initial untest nginx config. API 0.6 tweaking still required.

[rails.git] / app / controllers / amf_controller.rb

diff --git a/app/controllers/amf_controller.rb b/app/controllers/amf_controller.rb
index 7f85280b79d29d5b320460d01f028f14727a3fd0..b0b3f13cf6c1947914caa7583e3fef58ff4bc392 100644 (file)
--- a/app/controllers/amf_controller.rb
+++ b/app/controllers/amf_controller.rb
@@ -3,7 +3,7 @@
 # OSM database takes place using this controller. Messages are 
 # encoded in the Actionscript Message Format (AMF).
 #
 # OSM database takes place using this controller. Messages are 
 # encoded in the Actionscript Message Format (AMF).
 #

-# Helper functions are in /lib/potlatch.
+# Helper functions are in /lib/potlatch.rb

 #
 # Author::     editions Systeme D / Richard Fairhurst 2004-2008
 # Licence::    public domain.
 #
 # Author::     editions Systeme D / Richard Fairhurst 2004-2008
 # Licence::    public domain.


@@ -14,6 +14,12 @@
 # from the AMF message), each method generally takes arguments in the order 
 # they were sent by the Potlatch SWF. Do not assume typing has been preserved. 
 # Methods all return an array to the SWF.
 # from the AMF message), each method generally takes arguments in the order 
 # they were sent by the Potlatch SWF. Do not assume typing has been preserved. 
 # Methods all return an array to the SWF.

+#
+# == API 0.6
+#
+# Note that this requires a patched version of composite_primary_keys 1.1.0
+# (see http://groups.google.com/group/compositekeys/t/a00e7562b677e193) 
+# if you are to run with POTLATCH_USE_SQL=false .

 # 
 # == Debugging
 # 
 # 
 # == Debugging
 # 


@@ -21,13 +27,19 @@
 #      return(-1,"message")            <-- just puts up a dialogue
 #      return(-2,"message")            <-- also asks the user to e-mail me
 # 
 #      return(-1,"message")            <-- just puts up a dialogue
 #      return(-2,"message")            <-- also asks the user to e-mail me
 # 

-# To write to the Rails log, use RAILS_DEFAULT_LOGGER.info("message").
+# To write to the Rails log, use logger.info("message").
+
+# Remaining issues:
+# * version conflict when POIs and ways are reverted

 
 class AmfController < ApplicationController
   require 'stringio'
 
   include Potlatch
 
 
 class AmfController < ApplicationController
   require 'stringio'
 
   include Potlatch
 

+  # Help methods for checking boundary sanity and area size
+  include MapBoundary
+

   session :off
   before_filter :check_api_writable
 
   session :off
   before_filter :check_api_writable
 


@@ -36,235 +48,403 @@ class AmfController < ApplicationController
   # ** FIXME: refactor to reduce duplication of code across read/write
   
   def amf_read
   # ** FIXME: refactor to reduce duplication of code across read/write
   
   def amf_read

-       req=StringIO.new(request.raw_post+0.chr)# Get POST data as request
-                                                                                       # (cf http://www.ruby-forum.com/topic/122163)
-       req.read(2)                                                             # Skip version indicator and client ID
-       results={}                                                              # Results of each body
+    req=StringIO.new(request.raw_post+0.chr)# Get POST data as request
+                              # (cf http://www.ruby-forum.com/topic/122163)
+    req.read(2)                                                                # Skip version indicator and client ID
+    results={}                                                         # Results of each body

 
 

-       # Parse request
+    # Parse request

 
        headers=AMF.getint(req)                                 # Read number of headers
 
 
        headers=AMF.getint(req)                                 # Read number of headers
 

-       headers.times do                                                # Read each header
-         name=AMF.getstring(req)                               #  |
-         req.getc                                                              #  | skip boolean
-         value=AMF.getvalue(req)                               #  |
-         header["name"]=value                                  #  |
-       end
-
-       bodies=AMF.getint(req)                                  # Read number of bodies
-       bodies.times do                                                 # Read each body
-         message=AMF.getstring(req)                    #  | get message name
-         index=AMF.getstring(req)                              #  | get index in response sequence
-         bytes=AMF.getlong(req)                                #  | get total size in bytes
-         args=AMF.getvalue(req)                                #  | get response (probably an array)
-
-         case message
-               when 'getpresets';                      results[index]=AMF.putdata(index,getpresets())
-               when 'whichways';                       results[index]=AMF.putdata(index,whichways(*args))
-               when 'whichways_deleted';       results[index]=AMF.putdata(index,whichways_deleted(*args))
-               when 'getway';                          results[index]=AMF.putdata(index,getway(args[0].to_i))
-               when 'getrelation';                     results[index]=AMF.putdata(index,getrelation(args[0].to_i))
-               when 'getway_old';                      results[index]=AMF.putdata(index,getway_old(args[0].to_i,args[1].to_i))
-               when 'getway_history';          results[index]=AMF.putdata(index,getway_history(args[0].to_i))
-               when 'getnode_history';         results[index]=AMF.putdata(index,getnode_history(args[0].to_i))
-               when 'findrelations';           results[index]=AMF.putdata(index,findrelations(*args))
-               when 'getpoi';                          results[index]=AMF.putdata(index,getpoi(*args))
-         end
-       end
+    headers.times do                                           # Read each header
+      name=AMF.getstring(req)                          #  |
+      req.getc                                                         #  | skip boolean
+      value=AMF.getvalue(req)                          #  |
+      header["name"]=value                                     #  |
+    end
+
+    bodies=AMF.getint(req)                                     # Read number of bodies
+    bodies.times do                                                    # Read each body
+      message=AMF.getstring(req)                       #  | get message name
+      index=AMF.getstring(req)                         #  | get index in response sequence
+      bytes=AMF.getlong(req)                           #  | get total size in bytes
+      args=AMF.getvalue(req)                           #  | get response (probably an array)
+      logger.info("Executing AMF #{message}:#{index}")
+
+      case message
+        when 'getpresets';                     results[index]=AMF.putdata(index,getpresets())
+        when 'whichways';                      results[index]=AMF.putdata(index,whichways(*args))
+        when 'whichways_deleted';      results[index]=AMF.putdata(index,whichways_deleted(*args))
+        when 'getway';                         results[index]=AMF.putdata(index,getway(args[0].to_i))
+        when 'getrelation';                    results[index]=AMF.putdata(index,getrelation(args[0].to_i))
+        when 'getway_old';                     results[index]=AMF.putdata(index,getway_old(args[0].to_i,args[1]))
+        when 'getway_history';         results[index]=AMF.putdata(index,getway_history(args[0].to_i))
+        when 'getnode_history';                results[index]=AMF.putdata(index,getnode_history(args[0].to_i))
+        when 'findgpx';                                results[index]=AMF.putdata(index,findgpx(*args))
+        when 'findrelations';          results[index]=AMF.putdata(index,findrelations(*args))
+        when 'getpoi';                         results[index]=AMF.putdata(index,getpoi(*args))
+      end
+    end
+    logger.info("encoding AMF results")

