Merge pull request #2485 from mmd-osm/patch/json2

JSON output nodes, ways, relations, map

app/controllers/api/map_controller.rb

@@ -5,6 +5,8 @@ module Api
     before_action :check_api_readable
     around_action :api_call_handle_error, :api_call_timeout
 
+    before_action :set_default_request_format
+
     # This is probably the most common call of all. It is used for getting the
     # OSM data for a specified bounding box, usually for editing. First the
     # bounding box (bbox) is checked to make sure that it is sane. All nodes
@@ -90,7 +92,10 @@ module Api
 
       response.headers["Content-Disposition"] = "attachment; filename=\"map.osm\""
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
   end
 end

app/controllers/api/nodes_controller.rb

@@ -13,6 +13,8 @@ module Api
     before_action :check_api_readable, :except => [:create, :update, :delete]
     around_action :api_call_handle_error, :api_call_timeout
 
+    before_action :set_default_request_format, :except => [:create, :update, :delete]
+
     # Create a node from XML.
     def create
       assert_method :put
@@ -32,7 +34,10 @@ module Api
 
       if @node.visible
         # Render the result
-        render :formats => [:xml]
+        respond_to do |format|
+          format.xml
+          format.json
+        end
       else
         head :gone
       end
@@ -73,7 +78,10 @@ module Api
       @nodes = Node.find(ids)
 
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
   end
 end

app/controllers/api/old_controller.rb

@@ -16,6 +16,8 @@ module Api
     before_action :lookup_old_element, :except => [:history]
     before_action :lookup_old_element_versions, :only => [:history]
 
+    before_action :set_default_request_format, :except => [:redact]
+
     def history
       # the .where() method used in the lookup_old_element_versions
       # call won't throw an error if no records are found, so we have
@@ -30,7 +32,10 @@ module Api
                end
 
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
 
     def version
@@ -41,7 +46,10 @@ module Api
         response.last_modified = @old_element.timestamp
 
         # Render the result
-        render :formats => [:xml]
+        respond_to do |format|
+          format.xml
+          format.json
+        end
       end
     end
 

app/controllers/api/relations_controller.rb

@@ -11,6 +11,8 @@ module Api
     before_action :check_api_readable, :except => [:create, :update, :delete]
     around_action :api_call_handle_error, :api_call_timeout
 
+    before_action :set_default_request_format, :except => [:create, :update, :delete]
+
     def create
       assert_method :put
 
@@ -26,7 +28,10 @@ module Api
       response.last_modified = @relation.timestamp
       if @relation.visible
         # Render the result
-        render :formats => [:xml]
+        respond_to do |format|
+          format.xml
+          format.json
+        end
       else
         head :gone
       end
@@ -117,7 +122,10 @@ module Api
         @relations << relation
 
         # Render the result
-        render :formats => [:xml]
+        respond_to do |format|
+          format.xml
+          format.json
+        end
       else
         head :gone
       end
@@ -133,7 +141,10 @@ module Api
       @relations = Relation.find(ids)
 
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
 
     def relations_for_way
@@ -160,7 +171,10 @@ module Api
       end
 
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
   end
 end

app/controllers/api/ways_controller.rb

@@ -11,6 +11,8 @@ module Api
     before_action :check_api_readable, :except => [:create, :update, :delete]
     around_action :api_call_handle_error, :api_call_timeout
 
+    before_action :set_default_request_format, :except => [:create, :update, :delete]
+
     def create
       assert_method :put
 
@@ -28,7 +30,10 @@ module Api
 
       if @way.visible
         # Render the result
-        render :formats => [:xml]
+        respond_to do |format|
+          format.xml
+          format.json
+        end
       else
         head :gone
       end
@@ -75,7 +80,10 @@ module Api
         end
 
         # Render the result
-        render :formats => [:xml]
+        respond_to do |format|
+          format.xml
+          format.json
+        end
       else
         head :gone
       end
@@ -93,7 +101,10 @@ module Api
       @ways = Way.find(ids)
 
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
 
     ##
@@ -106,7 +117,10 @@ module Api
       @ways = Way.where(:id => wayids, :visible => true)
 
       # Render the result
-      render :formats => [:xml]
+      respond_to do |format|
+        format.xml
+        format.json
+      end
     end
   end
 end

app/controllers/api_controller.rb

@@ -3,6 +3,56 @@ class ApiController < ApplicationController
 
   private
 
+  ##
+  # Set default request format to xml unless a client requests a specific format,
+  # which can be done via (a) URL suffix and/or (b) HTTP Accept header, where
+  # the URL suffix always takes precedence over the Accept header.
+  def set_default_request_format
+    unless params[:format]
+      accept_header = request.headers["HTTP_ACCEPT"]
+      if accept_header.nil?
+        # e.g. unit tests don't set an Accept: header by default, force XML in this case
+        request.format = "xml"
+        return
+      end
+
+      req_mimetypes = []
+
+      # Some clients (JOSM) send Accept headers which cannot be parsed by Rails, example: *; q=.2
+      # To be fair, JOSM's Accept header doesn't adhere to RFC 7231, section 5.3.1, et al. either
+      # As a workaround for backwards compatibility, we're assuming XML format
+      begin
+        req_mimetypes = Mime::Type.parse(accept_header)
+      rescue Mime::Type::InvalidMimeType
+        request.format = "xml"
+        return
+      end
+
+      # req_mimetypes contains all Accept header MIME types with descending priority
+      req_mimetypes.each do |mime|
+        if mime.symbol == :xml
+          request.format = "xml"
+          break
+        end
+
+        if mime.symbol == :json
+          request.format = "json"
+          break
+        end
+
+        # Any format, not explicitly requesting XML or JSON -> assume XML as default
+        if mime == "*/*"
+          request.format = "xml"
+          break
+        end
+
+        # In case the client requests some other format besides XML, JSON and */*,
+        # we deliberately don't set request.format. The framework will return an
+        # ActionController::UnknownFormat error to the client later on in this case.
+      end
+    end
+  end
+
   def authorize(realm = "Web Password", errormessage = "Couldn't authenticate you")
     # make the current_user object from any auth sources we have
     setup_user_auth

app/controllers/application_controller.rb

@@ -185,6 +185,8 @@ class ApplicationController < ActionController::Base
 
   def api_call_handle_error
     yield
+  rescue ActionController::UnknownFormat
+    head :not_acceptable
   rescue ActiveRecord::RecordNotFound => e
     head :not_found
   rescue LibXML::XML::Error, ArgumentError => e