Some node documentation

[rails.git] / app / models / node.rb

diff --git a/app/models/node.rb b/app/models/node.rb
index abf0c583e14a97ced1aed1cd69d8bd932a4beaaa..2a073f5428d4bd0ab32cea436c888963419a99b4 100644 (file)
--- a/app/models/node.rb
+++ b/app/models/node.rb
@@ -1,92 +1,105 @@
-class Node < ActiveRecord::Base
+# The node model represents a current existing node, that is, the latest version. Use OldNode for historical nodes.
+
+class Node < GeoRecord
   require 'xml/libxml'
+
   set_table_name 'current_nodes'
   
-
-  validates_numericality_of :latitude
-  validates_numericality_of :longitude
-  # FIXME validate lat and lon within the world
+  validates_presence_of :user_id, :timestamp
+  validates_inclusion_of :visible, :in => [ true, false ]
+  validates_numericality_of :latitude, :longitude
+  validate :validate_position
 
   has_many :old_nodes, :foreign_key => :id
+  has_many :way_nodes
   belongs_to :user
+ 
+  # Sanity check the latitude and longitude and add an error if it's broken
+  def validate_position
+    errors.add_to_base("Node is not in the world") unless in_world?
+  end
 
-  def self.from_xml(xml, create=false)
-    p = XML::Parser.new
-    p.string = xml
-    doc = p.parse
+  # Is this node withing -90 > latitude > 90 and -180 > longitude > 180>
+  # * returns true/false
+  def in_world?
+    return false if self.lat < -90 or self.lat > 90
+    return false if self.lon < -180 or self.lon > 180
+    return true
+  end
 
-    node = Node.new
+  # Read in xml as text and return it's Node object representation
+  def self.from_xml(xml, create=false)
+    begin
+      p = XML::Parser.new
+      p.string = xml
+      doc = p.parse
+  
+      node = Node.new
 
-    doc.find('//osm/node').each do |pt|
+      doc.find('//osm/node').each do |pt|
+        node.lat = pt['lat'].to_f
+        node.lon = pt['lon'].to_f
 
+        return nil unless node.in_world?
 
-      node.latitude = pt['lat'].to_f
-      node.longitude = pt['lon'].to_f
+        unless create
+          if pt['id'] != '0'
+            node.id = pt['id'].to_i
+          end
+        end
 
-      if node.latitude > 90 or node.latitude < -90 or node.longitude > 180 or node.longitude < -180
-        return nil
-      end
+        node.visible = pt['visible'] and pt['visible'] == 'true'
 
-      unless create
-        if pt['id'] != '0'
-          node.id = pt['id'].to_i
+        if create
+          node.timestamp = Time.now
+        else
+          if pt['timestamp']
+            node.timestamp = Time.parse(pt['timestamp'])
+          end
         end
-      end
 
-      node.visible = pt['visible'] and pt['visible'] == 'true'
+        tags = []
 
-      if create
-        node.timestamp = Time.now
-      else
-        if pt['timestamp']
-          node.timestamp = Time.parse(pt['timestamp'])
+        pt.find('tag').each do |tag|
+          tags << [tag['k'],tag['v']]
         end
-      end
-
-      tags = []
 
-      pt.find('tag').each do |tag|
-        tags << [tag['k'],tag['v']]
+        node.tags = Tags.join(tags)
       end
-
-      tags = tags.collect { |k,v| "#{k}=#{v}" }.join(';')
-      tags = '' if tags.nil?
-
-      node.tags = tags
-
+    rescue
+      node = nil
     end
+
     return node
   end
 
-  def save_with_history
-    begin
-      Node.transaction do
-        self.timestamp = Time.now
-        self.save
-        old_node = OldNode.from_node(self)
-        old_node.save
-      end
-      return true
-    rescue Exception => ex
-      return nil
+  # Save this node with the appropriate OldNode object to represent it's history.
+  def save_with_history!
+    Node.transaction do
+      self.timestamp = Time.now
+      self.save!
+      old_node = OldNode.from_node(self)
+      old_node.save!
     end
   end
 
+  # Turn this Node in to a complete OSM XML object with <osm> wrapper
   def to_xml
     doc = OSM::API.new.get_xml_doc
     doc.root << to_xml_node()
     return doc
   end
 
+  # Turn this Node in to an XML Node without the <osm> wrapper.
   def to_xml_node(user_display_name_cache = nil)
     el1 = XML::Node.new 'node'
     el1['id'] = self.id.to_s
-    el1['lat'] = self.latitude.to_s
-    el1['lon'] = self.longitude.to_s
+    el1['lat'] = self.lat.to_s
+    el1['lon'] = self.lon.to_s
 
     user_display_name_cache = {} if user_display_name_cache.nil?
 
-    if user_display_name_cache and user_display_name_cache[self.user_id]
+    if user_display_name_cache and user_display_name_cache.key?(self.user_id)
       # use the cache if available
     elsif self.user.data_public?
       user_display_name_cache[self.user_id] = self.user.display_name
@@ -96,25 +109,24 @@ class Node < ActiveRecord::Base
 
     el1['user'] = user_display_name_cache[self.user_id] unless user_display_name_cache[self.user_id].nil?
 
-    Node.split_tags(el1, self.tags)
+    Tags.split(self.tags) do |k,v|
+      el2 = XML::Node.new('tag')
+      el2['k'] = k.to_s
+      el2['v'] = v.to_s
+      el1 << el2
+    end
+
     el1['visible'] = self.visible.to_s
     el1['timestamp'] = self.timestamp.xmlschema
     return el1
   end
 
-  def self.split_tags(el, tags)
-    tags.split(';').each do |tag|
-      parts = tag.split('=')
-      key = ''
-      val = ''
-      key = parts[0].strip unless parts[0].nil?
-      val = parts[1].strip unless parts[1].nil?
-      if key != '' && val != ''
-        el2 = XML::Node.new('tag')
-        el2['k'] = key.to_s
-        el2['v'] = val.to_s
-        el << el2
-      end
+  # Return the node's tags as a Hash of keys and their values
+  def tags_as_hash
+    hash = {}
+    Tags.split(self.tags) do |k,v|
+      hash[k] = v
     end
+    hash
   end
 end