'
+        lat_el << latitude.to_s
+        item << lat_el
+      end

 
 

-      lon_el = XML::Node.new 'geo:lon'
-      lon_el << longitude.to_s
-      item << lon_el
+      if longitude
+        lon_el = XML::Node.new 'geo:long'
+        lon_el << longitude.to_s
+        item << lon_el
+      end

 
       @channel << item
     end
 
       @channel << item
     end


@@ -307,4 +426,62 @@ module OSM
       return @doc.to_s
     end
   end
       return @doc.to_s
     end
   end

+
+  class API
+    def get_xml_doc
+      doc = XML::Document.new
+      doc.encoding = XML::Encoding::UTF_8
+      root = XML::Node.new 'osm'
+      root['version'] = API_VERSION
+      root['generator'] = GENERATOR
+      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"
+        country = Country.find_by_code(country)
+        return { :minlon => country.min_lon, :minlat => country.min_lat, :maxlon => country.max_lon, :maxlat => country.max_lat }
+      end
+    end
+
+    return nil
+  rescue Exception
+    return nil
+  end
+
+  # Construct a random token of a given length
+  def self.make_token(length = 30)
+    chars = 'abcdefghijklmnopqrtuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'
+    token = ''
+
+    length.times do
+      token += chars[(rand * chars.length).to_i].chr
+    end
+
+    return token
+  end
+
+  # Return an encrypted version of a password
+  def self.encrypt_password(password, salt)
+    return Digest::MD5.hexdigest(password) if salt.nil?
+    return Digest::MD5.hexdigest(salt + password)
+  end
+
+  # Return an SQL fragment to select a given area of the globe
+  def self.sql_for_area(minlat, minlon, maxlat, maxlon, prefix = nil)
+    tilesql = QuadTile.sql_for_area(minlat, minlon, maxlat, maxlon, prefix)
+    minlat = (minlat * 10000000).round
+    minlon = (minlon * 10000000).round
+    maxlat = (maxlat * 10000000).round
+    maxlon = (maxlon * 10000000).round
+
+    return "#{tilesql} AND #{prefix}latitude BETWEEN #{minlat} AND #{maxlat} AND #{prefix}longitude BETWEEN #{minlon} AND #{maxlon}"
+  end
+
+

 end
 end