Nuked 'browse.start_rjs.unable_to_load' and replaced it with

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

diff --git a/app/controllers/amf_controller.rb b/app/controllers/amf_controller.rb
index 39de7e671650a5192235034d012b8e22079f73d6..dd04382187e7c760af923c4fc9d8d3d8430fe665 100644 (file)
--- a/app/controllers/amf_controller.rb
+++ b/app/controllers/amf_controller.rb
@@ -24,10 +24,16 @@
 # == Debugging
 # 
 # Any method that returns a status code (0 for ok) can also send:
 # == Debugging
 # 
 # Any method that returns a status code (0 for ok) can also send:

-#      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
+# return(-3,["type",v],id)    <-- version conflict
+# return(-4,"type",id)        <-- object not found
+# -5 indicates the method wasn't called (due to a previous error)

 # 
 # 

-# 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'
 
 class AmfController < ApplicationController
   require 'stringio'


@@ -37,227 +43,296 @@ class AmfController < ApplicationController
   # Help methods for checking boundary sanity and area size
   include MapBoundary
 
   # Help methods for checking boundary sanity and area size
   include MapBoundary
 

-  session :off
-  before_filter :check_write_availability
+  before_filter :check_api_writable

 
   # Main AMF handlers: process the raw AMF string (using AMF library) and
   # calls each action (private method) accordingly.
   # ** FIXME: refactor to reduce duplication of code across read/write
   
   def amf_read
 
   # Main AMF handlers: process the raw AMF string (using AMF library) and
   # calls each action (private method) accordingly.
   # ** 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
+    if request.post?
+      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
+      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].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 '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))
+      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}(#{args.join(',')}):#{index}")
+
+        case message
+          when 'getpresets';        results[index]=AMF.putdata(index,getpresets(args[0]))
+          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
       end

+      logger.info("Encoding AMF results")
+      sendresponse(results)
+    else
+      render :nothing => true, :status => :method_not_allowed

     end
     end

-    logger.info("encoding AMF results")
-    sendresponse(results)

   end
 
   def amf_write
   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
+    if request.post?
+      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)
-                                                                       renumberednodes=r[3]
-                                                                       if r[1] != r[2] then renumberedways[r[1]] = r[2] end
-                                                                       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))
-        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))
+      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)
+        err=false                   # Abort batch on error
+
+        logger.info("Executing AMF #{message}:#{index}")
+        if err
+          results[index]=[-5,nil]
+        else
+          case message
+            when 'putway';         orn=renumberednodes.dup
+                                   r=putway(renumberednodes,*args)
+                                   renumberednodes=r[4].dup
+                                   r[4].delete_if { |k,v| orn.has_key?(k) }
+                                   if r[2] != r[3] then renumberedways[r[2]] = r[3] end
+                                   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))
+            when 'putpoi';         r=putpoi(*args)
+                                    if r[2] != r[3] then renumberednodes[r[2]] = r[3] end
+                                   results[index]=AMF.putdata(index,r)
+            when 'startchangeset'; results[index]=AMF.putdata(index,startchangeset(*args))
+           end
+          if results[index][0]==-3 then err=true end  # If a conflict is detected, don't execute any more writes
+        end

       end
       end

+      logger.info("Encoding AMF results")
+      sendresponse(results)
+    else
+      render :nothing => true, :status => :method_not_allowed

     end
     end

-    sendresponse(results)

   end
 
   private
 
   end
 
   private
 

+  def amf_handle_error(call)
+    yield
+  rescue OSM::APIVersionMismatchError => ex
+    return [-3, [ex.type.downcase, ex.latest, ex.id]]
+  rescue OSM::APIUserChangesetMismatchError => ex
+    return [-2, ex.to_s]
+  rescue OSM::APIBadBoundingBox => ex
+    return [-2, "Sorry - I can't get the map for that area. The server said: #{ex.to_s}"]
+  rescue OSM::APIError => ex
+    return [-1, ex.to_s]
+  rescue Exception => ex
+    return [-2, "An unusual error happened (in #{call}). The server said: #{ex.to_s}"]
+  end
+
+  def amf_handle_error_with_timeout(call)
+    amf_handle_error(call) do
+      Timeout::timeout(APP_CONFIG['api_timeout'], OSM::APITimeoutError) do
+        yield
+      end
+    end
+  end
+

   # Start new changeset
   # Start new changeset

+  # Returns success_code,success_message,changeset id

   
   