     sendresponse(results)
   end
 
   def amf_write
     sendresponse(results)
   end
 
   def amf_write

-       req=StringIO.new(request.raw_post+0.chr)
-       req.read(2)
-       results={}
-       renumberednodes={}                                              # Shared across repeated putways
-       renumberedways={}                                               # Shared across repeated putways
-
-       headers=AMF.getint(req)                                 # Read number of headers
-       headers.times do                                                # Read each header
-         name=AMF.getstring(req)                               #  |
-         req.getc                                                              #  | skip boolean
-         value=AMF.getvalue(req)                               #  |
-         header["name"]=value                                  #  |
-       end
-
-       bodies=AMF.getint(req)                                  # Read number of bodies
-       bodies.times do                                                 # Read each body
-         message=AMF.getstring(req)                    #  | get message name
-         index=AMF.getstring(req)                              #  | get index in response sequence
-         bytes=AMF.getlong(req)                                #  | get total size in bytes
-         args=AMF.getvalue(req)                                #  | get response (probably an array)
-
-         case message
-               when 'putway';                          r=putway(renumberednodes,*args)
+    req=StringIO.new(request.raw_post+0.chr)
+    req.read(2)
+    results={}
+    renumberednodes={}                                         # Shared across repeated putways
+    renumberedways={}                                          # Shared across repeated putways
+
+    headers=AMF.getint(req)                                    # Read number of headers
+    headers.times do                                           # Read each header
+      name=AMF.getstring(req)                          #  |
+      req.getc                                                         #  | skip boolean
+      value=AMF.getvalue(req)                          #  |
+      header["name"]=value                                     #  |
+    end
+
+    bodies=AMF.getint(req)                                     # Read number of bodies
+    bodies.times do                                                    # Read each body
+      message=AMF.getstring(req)                       #  | get message name
+      index=AMF.getstring(req)                         #  | get index in response sequence
+      bytes=AMF.getlong(req)                           #  | get total size in bytes
+      args=AMF.getvalue(req)                           #  | get response (probably an array)
+
+      logger.info("Executing AMF #{message}:#{index}")
+      case message
+        when 'putway';                         r=putway(renumberednodes,*args)

                                                                        renumberednodes=r[3]
                                                                        renumberednodes=r[3]

-                                                                       if r[1] != r[2]
-                                                                         renumberedways[r[1]] = r[2]
-                                                                       end
+                                                                       if r[1] != r[2] then renumberedways[r[1]] = r[2] end

                                                                        results[index]=AMF.putdata(index,r)
                                                                        results[index]=AMF.putdata(index,r)

-               when 'putrelation';                     results[index]=AMF.putdata(index,putrelation(renumberednodes, renumberedways, *args))
-               when 'deleteway';                       results[index]=AMF.putdata(index,deleteway(args[0],args[1].to_i))
-               when 'putpoi';                          results[index]=AMF.putdata(index,putpoi(*args))
-         end
-       end
+        when 'putrelation';                    results[index]=AMF.putdata(index,putrelation(renumberednodes, renumberedways, *args))
+        when 'deleteway';                      results[index]=AMF.putdata(index,deleteway(*args))
+        when 'putpoi';                         r=putpoi(*args)
+                                                                       if r[1] != r[2] then renumberednodes[r[1]] = r[2] end
+                                                               results[index]=AMF.putdata(index,r)
+        when 'startchangeset';         results[index]=AMF.putdata(index,startchangeset(*args))
+      end
+    end
+    logger.info("encoding AMF results")

     sendresponse(results)
   end
 
   private
 
     sendresponse(results)
   end
 
   private
 

+  # Start new changeset
+  
+  def startchangeset(usertoken, cstags, closeid, closecomment)
+    user = getuser(usertoken)
+    if !user then return -1,"You are not logged in, so Potlatch can't write any changes to the database." end
+
+    # close previous changeset and add comment
+    if closeid
+      cs = Changeset.find(closeid)
+      cs.set_closed_time_now
+      if cs.user_id!=user.id
+        return -2,"You cannot close that changeset because you're not the person who opened it."
+      elsif closecomment.empty?
+        cs.save!
+      else
+        cs.tags['comment']=closecomment
+        cs.save_with_tags!
+      end
+    end
+       
+    # open a new changeset
+    cs = Changeset.new
+    cs.tags = cstags
+    cs.user_id = user.id
+    # smsm1 doesn't like the next two lines and thinks they need to be abstracted to the model more/better
+    cs.created_at = Time.now.getutc
+    cs.closed_at = cs.created_at + Changeset::IDLE_TIMEOUT
+    cs.save_with_tags!
+    return [0,cs.id]
+  end
+

   # Return presets (default tags, localisation etc.):
   # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.
 
   def getpresets() #:doc:
   # Return presets (default tags, localisation etc.):
   # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.
 
   def getpresets() #:doc:

-       return POTLATCH_PRESETS
+    return POTLATCH_PRESETS

   end
 
   end
 

+  ##

   # Find all the ways, POI nodes (i.e. not part of ways), and relations
   # in a given bounding box. Nodes are returned in full; ways and relations 
   # are IDs only. 
   # Find all the ways, POI nodes (i.e. not part of ways), and relations
   # in a given bounding box. Nodes are returned in full; ways and relations 
   # are IDs only. 

-
+  #
+  # return is of the form: 
+  # [error_code, 
+  #  [[way_id, way_version], ...],
+  #  [[node_id, lat, lon, [tags, ...], node_version], ...],
+  #  [[rel_id, rel_version], ...]]
+  # where the ways are any visible ways which refer to any visible
+  # nodes in the bbox, nodes are any visible nodes in the bbox but not
+  # used in any way, rel is any relation which refers to either a way
+  # or node that we're returning.

   def whichways(xmin, ymin, xmax, ymax) #:doc:
   def whichways(xmin, ymin, xmax, ymax) #:doc:

-       enlarge = [(xmax-xmin)/8,0.01].min
-       xmin -= enlarge; ymin -= enlarge
-       xmax += enlarge; ymax += enlarge
-
-       if POTLATCH_USE_SQL then
-         way_ids = sql_find_way_ids_in_area(xmin, ymin, xmax, ymax)
-         points = sql_find_pois_in_area(xmin, ymin, xmax, ymax)
-         relation_ids = sql_find_relations_in_area_and_ways(xmin, ymin, xmax, ymax, way_ids)
-       else
-         # find the way ids in an area
-         nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => "current_nodes.visible = 1", :include => :ways)
-         way_ids = nodes_in_area.collect { |node| node.way_ids }.flatten.uniq
-
-         # find the node ids in an area that aren't part of ways
-         nodes_not_used_in_area = nodes_in_area.select { |node| node.ways.empty? }
-         points = nodes_not_used_in_area.collect { |n| [n.id, n.lon, n.lat, n.tags_as_hash] }
-
-         # find the relations used by those nodes and ways
-         relations = Relation.find_for_nodes(nodes_in_area.collect { |n| n.id }, :conditions => "visible = 1") +
-                  Relation.find_for_ways(way_ids, :conditions => "visible = 1")
-         relation_ids = relations.collect { |relation| relation.id }.uniq
-       end
-
-       [way_ids, points, relation_ids]
+    enlarge = [(xmax-xmin)/8,0.01].min
+    xmin -= enlarge; ymin -= enlarge
+    xmax += enlarge; ymax += enlarge
+    
+    # check boundary is sane and area within defined
+    # see /config/application.yml
+    check_boundaries(xmin, ymin, xmax, ymax)
+
+    if POTLATCH_USE_SQL then
+      ways = sql_find_ways_in_area(xmin, ymin, xmax, ymax)
+      points = sql_find_pois_in_area(xmin, ymin, xmax, ymax)
+      relations = sql_find_relations_in_area_and_ways(xmin, ymin, xmax, ymax, ways.collect {|x| x[0]})
+    else
+      # find the way ids in an area
+      nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => ["current_nodes.visible = ?", true], :include => :ways)
+      ways = nodes_in_area.inject([]) { |sum, node| 
+        visible_ways = node.ways.select { |w| w.visible? }
+        sum + visible_ways.collect { |w| [w.id,w.version] }
+      }.uniq
+      ways.delete([])
+
+      # find the node ids in an area that aren't part of ways
+      nodes_not_used_in_area = nodes_in_area.select { |node| node.ways.empty? }
+      points = nodes_not_used_in_area.collect { |n| [n.id, n.lon, n.lat, n.tags, n.version] }.uniq
+
+      # find the relations used by those nodes and ways
+      relations = Relation.find_for_nodes(nodes_in_area.collect { |n| n.id }, :conditions => {:visible => true}) +
+                  Relation.find_for_ways(ways.collect { |w| w[0] }, :conditions => {:visible => true})
+      relations = relations.collect { |relation| [relation.id,relation.version] }.uniq
+    end
+
+    [0, ways, points, relations]
+
+  rescue Exception => err
+    [-2,"Sorry - I can't get the map for that area."]

