X-Git-Url: https://git.openstreetmap.org./rails.git/blobdiff_plain/baf10cd39289cd7e94a819305e46f43e85a136c6..877716c72a3c0b1ad063d274546153099fd8bb78:/lib/diff_reader.rb diff --git a/lib/diff_reader.rb b/lib/diff_reader.rb index be6fee7bb..2784646af 100644 --- a/lib/diff_reader.rb +++ b/lib/diff_reader.rb @@ -4,14 +4,12 @@ # Uses the streaming LibXML "Reader" interface to cut down on memory # usage, so hopefully we can process fairly large diffs. class DiffReader - include ConsistencyValidations - # maps each element type to the model class which handles it MODELS = { - "node" => Node, - "way" => Way, + "node" => Node, + "way" => Way, "relation" => Relation - } + }.freeze ## # Construct a diff reader by giving it a bunch of XML +data+ to parse @@ -33,8 +31,8 @@ class DiffReader # NOTE: XML::Reader#read returns false for EOF and raises an # exception if an error occurs. @reader.read - rescue LibXML::XML::Error => ex - raise OSM::APIBadXMLError.new("changeset", xml, ex.message) + rescue LibXML::XML::Error => e + raise OSM::APIBadXMLError.new("changeset", xml, e.message) end ## @@ -57,12 +55,10 @@ class DiffReader # care of that for us. if @reader.node_type == 1 # element name = @reader.name - attributes = {} + attributes = {} if @reader.has_attributes? - while @reader.move_to_next_attribute == 1 - attributes[@reader.name] = @reader.value - end + attributes[@reader.name] = @reader.value while @reader.move_to_next_attribute == 1 @reader.move_to_element end @@ -85,8 +81,10 @@ class DiffReader def with_model with_element do |model_name, _model_attributes| model = MODELS[model_name] - fail OSM::APIBadUserInput.new("Unexpected element type #{model_name}, " + - "expected node, way or relation.") if model.nil? + if model.nil? + raise OSM::APIBadUserInput, "Unexpected element type #{model_name}, " \ + "expected node, way or relation." + end # new in libxml-ruby >= 2, expand returns an element not associated # with a document. this means that there's no encoding parameter, # which means basically nothing works. @@ -109,10 +107,8 @@ class DiffReader # Checks a few invariants. Others are checked in the model methods # such as save_ and delete_with_history. def check(model, xml, new) - fail OSM::APIBadXMLError.new(model, xml) if new.nil? - unless new.changeset_id == @changeset.id - fail OSM::APIChangesetMismatchError.new(new.changeset_id, @changeset.id) - end + raise OSM::APIBadXMLError.new(model, xml) if new.nil? + raise OSM::APIChangesetMismatchError.new(new.changeset_id, @changeset.id) unless new.changeset_id == @changeset.id end ## @@ -124,34 +120,34 @@ class DiffReader # an exception subclassing OSM::APIError will be thrown. def commit # data structure used for mapping placeholder IDs to real IDs - node_ids, way_ids, rel_ids = {}, {}, {} - ids = { :node => node_ids, :way => way_ids, :relation => rel_ids } + ids = { :node => {}, :way => {}, :relation => {} } # take the first element and check that it is an osmChange element @reader.read - fail OSM::APIBadUserInput.new("Document element should be 'osmChange'.") if @reader.name != 'osmChange' + raise OSM::APIBadUserInput, "Document element should be 'osmChange'." if @reader.name != "osmChange" - result = OSM::API.new.get_xml_doc + result = OSM::API.new.xml_doc result.root.name = "diffResult" # loop at the top level, within the element with_element do |action_name, action_attributes| - if action_name == 'create' + case action_name + when "create" # create a new element. this code is agnostic of the element type # because all the elements support the methods that we're using. with_model do |model, xml| - new = model.from_xml_node(xml, true) + new = model.from_xml_node(xml, :create => true) check(model, xml, new) # when this element is saved it will get a new ID, so we save it # to produce the mapping which is sent to other elements. - placeholder_id = xml['id'].to_i - fail OSM::APIBadXMLError.new(model, xml) if placeholder_id.nil? + placeholder_id = xml["id"].to_i + raise OSM::APIBadXMLError.new(model, xml) if placeholder_id.nil? # check if the placeholder ID has been given before and throw # an exception if it has - we can't create the same element twice. model_sym = model.to_s.downcase.to_sym - fail OSM::APIBadUserInput.new("Placeholder IDs must be unique for created elements.") if ids[model_sym].include? placeholder_id + raise OSM::APIBadUserInput, "Placeholder IDs must be unique for created elements." if ids[model_sym].include? placeholder_id # some elements may have placeholders for other elements in the # diff, so we must fix these before saving the element. @@ -171,12 +167,12 @@ class DiffReader result.root << xml_result end - elsif action_name == 'modify' + when "modify" # modify an existing element. again, this code doesn't directly deal # with types, but uses duck typing to handle them transparently. with_model do |model, xml| # get the new element from the XML payload - new = model.from_xml_node(xml, false) + new = model.from_xml_node(xml, :create => false) check(model, xml, new) # if the ID is a placeholder then map it to the real ID @@ -203,14 +199,14 @@ class DiffReader result.root << xml_result end - elsif action_name == 'delete' + when "delete" # delete action. this takes a payload in API 0.6, so we need to do # most of the same checks that are done for the modify. with_model do |model, xml| # delete doesn't have to contain a full payload, according to # the wiki docs, so we just extract the things we need. - new_id = xml['id'].to_i - fail OSM::APIBadXMLError.new(model, xml, "ID attribute is required") if new_id.nil? + new_id = xml["id"].to_i + raise OSM::APIBadXMLError.new(model, xml, "ID attribute is required") if new_id.nil? # if the ID is a placeholder then map it to the real ID model_sym = model.to_s.downcase.to_sym @@ -219,8 +215,8 @@ class DiffReader # build the "new" element by modifying the existing one new = model.find(id) - new.changeset_id = xml['changeset'].to_i - new.version = xml['version'].to_i + new.changeset_id = xml["changeset"].to_i + new.version = xml["version"].to_i check(model, xml, new) # fetch the matching old element from the DB @@ -251,7 +247,7 @@ class DiffReader else # no other actions to choose from, so it must be the users fault! - fail OSM::APIChangesetActionInvalid.new(action_name) + raise OSM::APIChangesetActionInvalid, action_name end end