-  def startchangeset(usertoken, cstags, closeid, closecomment)
-    user = getuserid(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 closecomment.empty?
-        cs.save!
-      else
-        cs.tags['comment']=closecomment
+  def startchangeset(usertoken, cstags, closeid, closecomment, opennew)
+    amf_handle_error("'startchangeset'") do
+      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
+          raise OSM::APIUserChangesetMismatchError.new
+        elsif closecomment.empty?
+          cs.save!
+        else
+          cs.tags['comment']=closecomment
+          cs.save_with_tags!
+        end
+      end
+       
+      # open a new changeset
+      if opennew!=0
+        cs = Changeset.new
+        cs.tags = cstags
+        cs.user_id = user.id
+        if !closecomment.empty? then cs.tags['comment']=closecomment end
+        # 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!
         cs.save_with_tags!

+        return [0,'',cs.id]
+      else
+        return [0,'',nil]

       end
     end
       end
     end

-       
-    # open a new changeset
-    cs = Changeset.new
-    cs.tags = cstags
-    cs.user_id = uid
-    # Don't like the next two lines. These need to be abstracted to the model more/better
-    cs.created_at = Time.now
-    cs.closed_at = Time.new + 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.
 
   end
 
   # Return presets (default tags, localisation etc.):
   # uses POTLATCH_PRESETS global, set up in OSM::Potlatch.
 

-  def getpresets() #:doc:
-    return POTLATCH_PRESETS
+  def getpresets(lang) #:doc:
+    lang.gsub!(/[^\w\-]/,'')
+
+    begin
+      localised = YAML::load(File.open("#{RAILS_ROOT}/config/potlatch/localised/#{lang}/localised.yaml"))
+    rescue
+      localised = "" # guess we'll just have to use the hardcoded English text instead
+    end
+
+    begin
+      help = File.read("#{RAILS_ROOT}/config/potlatch/localised/#{lang}/help.html")
+    rescue
+      help = File.read("#{RAILS_ROOT}/config/potlatch/localised/en/help.html")
+    end
+    return POTLATCH_PRESETS+[localised,help]

   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: 
+  # [success_code, success_message,
+  #  [[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:

-    xmin -= 0.01; ymin -= 0.01
-    xmax += 0.01; ymax += 0.01
-    
-    # check boundary is sane and area within defined
-    # see /config/application.yml
-    begin
+    amf_handle_error_with_timeout("'whichways'") do
+      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)
       check_boundaries(xmin, ymin, xmax, ymax)

-    rescue Exception => err
-      return [-2,"Sorry - I can't get the map for that area."]
-    end

 
 

-    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.collect { |node| 
-        node.ways.collect { |w| [w.id,w.version] }.flatten
-      }.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] }
-
-      # 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
+      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]
+      [0, '', ways, points, relations]
+    end

   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
+    amf_handle_error_with_timeout("'whichways_deleted'") do
+      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 boundary is sane and area within defined
+      # see /config/application.yml

       check_boundaries(xmin, ymin, xmax, ymax)
       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
+      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]
+      [0,'',way_ids]
+    end

   end
 
   # Get a way including nodes and tags.
   # Returns the way id, a Potlatch-style array of points, a hash of tags, and the version number.
 
   def getway(wayid) #:doc:
   end
 
   # Get a way including nodes and tags.
   # Returns the way id, a Potlatch-style array of points, a hash of tags, and the version number.
 
   def getway(wayid) #:doc:

-    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)
+    amf_handle_error_with_timeout("'getway' #{wayid}") do
+      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
       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
+        way = Way.find(:first, :conditions => { :id => wayid }, :include => { :nodes => :node_tags })

 
         # check case where way has been deleted or doesn't exist
 
         # check case where way has been deleted or doesn't exist

-        return [wayid,[],{}] if way.nil? or !way.visible
+        return [-4, 'way', wayid, [], {}, nil] if way.nil? or !way.visible

 
         points = way.nodes.collect do |node|
 
         points = way.nodes.collect do |node|

-        nodetags=node.tags
-        nodetags.delete('created_by')
-        [node.lon, node.lat, node.id, nodetags]
+          nodetags=node.tags
+          nodetags.delete('created_by')
+          [node.lon, node.lat, node.id, nodetags, node.version]
+        end
+        tags = way.tags
+        version = way.version

       end
       end

-      tags = way.tags
-      version = way.version
-    end

 
 