   end
 
   # Find deleted ways in current bounding box (similar to whichways, but ways
   # with a deleted node only - not POIs or relations).
 
   def whichways_deleted(xmin, ymin, xmax, ymax) #:doc:
   end
 
   # Find deleted ways in current bounding box (similar to whichways, but ways
   # with a deleted node only - not POIs or relations).
 
   def whichways_deleted(xmin, ymin, xmax, ymax) #:doc:

-       xmin -= 0.01; ymin -= 0.01
-       xmax += 0.01; ymax += 0.01
-
-       nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => "current_nodes.visible = 0 AND current_ways.visible = 0", :include => :ways_via_history)
-       way_ids = nodes_in_area.collect { |node| node.ways_via_history_ids }.flatten.uniq
-
-       [way_ids]
+    enlarge = [(xmax-xmin)/8,0.01].min
+    xmin -= enlarge; ymin -= enlarge
+    xmax += enlarge; ymax += enlarge
+
+    # check boundary is sane and area within defined
+    # see /config/application.yml
+    begin
+      check_boundaries(xmin, ymin, xmax, ymax)
+    rescue Exception => err
+      return [-2,"Sorry - I can't get the map for that area."]
+    end
+
+    nodes_in_area = Node.find_by_area(ymin, xmin, ymax, xmax, :conditions => ["current_ways.visible = ?", false], :include => :ways_via_history)
+    way_ids = nodes_in_area.collect { |node| node.ways_via_history_ids }.flatten.uniq
+
+    [0,way_ids]

   end
 
   # Get a way including nodes and tags.
   end
 
   # Get a way including nodes and tags.

-  # Returns 0 (success), a Potlatch-style array of points, and a hash of tags.
+  # Returns the way id, a Potlatch-style array of points, a hash of tags, and the version number.

 
   def getway(wayid) #:doc:
 
   def getway(wayid) #:doc:

-       if POTLATCH_USE_SQL then
-         points = sql_get_nodes_in_way(wayid)
-         tags = sql_get_tags_in_way(wayid)
-       else
-         # Ideally we would do ":include => :nodes" here but if we do that
-         # then rails only seems to return the first copy of a node when a
-         # way includes a node more than once
-         way = Way.find(wayid)
-         points = way.nodes.collect do |node|
-               nodetags=node.tags_as_hash
-               nodetags.delete('created_by')
-               [node.lon, node.lat, node.id, nodetags]
-         end
-         tags = way.tags
-       end
-
-       [wayid, points, tags]
+    if POTLATCH_USE_SQL then
+        points = sql_get_nodes_in_way(wayid)
+        tags = sql_get_tags_in_way(wayid)
+        version = sql_get_way_version(wayid)
+      else
+        # Ideally we would do ":include => :nodes" here but if we do that
+        # then rails only seems to return the first copy of a node when a
+        # way includes a node more than once
+        begin
+          way = Way.find(wayid)
+        rescue ActiveRecord::RecordNotFound
+          return [wayid,[],{}]
+        end
+
+        # check case where way has been deleted or doesn't exist
+        return [wayid,[],{}] if way.nil? or !way.visible
+
+        points = way.nodes.collect do |node|
+        nodetags=node.tags
+        nodetags.delete('created_by')
+        [node.lon, node.lat, node.id, nodetags, node.version]
+      end
+      tags = way.tags
+      version = way.version
+    end
+
+    [wayid, points, tags, version]

   end
   end

-
+  

   # Get an old version of a way, and all constituent nodes.
   #
   # Get an old version of a way, and all constituent nodes.
   #

-  # For undelete (version=0), always uses the most recent version of each node, 
-  # even if it's moved.  For revert (version=1+), uses the node in existence 
+  # For undelete (version<0), always uses the most recent version of each node, 
+  # even if it's moved.  For revert (version >= 0), uses the node in existence 

   # at the time, generating a new id if it's still visible and has been moved/
   # retagged.
   # at the time, generating a new id if it's still visible and has been moved/
   # retagged.

-
-  def getway_old(id, version) #:doc:
-       if version < 0
-         old_way = OldWay.find(:first, :conditions => ['visible = 1 AND id = ?', id], :order => 'version DESC')
-         points = old_way.get_nodes_undelete
-       else
-         old_way = OldWay.find(:first, :conditions => ['id = ? AND version = ?', id, version])
-         points = old_way.get_nodes_revert
-       end
-
-       old_way.tags['history'] = "Retrieved from v#{old_way.version}"
-
-       [0, id, points, old_way.tags, old_way.version]
+  #
+  # Returns:
+  # 0. success code, 
+  # 1. id, 
+  # 2. array of points, 
+  # 3. hash of tags, 
+  # 4. version, 
+  # 5. is this the current, visible version? (boolean)
+  
+  def getway_old(id, timestamp) #:doc:
+    if timestamp == ''
+      # undelete
+      old_way = OldWay.find(:first, :conditions => ['visible = ? AND id = ?', true, id], :order => 'version DESC')
+      points = old_way.get_nodes_undelete unless old_way.nil?
+    else
+      begin
+        # revert
+        timestamp = DateTime.strptime(timestamp.to_s, "%d %b %Y, %H:%M:%S")
+        old_way = OldWay.find(:first, :conditions => ['id = ? AND timestamp <= ?', id, timestamp], :order => 'timestamp DESC')
+        unless old_way.nil?
+          points = old_way.get_nodes_revert(timestamp)
+          if !old_way.visible
+            return [-1, "Sorry, the way was deleted at that time - please revert to a previous version."]
+          end
+        end
+      rescue ArgumentError
+        # thrown by date parsing method. leave old_way as nil for
+        # the superb error handler below.
+      end
+    end
+
+    if old_way.nil?
+      # *** FIXME: shouldn't this be returning an error?
+      return [-1, id, [], {}, -1,0]
+    else
+      curway=Way.find(id)
+      old_way.tags['history'] = "Retrieved from v#{old_way.version}"
+      return [0, id, points, old_way.tags, curway.version, (curway.version==old_way.version and curway.visible)]
+    end

   end
   
   end
   

-  # Find history of a way. Returns 'way', id, and 
-  # an array of previous versions.
+  # Find history of a way.
+  # Returns 'way', id, and an array of previous versions:
+  # - formerly [old_way.version, old_way.timestamp.strftime("%d %b %Y, %H:%M"), old_way.visible ? 1 : 0, user, uid]
+  # - now [timestamp,user,uid]
+  #
+  # Heuristic: Find all nodes that have ever been part of the way; 
+  # get a list of their revision dates; add revision dates of the way;
+  # sort and collapse list (to within 2 seconds); trim all dates before the 
+  # start date of the way.