-    [wayid, points, tags, version]
+      [0, '', wayid, points, tags, version]
+    end

   end
   end

-
+  

   # Get an old version of a way, and all constituent nodes.
   #
   # For undelete (version<0), always uses the most recent version of each node, 
   # Get an old version of a way, and all constituent nodes.
   #
   # For undelete (version<0), always uses the most recent version of each node, 


@@ -272,98 +347,142 @@ class AmfController < ApplicationController
   # 3. hash of tags, 
   # 4. version, 
   # 5. is this the current, visible version? (boolean)
   # 3. hash of tags, 
   # 4. version, 
   # 5. is this the current, visible version? (boolean)

+  
+  def getway_old(id, timestamp) #:doc:
+    amf_handle_error_with_timeout("'getway_old' #{id}, #{timestamp}") do
+      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.", id, [], {}, nil, false]
+            end
+          end
+        rescue ArgumentError
+          # thrown by date parsing method. leave old_way as nil for
+          # the error handler below.
+        end
+      end

 
 

-  def getway_old(id, version) #:doc:
-    if version < 0
-      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
-      old_way = OldWay.find(:first, :conditions => ['id = ? AND version = ?', id, version])
-      points = old_way.get_nodes_revert unless old_way.nil?
-    end
-
-    if old_way.nil?
-      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, old_way.version, (curway.version==old_way.version and curway.visible)]
+      if old_way.nil?
+        return [-1, "Sorry, the server could not find a way at that time.", id, [], {}, nil, false]
+      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
   
     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:
     begin
 
   def getway_history(wayid) #:doc:
     begin

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

-
-      return ['way',wayid,history]
+      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
     rescue ActiveRecord::RecordNotFound
       return ['way', wayid, []]
     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:

-    begin
-         history = Node.find(nodeid).old_nodes.reverse.collect do |old_node|
-        user_object = old_node.changeset.user
-        user = user_object.data_public? ? user_object.display_name : 'anonymous'
-        uid  = user_object.data_public? ? user_object.id : 0
-        [old_node.version, old_node.timestamp.strftime("%d %b %Y, %H:%M"), old_node.visible ? 1 : 0, user, uid]
+    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
       end

-
-      return ['node',nodeid,history]
+      return ['node', nodeid, history]

     rescue ActiveRecord::RecordNotFound
       return ['node', nodeid, []]
     end
   end
 
     rescue ActiveRecord::RecordNotFound
       return ['node', nodeid, []]
     end
   end
 

+  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)
   # Find GPS traces with specified name/id.
   # Returns array listing GPXs, each one comprising id, name and description.
   
   def findgpx(searchterm, usertoken)

-    uid = getuserid(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,uid] )
-      if gpx then
-        gpxs.push([gpx.id, gpx.name, gpx.description])
+    amf_handle_error_with_timeout("'findgpx'") do
+      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
       end

-    else
-      Trace.find(:all, :limit => 21, :conditions => ["visible=? AND (public=? OR user_id=?) AND MATCH(name) AGAINST (?)",true,true,uid,searchterm] ).each do |gpx|
-      gpxs.push([gpx.id, gpx.name, gpx.description])
-         end
-       end
-    gpxs
+      [0,'',gpxs]
+    end

   end
 
   # Get a relation with all tags and members.
   # Returns:
   end
 
   # Get a relation with all tags and members.
   # Returns:

-  # 0. relation id,
-  # 1. hash of tags,
-  # 2. list of members,
-  # 3. version.
+  # 0. success code?
+  # 1. object type?
+  # 2. relation id,
+  # 3. hash of tags,
+  # 4. list of members,
+  # 5. version.

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

-    begin
-      rel = Relation.find(relid)
-    rescue ActiveRecord::RecordNotFound
-      return [relid, {}, []]
-    end
+    amf_handle_error("'getrelation' #{relid}") do
+      rel = Relation.find(:first, :conditions => { :id => relid })

 
 

-    return [relid, {}, [], nil] if rel.nil? or !rel.visible
-    [relid, rel.tags, rel.members, rel.version]
+      return [-4, 'relation', relid, {}, [], nil] if rel.nil? or !rel.visible
+      [0, '', relid, rel.tags, rel.members, rel.version]
+    end

   end
 
   # Find relations with specified name/id.
   end
 
   # Find relations with specified name/id.


@@ -374,15 +493,15 @@ class AmfController < ApplicationController
     if searchterm.to_i>0 then
       rel = Relation.find(searchterm.to_i)
       if rel and rel.visible then
     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])
+        rels.push([rel.id, rel.tags, rel.members, rel.version])

       end
     else
       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
+      RelationTag.find(:all, :limit => 11, :conditions => ["v like ?", "%#{searchterm}%"] ).each do |t|
+        if t.relation.visible then
+          rels.push([t.relation.id, t.relation.tags, t.relation.members, t.relation.version])
+        end
+      end
+    end

     rels
   end
 
     rels
   end
 


@@ -390,341 +509,315 @@ class AmfController < ApplicationController
   # Returns
   # 0. 0 (success),
   # 1. original relation id (unchanged),
   # Returns
   # 0. 0 (success),
   # 1. original relation id (unchanged),

-  # 2. new relation id.
-
-  def putrelation(renumberednodes, renumberedways, usertoken, changeset, version, relid, tags, members, visible) #:doc:
-    user = getuserid(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)
+  # 2. new relation id,
+  # 3. version.

 
 

-    # 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
+  def putrelation(renumberednodes, renumberedways, usertoken, changeset_id, version, relid, tags, members, visible) #:doc:
+    amf_handle_error("'putrelation' #{relid}")  do
+      user = getuser(usertoken)
+      if !user then return -1,"You are not logged in, so the relation could not be saved." end

 
 

-    # assign new contents
-    new_relation.members = typedmembers
-    new_relation.tags = tags
-    new_relation.visible = visible
-    new_relation.changeset_id = changeset
-    new_relation.version = version
+      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

 
 

-    if id <= 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
+        # 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
+
+        if relid <= 0
+          # We're creating the relation
+          new_relation.create_with_history(user)
+        elsif visible
+          # We're updating the relation
+          new_relation.id = relid
+          relation.update_from(new_relation, user)
+        else
+          # We're deleting the relation
+          new_relation.id = relid
+          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, "You have taken too long to edit, please reload the area"]
-  rescue OSM::APIAlreadyDeletedError => ex
-    return [-1, "The object has already been deleted"]
-  rescue OSM::APIError => ex
-    # Some error that we don't specifically catch
-    return [-2, "Something really bad happened :-()"]
+      if relid <= 0
+        return [0, '', relid, new_relation.id, new_relation.version]
+      else
+        return [0, '', relid, relid, relation.version]
+      end
+   end

   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]),
+  # 8. hash of nodes to delete (id->version).
+  # 

   # Returns:
   # 0. '0' (code for success),
   # 1. original way id (unchanged),
   # 2. new way id,
   # 3. hash of renumbered nodes (old id=>new 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),

-  # 4. version
-
-  def putway(renumberednodes, usertoken, changeset, originalway, points, attributes) #:doc:
+  # 4. way version,
+  # 5. hash of node versions (node=>version)

 
 

-    # -- Initialise and carry out checks
+  def putway(renumberednodes, usertoken, changeset_id, wayversion, originalway, pointlist, attributes, nodes, deletednodes) #:doc:
+    amf_handle_error("'putway' #{originalway}") do
+      # -- Initialise

        
        

-    user = getuser(usertoken)
-    if !user 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
-      uniques = []
-    else
-      way = Way.find(originalway)
-      uniques = way.unshared_node_ids
-    end
-    new_way = Way.new
-
-    # -- 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
-      version = n[3].to_i # FIXME which index does the version come in on????
-      savenode = false
-      # We always need a new node if we are saving it
-      new_node = Node.new
-
-
-      if renumberednodes[id]
-        id = renumberednodes[id]
-      end
-      if id <= 0
-        # Create new node
-        savenode = true
-      else
-        # Don't modify this node, make any changes you want to the new_node above
-        node = Node.find(id)
-        nodetags=node.tags
-        nodetags.delete('created_by')
-        if !fpcomp(lat, node.lat) or !fpcomp(lon, node.lon) or
-           n[4] != nodetags or !node.visible?
-          savenode = true
+      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
+
+        # -- 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.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)
+            node.id=id
+            previous.update_from(node, user)
+            nodeversions[previous.id] = previous.version
+          end

         end
         end

-      end

 
 