 
   def getway_history(wayid) #:doc:
 
   def getway_history(wayid) #:doc:

-       history = Way.find(wayid).old_ways.reverse.collect do |old_way|
-         user = old_way.user.data_public? ? old_way.user.display_name : 'anonymous'
-         uid  = old_way.user.data_public? ? old_way.user.id : 0
-         [old_way.version, old_way.timestamp.strftime("%d %b %Y, %H:%M"), old_way.visible ? 1 : 0, user, uid]
-       end

 
 

-       ['way',wayid,history]
+    begin
+      # Find list of revision dates for way and all constituent nodes
+      revdates=[]
+      revusers={}
+      Way.find(wayid).old_ways.collect do |a|
+        revdates.push(a.timestamp)
+        unless revusers.has_key?(a.timestamp.to_i) then revusers[a.timestamp.to_i]=change_user(a) end
+        a.nds.each do |n|
+          Node.find(n).old_nodes.collect do |o|
+            revdates.push(o.timestamp)
+            unless revusers.has_key?(o.timestamp.to_i) then revusers[o.timestamp.to_i]=change_user(o) end
+          end
+        end
+      end
+      waycreated=revdates[0]
+      revdates.uniq!
+      revdates.sort!
+         revdates.reverse!
+
+      # Remove any dates (from nodes) before first revision date of way
+      revdates.delete_if { |d| d<waycreated }
+      # Remove any elements where 2 seconds doesn't elapse before next one
+      revdates.delete_if { |d| revdates.include?(d+1) or revdates.include?(d+2) }
+      # Collect all in one nested array
+      revdates.collect! {|d| [d.strftime("%d %b %Y, %H:%M:%S")] + revusers[d.to_i] }
+
+      return ['way',wayid,revdates]
+    rescue ActiveRecord::RecordNotFound
+      return ['way', wayid, []]
+    end

   end
   end

-
-  # Find history of a node. Returns 'node', id, and 
-  # an array of previous versions.
+  
+  # Find history of a node. Returns 'node', id, and an array of previous versions as above.

 
   def getnode_history(nodeid) #:doc:
 
   def getnode_history(nodeid) #:doc:

-       history = Node.find(nodeid).old_nodes.reverse.collect do |old_node|
-         user = old_node.user.data_public? ? old_node.user.display_name : 'anonymous'
-         uid  = old_node.user.data_public? ? old_node.user.id : 0
-         [old_node.timestamp.to_i, old_node.timestamp.strftime("%d %b %Y, %H:%M"), old_node.visible ? 1 : 0, user, uid]
-       end
+    begin 
+      history = Node.find(nodeid).old_nodes.reverse.collect do |old_node|
+        [old_node.timestamp.strftime("%d %b %Y, %H:%M:%S")] + change_user(old_node)
+      end
+      return ['node', nodeid, history]
+    rescue ActiveRecord::RecordNotFound
+      return ['node', nodeid, []]
+    end
+  end

 
 

-       ['node',nodeid,history]
+  def change_user(obj)
+    user_object = obj.changeset.user
+    user = user_object.data_public? ? user_object.display_name : 'anonymous'
+    uid  = user_object.data_public? ? user_object.id : 0
+    [user,uid]
+  end
+
+  # Find GPS traces with specified name/id.
+  # Returns array listing GPXs, each one comprising id, name and description.
+  
+  def findgpx(searchterm, usertoken)
+    user = getuser(usertoken)
+    if !uid then return -1,"You must be logged in to search for GPX traces." end
+
+    gpxs = []
+    if searchterm.to_i>0 then
+      gpx = Trace.find(searchterm.to_i, :conditions => ["visible=? AND (public=? OR user_id=?)",true,true,user.id] )
+      if gpx then
+        gpxs.push([gpx.id, gpx.name, gpx.description])
+      end
+    else
+      Trace.find(:all, :limit => 21, :conditions => ["visible=? AND (public=? OR user_id=?) AND MATCH(name) AGAINST (?)",true,true,user.id,searchterm] ).each do |gpx|
+      gpxs.push([gpx.id, gpx.name, gpx.description])
+         end
+       end
+    gpxs

   end
 
   # Get a relation with all tags and members.
   # Returns:
   # 0. relation id,
   # 1. hash of tags,
   end
 
   # Get a relation with all tags and members.
   # Returns:
   # 0. relation id,
   # 1. hash of tags,

-  # 2. list of members.
+  # 2. list of members,
+  # 3. version.

   
   def getrelation(relid) #:doc:
   
   def getrelation(relid) #:doc:

-       rel = Relation.find(relid)
-
-       [relid, rel.tags, rel.members]
+    begin
+      rel = Relation.find(relid)
+    rescue ActiveRecord::RecordNotFound
+      return [relid, {}, []]
+    end
+
+    return [relid, {}, [], nil] if rel.nil? or !rel.visible
+    [relid, rel.tags, rel.members, rel.version]

   end
 
   # Find relations with specified name/id.
   # Returns array of relations, each in same form as getrelation.
   
   def findrelations(searchterm)
   end
 
   # Find relations with specified name/id.
   # Returns array of relations, each in same form as getrelation.
   
   def findrelations(searchterm)

-       rels = []
-       if searchterm.to_i>0 then
-         rel = Relation.find(searchterm.to_i)
-         if rel and rel.visible then
-           rels.push([rel.id, rel.tags, rel.members])
-         end
-       else
-         RelationTag.find(:all, :limit => 11, :conditions => ["match(v) against (?)", searchterm] ).each do |t|
-               if t.relation.visible then
+    rels = []
+    if searchterm.to_i>0 then
+      rel = Relation.find(searchterm.to_i)
+      if rel and rel.visible then
+        rels.push([rel.id, rel.tags, rel.members])
+      end
+    else
+      RelationTag.find(:all, :limit => 11, :conditions => ["match(v) against (?)", searchterm] ).each do |t|
+      if t.relation.visible then

              rels.push([t.relation.id, t.relation.tags, t.relation.members])
            end
          end
        end
              rels.push([t.relation.id, t.relation.tags, t.relation.members])
            end
          end
        end

-       rels
+    rels

   end
 
   # Save a relation.
   end
 
   # Save a relation.


@@ -273,226 +453,335 @@ class AmfController < ApplicationController
   # 1. original relation id (unchanged),
   # 2. new relation id.
 