-      if savenode
-        new_node.changeset_id = changeset
-        new_node.lat = lat
-        new_node.lon = lon
-        new_node.tags = n[4]
-        new_node.visible = true
-        new_node.version = version
-        if id <= 0
-          # We're creating the node
-          new_node.create_with_history(user)
+        # -- 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

         else
         else

-          # We're updating the node (no delete here)
-          node.update_from(new_node, user)
+          way = Way.find(originalway)
+          if way.tags!=attributes or way.nds!=pointlist or !way.visible?
+            new_way.id=originalway
+          way.update_from(new_way, user)
+          end

         end
 
         end
 

-        if id != node.id
-          renumberednodes[id] = node.id
-          id = node.id
+        # -- Delete unwanted nodes
+
+        deletednodes.each do |id,v|
+          node = Node.find(id.to_i)
+          new_node = Node.new
+          new_node.changeset_id = changeset_id
+          new_node.version = v.to_i
+          new_node.id = id.to_i
+          begin
+            node.delete_with_history!(new_node, user)
+          rescue OSM::APIPreconditionFailedError => ex
+            # We don't do anything here as the node is being used elsewhere
+            # and we don't want to delete it
+          end

         end
         end

-      end

 
 

-      uniques = uniques - [id]
-      nodes.push(id)
-    end
+      end # transaction

 
 

-    # -- Delete any unique nodes
-       
-    uniques.each do |n|
-      deleteitemrelations(n, 'node')
-
-      node = Node.find(n)
-      new_node = Node.new
-      new_node.changeset_id = changeset
-      new_node.version = version
-      node.delete_with_history!(new_node, user)
+      [0, '', originalway, way.id, renumberednodes, way.version, nodeversions, deletednodes]

     end
     end

-
-    # -- Save revised way
-
-    if way.tags!=attributes or way.nds!=nodes or !way.visible?
-      new_way = Way.new
-      new_way.tags = attributes
-      new_way.nds = nodes
-      new_way.changeset_id = changeset
-      new_way.version = version
-      way.update_from(new_way, user)
-    end
-
-    [0, originalway, way.id, renumberednodes, way.version]
-  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, "You have taken too long to edit, please reload the area"]
-  rescue OSM::APIAlreadyDeletedError => ex
-    return [-1, "The object 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.
   # Returns array with:
   # 0. 0 (success),
   end
 
   # Save POI to the database.
   # Refuses save if the node has since become part of a way.
   # Returns array with:
   # 0. 0 (success),

-  # 1. original node id (unchanged),
-  # 2. new node id,
-  # 3. version.
-
-  def putpoi(usertoken, changeset, 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
+  # 1. success message,
+  # 2. original node id (unchanged),
+  # 3. new node id,
+  # 4. version.
+
+  def putpoi(usertoken, changeset_id, version, id, lon, lat, tags, visible) #:doc:
+    amf_handle_error("'putpoi' #{id}") do
+      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.",id,id,version end
+          end
+        end
+        # We always need a new node, based on the data that has been sent to us
+        new_node = Node.new

 
 

-    id = id.to_i
-    visible = (visible.to_i == 1)
+        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
+          new_node.id=id
+          node.update_from(new_node, user)
+        else
+          # We're deleting the node
+          new_node.id=id
+          node.delete_with_history!(new_node, user)
+        end

 
 

-    if id > 0 then
-      node = Node.find(id)
+      end # transaction

 
 

-      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
-    end
-    # We always need a new node, based on the data that has been sent to us
-    new_node = Node.new
-
-    new_node.id = id
-    new_node.changeset_id = changeset
-    new_node.version = version
-    new_node.lat = lat
-    new_node.lon = lon
-    new_node.tags = tags
-    new_node.visible = visible
-    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
-
-    if id <= 0
-      return [0, id, new_node.id, new_node.version]
-    else
-      return [0, id, node.id, node.version]
+      if id <= 0
+        return [0, '', id, new_node.id, new_node.version]
+      else
+        return [0, '', id, node.id, node.version]
+      end 

     end
     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, "You have taken too long to edit, please reload the area"]
-  rescue OSM::APIAlreadyDeletedError => ex
-    return [-1, "The object 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, version.
+  # Returns array of id, long, lat, hash of tags, (current) version.