   # 1. original relation id (unchanged),
   # 2. new relation id.
 

-  def putrelation(renumberednodes, renumberedways, usertoken, relid, tags, members, visible) #:doc:
-       uid = getuserid(usertoken)
-       if !uid then return -1,"You are not logged in, so the relation could not be saved." end
-
-       relid = relid.to_i
-       visible = visible.to_i
-
-       # create a new relation, or find the existing one
-       if relid <= 0
-         rel = Relation.new
-       else
-         rel = Relation.find(relid)
-       end
-
-       # check the members are all positive, and correctly type
-       typedmembers = []
-       members.each do |m|
-         mid = m[1].to_i
-         if mid < 0
-               mid = renumberednodes[mid] if m[0] == 'node'
-               mid = renumberedways[mid] if m[0] == 'way'
-         end
-      if mid
-           typedmembers << [m[0], mid, m[2]]
-         end
-       end
-
-       # assign new contents
-       rel.members = typedmembers
-       rel.tags = tags
-       rel.visible = visible
-       rel.user_id = uid
-
-       # check it then save it
-       # BUG: the following is commented out because it always fails on my
-       #  install. I think it's a Rails bug.
-
-       #if !rel.preconditions_ok?
-       #  return -2, "Relation preconditions failed"
-       #else
-         rel.save_with_history!
-       #end
-
-       [0, relid, rel.id]
+  def putrelation(renumberednodes, renumberedways, usertoken, changeset_id, version, relid, tags, members, visible) #:doc:
+    user = getuser(usertoken)
+    if !user then return -1,"You are not logged in, so the relation could not be saved." end
+
+    relid = relid.to_i
+    visible = (visible.to_i != 0)
+
+    new_relation = nil
+    relation = nil
+    Relation.transaction do
+      # create a new relation, or find the existing one
+      if relid > 0
+        relation = Relation.find(relid)
+      end
+      # We always need a new node, based on the data that has been sent to us
+      new_relation = Relation.new
+
+      # check the members are all positive, and correctly type
+      typedmembers = []
+      members.each do |m|
+        mid = m[1].to_i
+        if mid < 0
+          mid = renumberednodes[mid] if m[0] == 'node'
+          mid = renumberedways[mid] if m[0] == 'way'
+        end
+        if mid
+          typedmembers << [m[0], mid, m[2]]
+        end
+      end
+
+      # assign new contents
+      new_relation.members = typedmembers
+      new_relation.tags = tags
+      new_relation.visible = visible
+      new_relation.changeset_id = changeset_id
+      new_relation.version = version
+
+      # NOTE: id or relid here? id doesn't seem to be set above
+      if relid <= 0
+        # We're creating the node
+        new_relation.create_with_history(user)
+      elsif visible
+        # We're updating the node
+        relation.update_from(new_relation, user)
+      else
+        # We're deleting the node
+        relation.delete_with_history!(new_relation, user)
+      end
+    end # transaction
+      
+    if id <= 0
+      return [0, relid, new_relation.id, new_relation.version]
+    else
+      return [0, relid, relation.id, relation.version]
+    end
+  rescue OSM::APIChangesetAlreadyClosedError => ex
+    return [-1, "The changeset #{ex.changeset.id} was closed at #{ex.changeset.closed_at}."]
+  rescue OSM::APIVersionMismatchError => ex
+    # Really need to check to see whether this is a server load issue, and the 
+    # last version was in the same changeset, or belongs to the same user, then
+    # we can return something different
+    return [-3, "Sorry, someone else has changed this relation since you started editing. Please click the 'Edit' tab to reload the area."]
+  rescue OSM::APIAlreadyDeletedError => ex
+    return [-1, "The relation has already been deleted."]
+  rescue OSM::APIError => ex
+    # Some error that we don't specifically catch
+    return [-2, "Something really bad happened :-( ."]

   end
 
   # Save a way to the database, including all nodes. Any nodes in the previous
   # version and no longer used are deleted.
   # 
   end
 
   # Save a way to the database, including all nodes. Any nodes in the previous
   # version and no longer used are deleted.
   # 

+  # Parameters:
+  # 0. hash of renumbered nodes (added by amf_controller)
+  # 1. current user token (for authentication)
+  # 2. current changeset
+  # 3. new way version
+  # 4. way ID
+  # 5. list of nodes in way
+  # 6. hash of way tags
+  # 7. array of nodes to change (each one is [lon,lat,id,version,tags])
+  # 

   # Returns:
   # 0. '0' (code for success),
   # 1. original way id (unchanged),
   # 2. new way id,
   # Returns:
   # 0. '0' (code for success),
   # 1. original way id (unchanged),
   # 2. new way id,

-  # 3. hash of renumbered nodes (old id=>new id)
+  # 3. hash of renumbered nodes (old id=>new id),
+  # 4. way version,
+  # 5. hash of node versions (node=>version)

 
 

-  def putway(renumberednodes, usertoken, originalway, points, attributes) #:doc:
+  def putway(renumberednodes, usertoken, changeset_id, wayversion, originalway, pointlist, attributes, nodes) #:doc:

 
 

-       # -- Initialise and carry out checks
+    # -- Initialise

        
        

-       uid = getuserid(usertoken)
-       if !uid then return -1,"You are not logged in, so the way could not be saved." end
-
-       originalway = originalway.to_i
-
-       points.each do |a|
-         if a[2] == 0 or a[2].nil? then return -2,"Server error - node with id 0 found in way #{originalway}." end
-         if a[1] == 90 then return -2,"Server error - node with lat -90 found in way #{originalway}." end
-       end
-
-       if points.length < 2 then return -2,"Server error - way is only #{points.length} points long." end
-
-       # -- Get unique nodes
-
-       if originalway < 0
-         way = Way.new
-         uniques = []
-       else
-         way = Way.find(originalway)
-         uniques = way.unshared_node_ids
-       end
-
-       # -- Compare nodes and save changes to any that have changed
-
-       nodes = []
-
-       points.each do |n|
-         lon = n[0].to_f
-         lat = n[1].to_f
-         id = n[2].to_i
-         savenode = false
-
-         if renumberednodes[id]
-           id = renumberednodes[id]
-         elsif id < 0
-               # Create new node
-               node = Node.new
-               savenode = true
-         else
-               node = Node.find(id)
-               nodetags=node.tags_as_hash
-               nodetags.delete('created_by')
-               if !fpcomp(lat, node.lat) or !fpcomp(lon, node.lon) or
-                  n[4] != nodetags or !node.visible?
-                 savenode = true
-               end
-         end
-
-         if savenode
-               node.user_id = uid
-           node.lat = lat
+    user = getuser(usertoken)
+    if !user then return -1,"You are not logged in, so the way could not be saved." end
+    if pointlist.length < 2 then return -2,"Server error - way is only #{points.length} points long." end
+
+    originalway = originalway.to_i
+       pointlist.collect! {|a| a.to_i }
+
+    way=nil    # this is returned, so scope it outside the transaction
+    nodeversions = {}
+    Way.transaction do
+
+      # -- Get unique nodes
+
+      if originalway <= 0
+        uniques = []
+      else
+        way = Way.find(originalway)
+        uniques = way.unshared_node_ids
+      end
+
+      #-- Update each changed node
+
+      nodes.each do |a|
+        lon = a[0].to_f
+        lat = a[1].to_f
+        id = a[2].to_i
+        version = a[3].to_i
+        if id == 0  then return -2,"Server error - node with id 0 found in way #{originalway}." end
+        if lat== 90 then return -2,"Server error - node with latitude -90 found in way #{originalway}." end
+        if renumberednodes[id] then id = renumberednodes[id] end
+
+        node = Node.new
+        node.changeset_id = changeset_id
+        node.lat = lat

         node.lon = lon
         node.lon = lon

-           node.tags = Tags.join(n[4])
-           node.visible = true
-           node.save_with_history!
-
-               if id != node.id
-                 renumberednodes[id] = node.id
-                 id = node.id
-           end
-         end
-
-         uniques = uniques - [id]
-         nodes.push(id)
-       end
-
-       # -- Save revised way
-
-       way.tags = attributes
-       way.nds = nodes
-       way.user_id = uid
-       way.visible = true
-       way.save_with_history!
-
-       # -- Delete any unique nodes
-       
-       uniques.each do |n|
-         deleteitemrelations(n, 'node')
-
-         node = Node.find(n)
-         node.user_id = uid
-         node.visible = false
-         node.save_with_history!
-       end
-
-       [0, originalway, way.id, renumberednodes]
+        node.tags = a[4]
+        node.tags.delete('created_by')
+        node.version = version
+        if id <= 0
+          # We're creating the node
+          node.create_with_history(user)
+          renumberednodes[id] = node.id
+          nodeversions[node.id] = node.version
+        else
+          # We're updating an existing node
+          previous=Node.find(id)
+          previous.update_from(node, user)
+          nodeversions[previous.id] = previous.version
+        end
+      end
+
+      # -- Save revised way
+
+         pointlist.collect! {|a|
+               renumberednodes[a] ? renumberednodes[a]:a
+         } # renumber nodes
+      new_way = Way.new
+      new_way.tags = attributes
+      new_way.nds = pointlist
+      new_way.changeset_id = changeset_id
+      new_way.version = wayversion
+      if originalway <= 0
+        new_way.create_with_history(user)
+        way=new_way    # so we can get way.id and way.version
+      elsif way.tags!=attributes or way.nds!=pointlist or !way.visible?
+        way.update_from(new_way, user)
+      end
+
+      # -- Delete any unique nodes no longer used
+
+      uniques=uniques-pointlist
+      uniques.each do |n|
+        node = Node.find(n)
+        deleteitemrelations(user, changeset_id, id, 'node', node.version)
+        new_node = Node.new
+        new_node.changeset_id = changeset_id
+        new_node.version = node.version
+        node.delete_with_history!(new_node, user)
+      end
+
+    end # transaction
+
+    [0, originalway, way.id, renumberednodes, way.version, nodeversions]
+  rescue OSM::APIChangesetAlreadyClosedError => ex
+    return [-2, "Sorry, your changeset #{ex.changeset.id} has been closed (at #{ex.changeset.closed_at})."]
+  rescue OSM::APIVersionMismatchError => ex
+    # Really need to check to see whether this is a server load issue, and the 
+    # last version was in the same changeset, or belongs to the same user, then
+    # we can return something different
+    return [-3, "Sorry, someone else has changed this way since you started editing. Please click the 'Edit' tab to reload the area."]
+  rescue OSM::APITooManyWayNodesError => ex
+    return [-1, "You have tried to upload a really long way with #{ex.provided} points: only #{ex.max} are allowed."]
+  rescue OSM::APIAlreadyDeletedError => ex
+    return [-1, "The point has already been deleted."]
+  rescue OSM::APIError => ex
+    # Some error that we don't specifically catch
+    return [-2, "Something really bad happened :-(."]

   end
 
   # Save POI to the database.
   # Refuses save if the node has since become part of a way.
   end
 
   # Save POI to the database.
   # Refuses save if the node has since become part of a way.

-  # Returns:
+  # Returns array with:

   # 0. 0 (success),
   # 1. original node id (unchanged),
   # 0. 0 (success),
   # 1. original node id (unchanged),

-  # 2. new node id.
-
-  def putpoi(usertoken, id, lon, lat, tags, visible) #:doc:
-       uid = getuserid(usertoken)
-       if !uid then return -1,"You are not logged in, so the point could not be saved." end
-
-       id = id.to_i
-       visible = (visible.to_i == 1)
-
-       if id > 0 then
-         node = Node.find(id)
-
-         if !visible then
-           unless node.ways.empty? then return -1,"The point has since become part of a way, so you cannot save it as a POI." end
-           deleteitemrelations(id, 'node')
-         end
-       else
-         node = Node.new
-       end
-
-       node.user_id = uid
-       node.lat = lat
-       node.lon = lon
-       node.tags = Tags.join(tags)
-       node.visible = visible
-       node.save_with_history!
-
-       [0, id, node.id]
+  # 2. new node id,
+  # 3. version.
+
+  def putpoi(usertoken, changeset_id, version, id, lon, lat, tags, visible) #:doc:
+    user = getuser(usertoken)
+    if !user then return -1,"You are not logged in, so the point could not be saved." end
+
+    id = id.to_i
+    visible = (visible.to_i == 1)
+    node = nil
+    new_node = nil
+    Node.transaction do
+      if id > 0 then
+        node = Node.find(id)
+
+        if !visible then
+          unless node.ways.empty? then return -1,"The point has since become part of a way, so you cannot save it as a POI." end
+        end
+      end
+      # We always need a new node, based on the data that has been sent to us
+      new_node = Node.new
+
+      new_node.changeset_id = changeset_id
+      new_node.version = version
+      new_node.lat = lat
+      new_node.lon = lon
+      new_node.tags = tags
+      if id <= 0 
+        # We're creating the node
+        new_node.create_with_history(user)
+      elsif visible
+        # We're updating the node
+        node.update_from(new_node, user)
+      else
+        # We're deleting the node
+        node.delete_with_history!(new_node, user)
+      end
+     end # transaction
+
+    if id <= 0
+      return [0, id, new_node.id, new_node.version]
+    else
+      return [0, id, node.id, node.version]
+    end 
+  rescue OSM::APIChangesetAlreadyClosedError => ex
+    return [-1, "The changeset #{ex.changeset.id} was closed at #{ex.changeset.closed_at}"]
+  rescue OSM::APIVersionMismatchError => ex
+    # Really need to check to see whether this is a server load issue, and the 
+    # last version was in the same changeset, or belongs to the same user, then
+    # we can return something different
+    return [-3, "Sorry, someone else has changed this point since you started editing. Please click the 'Edit' tab to reload the area."]
+  rescue OSM::APIAlreadyDeletedError => ex
+    return [-1, "The point has already been deleted"]
+  rescue OSM::APIError => ex
+    # Some error that we don't specifically catch
+    return [-2, "Something really bad happened :-()"]

   end
 
   # Read POI from database
   # (only called on revert: POIs are usually read by whichways).
   #
   end
 
   # Read POI from database
   # (only called on revert: POIs are usually read by whichways).
   #

-  # Returns array of id, long, lat, hash of tags.
+  # Returns array of id, long, lat, hash of tags, version.

 
   def getpoi(id,timestamp) #:doc:
 
   def getpoi(id,timestamp) #:doc:

-       if timestamp>0 then
-         n = OldNode.find(id, :conditions=>['UNIX_TIMESTAMP(timestamp)=?',timestamp])
-       else
-         n = Node.find(id)
-       end
-
-       if n
-         return [n.id, n.lon, n.lat, n.tags_as_hash]
-       else
-         return [nil, nil, nil, '']
-       end
+    if timestamp == '' then
+      n = Node.find(id)
+    else
+      n = OldNode.find(id, :conditions=>['timestamp=?',DateTime.strptime(timestamp, "%d %b %Y, %H:%M:%S")])
+    end
+
+    if n
+      return [n.id, n.lon, n.lat, n.tags, n.version]
+    else
+      return [nil, nil, nil, {}, nil]
+    end

   end
 
   # Delete way and all constituent nodes. Also removes from any relations.
   end
 
   # Delete way and all constituent nodes. Also removes from any relations.

+  # Params:
+  # * The user token
+  # * the changeset id
+  # * the id of the way to change
+  # * the version of the way that was downloaded
+  # * a hash of the id and versions of all the nodes that are in the way, if any 
+  # of the nodes have been changed by someone else then, there is a problem!