 
 

-  def getpoi(id,version) #:doc:
-    if version>0 then
-        n = OldNode.find(id, :conditions=>['version=?',version])
-    else
+  def getpoi(id,timestamp) #:doc:
+    amf_handle_error("'getpoi' #{id}") do

       n = Node.find(id)
       n = Node.find(id)

-    end
+      v = n.version
+      unless timestamp == ''
+        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]
+      if n
+        return [0, '', n.id, n.lon, n.lat, n.tags, v]
+      else
+        return [-4, 'node', id, nil, nil, {}, nil]
+      end

     end
   end
 
     end
   end
 

-  # Delete way and all constituent nodes. Also removes from any relations.
-  # Returns 0 (success), unchanged way id.
-
-  def deleteway(usertoken, changeset_id, way_id, version_id) #:doc:
-    user = getuser(usertoken)
-    if user then return -1,"You are not logged in, so the way could not be deleted." end
-    # Need a transaction so that if one item fails to delete, the whole delete fails.
-    Way.transaction do
+  # Delete way and all constituent nodes.
+  # 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, new way version, new node versions.
+
+  def deleteway(usertoken, changeset_id, way_id, way_version, deletednodes) #:doc:
+    amf_handle_error("'deleteway' #{way_id}") do
+      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
       way_id = way_id.to_i

+      nodeversions = {}
+      old_way=nil # returned, so scope it outside the transaction
+      # 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
+        delete_way.id = way_id
+        old_way.delete_with_history!(delete_way, user)
+
+        # -- Delete unwanted nodes
+
+        deletednodes.each do |id,v|
+          node = Node.find(id.to_i)
+          new_node = Node.new
+          new_node.changeset_id = changeset_id
+          new_node.version = v.to_i
+          new_node.id = id.to_i
+          begin
+            node.delete_with_history!(new_node, user)
+            nodeversions[node.id]=node.version
+          rescue OSM::APIPreconditionFailedError => ex
+            # We don't do anything with the exception as the node is in use
+            # elsewhere and we don't want to delete it
+          end
+        end

 
 

-      # FIXME: would be good not to make two history entries when removing
-      #                 two nodes from the same relation
-      old_way = Way.find(way_id)
-      old_way.unshared_node_ids.each do |n|
-        deleteitemrelations(n, 'node')
-      end
-      deleteitemrelations(way_id, 'way')
-
-      way.delete_with_relations_and_nodes_and_history(changeset_id.to_i)
+      end # transaction
+      [0, '', way_id, old_way.version, nodeversions]

     end
     end

-    [0, way_id]

   end
 
 
   # ====================================================================
   # Support functions
 
   end
 
 
   # ====================================================================
   # Support functions
 

-  # Remove a node or way from all relations
-  # FIXME needs version, changeset, and user
-  def deleteitemrelations(objid, type) #:doc:
-    relations = RelationMember.find(:all, 
-                                                                       :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 }
-      # FIXME need to create the new node/way based on the type.
-      new_rel = Relation.new
-      new_rel.version = version
-      new_rel.members = members
-      new_rel.changeset = changeset
-      rel.delete_with_history(new_rel, user)
-    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
-  end
-

   # Authenticate token
   # (can also be of form user:pass)
   # When we are writing to the api, we need the actual user model, 
   # Authenticate token
   # (can also be of form user:pass)
   # When we are writing to the api, we need the actual user model, 


@@ -738,17 +831,6 @@ class AmfController < ApplicationController
     end
     return user
   end
     end
     return user
   end

-  
-  def getuserid(token)
-    user = getuser(token)
-    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)
-  end

 
   # Send AMF response
   
 
   # Send AMF response
   


@@ -809,7 +891,7 @@ class AmfController < ApplicationController
       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 
       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' 
+      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?
        WHERE #{OSM.sql_for_area(ymin, xmin, ymax, xmax, "cn.")}
       EOF
     unless way_ids.empty?


@@ -818,17 +900,17 @@ class AmfController < ApplicationController
         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
         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' 
+         WHERE crm.member_type='Way' 

          AND crm.member_id IN (#{way_ids.join(',')})
         EOF
     end
          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] }
+    ActiveRecord::Base.connection.select_all(sql).collect { |a| [a['relid'].to_i,a['version'].to_i] }

   end
        
   def sql_get_nodes_in_way(wayid)
     points=[]
     sql=<<-EOF
   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 
+      SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,current_nodes.id,current_nodes.version 

       FROM current_way_nodes,current_nodes 
        WHERE current_way_nodes.id=#{wayid.to_i} 
                   AND current_way_nodes.node_id=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 


@@ -841,7 +923,7 @@ class AmfController < ApplicationController
         nodetags[n['k']]=n['v']
       end
       nodetags.delete('created_by')
         nodetags[n['k']]=n['v']
       end
       nodetags.delete('created_by')

-      points << [row['lon'].to_f,row['lat'].to_f,row['id'].to_i,nodetags]
+      points << [row['lon'].to_f,row['lat'].to_f,row['id'].to_i,nodetags,row['version'].to_i]

     end
     points
   end
     end
     points
   end