   # Returns 0 (success), unchanged way id.
 
   # Returns 0 (success), unchanged way id.
 

-  def deleteway(usertoken, way_id) #:doc:
-       uid = getuserid(usertoken)
-       if !uid then return -1,"You are not logged in, so the way could not be deleted." end
-
-       # FIXME: would be good not to make two history entries when removing
-       #                two nodes from the same relation
-       user = User.find(uid)
-       way = Way.find(way_id)
-       way.unshared_node_ids.each do |n|
-         deleteitemrelations(n, 'node')
-       end
-       deleteitemrelations(way_id, 'way')
-
-       way.delete_with_relations_and_nodes_and_history(user)  
-
-       [0, way_id]
+  def deleteway(usertoken, changeset_id, way_id, way_version, node_id_version) #:doc:
+    user = getuser(usertoken)
+    unless user then return -1,"You are not logged in, so the way could not be deleted." end
+      
+    way_id = way_id.to_i
+    # Need a transaction so that if one item fails to delete, the whole delete fails.
+    Way.transaction do
+
+      # delete the way
+      old_way = Way.find(way_id)
+      delete_way = Way.new
+      delete_way.version = way_version
+      delete_way.changeset_id = changeset_id
+      old_way.delete_with_history!(delete_way, user)
+
+      old_way.unshared_node_ids.each do |node_id|
+        # delete the node
+        node = Node.find(node_id)
+        delete_node = Node.new
+        delete_node.changeset_id = changeset_id
+        if node_id_version[node_id.to_s]
+          delete_node.version = node_id_version[node_id.to_s]
+        else
+          # in case the node wasn't passed (i.e. if it was previously removed
+          # from the way in Potlatch)
+          deleteitemrelations(user, changeset_id, node_id, 'node', node.version)
+             delete_node.version = node.version
+           end
+        node.delete_with_history!(delete_node, user)
+      end
+    end # transaction
+    [0, way_id]
+  rescue OSM::APIChangesetAlreadyClosedError => ex
+    return [-1, "The changeset #{ex.changeset.id} was closed at #{ex.changeset.closed_at}"]
+  rescue OSM::APIVersionMismatchError => ex
+    # Really need to check to see whether this is a server load issue, and the 
+    # last version was in the same changeset, or belongs to the same user, then
+    # we can return something different
+    return [-3, "Sorry, someone else has changed this way since you started editing. Please click the 'Edit' tab to reload the area."]
+  rescue OSM::APIAlreadyDeletedError => ex
+    return [-1, "The way has already been deleted."]
+  rescue OSM::APIError => ex
+    # Some error that we don't specifically catch
+    return [-2, "Something really bad happened :-( ."]

   end
 
 
   end
 
 


@@ -500,141 +789,147 @@ class AmfController < ApplicationController
   # Support functions
 
   # Remove a node or way from all relations
   # Support functions
 
   # Remove a node or way from all relations

+  # This is only used by putway and deleteway when deleting nodes removed 
+  # from a way (because Potlatch itself doesn't keep track of these - 
+  # possible FIXME).

 
 

-  def deleteitemrelations(objid, type) #:doc:
-       relations = RelationMember.find(:all, 
+  def deleteitemrelations(user, changeset_id, objid, type, version) #:doc:
+    relations = RelationMember.find(:all, 

                                                                        :conditions => ['member_type = ? and member_id = ?', type, objid], 
                                                                        :include => :relation).collect { |rm| rm.relation }.uniq
 
                                                                        :conditions => ['member_type = ? and member_id = ?', type, objid], 
                                                                        :include => :relation).collect { |rm| rm.relation }.uniq
 

-       relations.each do |rel|
-         rel.members.delete_if { |x| x[0] == type and x[1] == objid }
-         rel.save_with_history!
-       end
-  end
-
-  # Break out node tags into a hash
-  # (should become obsolete as of API 0.6)
-
-  def tagstring_to_hash(a) #:doc:
-       tags={}
-       Tags.split(a) do |k, v|
-         tags[k]=v
-       end
-       tags
+    relations.each do |rel|
+      rel.members.delete_if { |x| x[0] == type and x[1] == objid }
+      new_rel = Relation.new
+      new_rel.tags = rel.tags
+      new_rel.visible = rel.visible
+      new_rel.version = rel.version
+      new_rel.members = rel.members
+      new_rel.changeset_id = changeset_id
+      rel.update_from(new_rel, user)
+    end

   end
 
   # Authenticate token
   # (can also be of form user:pass)
   end
 
   # Authenticate token
   # (can also be of form user:pass)

-
-  def getuserid(token) #:doc:
-       if (token =~ /^(.+)\:(.+)$/) then
-         user = User.authenticate(:username => $1, :password => $2)
-       else
-         user = User.authenticate(:token => token)
-       end
-
-       return user ? user.id : nil;
-  end
-
-  # Compare two floating-point numbers to within 0.0000001
-
-  def fpcomp(a,b) #:doc:
-       return ((a/0.0000001).round==(b/0.0000001).round)
+  # When we are writing to the api, we need the actual user model, 
+  # not just the id, hence this abstraction
+
+  def getuser(token) #:doc:
+    if (token =~ /^(.+)\:(.+)$/) then
+      user = User.authenticate(:username => $1, :password => $2)
+    else
+      user = User.authenticate(:token => token)
+    end
+    return user

   end
 
   # Send AMF response
   
   def sendresponse(results)
   end
 
   # Send AMF response
   
   def sendresponse(results)

-       a,b=results.length.divmod(256)
-       render :content_type => "application/x-amf", :text => proc { |response, output| 
-         output.write 0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
-         results.each do |k,v|
-               output.write(v)
-         end
-       }
+    a,b=results.length.divmod(256)
+    render :content_type => "application/x-amf", :text => proc { |response, output| 
+      # ** move amf writing loop into here - 
+      # basically we read the messages in first (into an array of some sort),
+      # then iterate through that array within here, and do all the AMF writing
+      output.write 0.chr+0.chr+0.chr+0.chr+a.chr+b.chr
+      results.each do |k,v|
+        output.write(v)
+      end
+    }

   end
 
 
   # ====================================================================
   # Alternative SQL queries for getway/whichways
 
   end
 
 
   # ====================================================================
   # Alternative SQL queries for getway/whichways
 

-  def sql_find_way_ids_in_area(xmin,ymin,xmax,ymax)
-       sql=<<-EOF
-  SELECT DISTINCT current_way_nodes.id AS wayid
-               FROM current_way_nodes
-  INNER JOIN current_nodes ON current_nodes.id=current_way_nodes.node_id
-  INNER JOIN current_ways  ON current_ways.id =current_way_nodes.id
-          WHERE current_nodes.visible=1 
-                AND current_ways.visible=1 
-                AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
-       EOF
-       return ActiveRecord::Base.connection.select_all(sql).collect { |a| a['wayid'].to_i }
+  def sql_find_ways_in_area(xmin,ymin,xmax,ymax)
+    sql=<<-EOF
+    SELECT DISTINCT current_ways.id AS wayid,current_ways.version AS version
+      FROM current_way_nodes
+    INNER JOIN current_nodes ON current_nodes.id=current_way_nodes.node_id
+    INNER JOIN current_ways  ON current_ways.id =current_way_nodes.id
+       WHERE current_nodes.visible=TRUE 
+       AND current_ways.visible=TRUE 
+       AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
+    EOF
+    return ActiveRecord::Base.connection.select_all(sql).collect { |a| [a['wayid'].to_i,a['version'].to_i] }

   end
        
   def sql_find_pois_in_area(xmin,ymin,xmax,ymax)
   end
        
   def sql_find_pois_in_area(xmin,ymin,xmax,ymax)

-       sql=<<-EOF
-                 SELECT current_nodes.id,current_nodes.latitude*0.0000001 AS lat,current_nodes.longitude*0.0000001 AS lon,current_nodes.tags 
+    pois=[]
+    sql=<<-EOF
+                 SELECT current_nodes.id,current_nodes.latitude*0.0000001 AS lat,current_nodes.longitude*0.0000001 AS lon,current_nodes.version 

                        FROM current_nodes 
                        FROM current_nodes 

- LEFT OUTER JOIN current_way_nodes cwn ON cwn.node_id=current_nodes.id 
-                  WHERE current_nodes.visible=1
+       LEFT OUTER JOIN current_way_nodes cwn ON cwn.node_id=current_nodes.id 
+                  WHERE current_nodes.visible=TRUE

                         AND cwn.id IS NULL
                         AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}
                         AND cwn.id IS NULL
                         AND #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "current_nodes.")}

-       EOF
-       return ActiveRecord::Base.connection.select_all(sql).collect { |n| [n['id'].to_i,n['lon'].to_f,n['lat'].to_f,tagstring_to_hash(n['tags'])] }
+    EOF
+    ActiveRecord::Base.connection.select_all(sql).each do |row|
+      poitags={}
+      ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_node_tags WHERE id=#{row['id']}").each do |n|
+        poitags[n['k']]=n['v']
+      end
+      pois << [row['id'].to_i, row['lon'].to_f, row['lat'].to_f, poitags, row['version'].to_i]
+    end
+    pois

   end
        
   def sql_find_relations_in_area_and_ways(xmin,ymin,xmax,ymax,way_ids)
   end
        
   def sql_find_relations_in_area_and_ways(xmin,ymin,xmax,ymax,way_ids)

-       # ** It would be more Potlatchy to get relations for nodes within ways
-       #    during 'getway', not here
-       sql=<<-EOF
-         SELECT DISTINCT cr.id AS relid 
-               FROM current_relations cr
-  INNER JOIN current_relation_members crm ON crm.id=cr.id 
-  INNER JOIN current_nodes cn ON crm.member_id=cn.id AND crm.member_type='node' 
-          WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "cn.")}
-       EOF
-       unless way_ids.empty?
-         sql+=<<-EOF
-          UNION
-         SELECT DISTINCT cr.id AS relid
-               FROM current_relations cr
-  INNER JOIN current_relation_members crm ON crm.id=cr.id
-          WHERE crm.member_type='way' 
-                AND crm.member_id IN (#{way_ids.join(',')})
-         EOF
-       end
-       return ActiveRecord::Base.connection.select_all(sql).collect { |a| a['relid'].to_i }.uniq
+    # ** It would be more Potlatchy to get relations for nodes within ways
+    #    during 'getway', not here
+    sql=<<-EOF
+      SELECT DISTINCT cr.id AS relid,cr.version AS version 
+      FROM current_relations cr
+      INNER JOIN current_relation_members crm ON crm.id=cr.id 
+      INNER JOIN current_nodes cn ON crm.member_id=cn.id AND crm.member_type='node' 
+       WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "cn.")}
+      EOF
+    unless way_ids.empty?
+      sql+=<<-EOF
+       UNION
+        SELECT DISTINCT cr.id AS relid,cr.version AS version
+        FROM current_relations cr
+        INNER JOIN current_relation_members crm ON crm.id=cr.id
+         WHERE crm.member_type='way' 
+         AND crm.member_id IN (#{way_ids.join(',')})
+        EOF
+    end
+    return ActiveRecord::Base.connection.select_all(sql).collect { |a| [a['relid'].to_i,a['version'].to_i] }

   end
        
   def sql_get_nodes_in_way(wayid)
   end
        
   def sql_get_nodes_in_way(wayid)

-       points=[]
-       sql=<<-EOF
-               SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,current_nodes.id,tags 
-                 FROM current_way_nodes,current_nodes 
-                WHERE current_way_nodes.id=#{wayid.to_i} 
+    points=[]
+    sql=<<-EOF
+      SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,current_nodes.id 
+      FROM current_way_nodes,current_nodes 
+       WHERE current_way_nodes.id=#{wayid.to_i} 

                   AND current_way_nodes.node_id=current_nodes.id 
                   AND current_way_nodes.node_id=current_nodes.id 

-                  AND current_nodes.visible=1
-         ORDER BY sequence_id
+                  AND current_nodes.visible=TRUE
+      ORDER BY sequence_id

          EOF
          EOF

-       ActiveRecord::Base.connection.select_all(sql).each do |row|
-         nodetags=tagstring_to_hash(row['tags'])
-         nodetags.delete('created_by')
-         points << [row['lon'].to_f,row['lat'].to_f,row['id'].to_i,nodetags]
-       end
-       points
+    ActiveRecord::Base.connection.select_all(sql).each do |row|
+      nodetags={}
+      ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_node_tags WHERE id=#{row['id']}").each do |n|
+        nodetags[n['k']]=n['v']
+      end
+      nodetags.delete('created_by')
+      points << [row['lon'].to_f,row['lat'].to_f,row['id'].to_i,nodetags]
+    end
+    points

   end
        
   def sql_get_tags_in_way(wayid)
   end
        
   def sql_get_tags_in_way(wayid)

-       tags={}
-       ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_way_tags WHERE id=#{wayid.to_i}").each do |row|
-         tags[row['k']]=row['v']
-       end
-       tags
+    tags={}
+    ActiveRecord::Base.connection.select_all("SELECT k,v FROM current_way_tags WHERE id=#{wayid.to_i}").each do |row|
+      tags[row['k']]=row['v']
+    end
+    tags

   end
 
   end
 

+  def sql_get_way_version(wayid)
+    ActiveRecord::Base.connection.select_one("SELECT version FROM current_ways WHERE id=#{wayid.to_i}")
+  end

 end
 
 end
 

-# Local Variables:
-# indent-tabs-mode: t
-# tab-width: 4
-# End: