##
# sync a file to guarantee it's on disk
def fsync(f)
- File.open(f) do |fh|
- fh.fsync
- end
+ File.open(f, &:fsync)
end
##
# replicated to a file.
class Replicator
def initialize(config)
- @config = YAML.load(File.read(config))
- @state = YAML.load(File.read(@config["state_file"]))
+ @config = YAML.safe_load(File.read(config))
+ @state = YAML.safe_load(File.read(@config["state_file"]), [Time])
@conn = PGconn.connect(@config["db"])
- @now = Time.now.getutc
+ # get current time from the database rather than the current system
+ @now = @conn.exec("select now() as now").map { |row| Time.parse(row["now"]) }[0]
end
def open_changesets
last_run = @state["last_run"]
last_run = (@now - 60) if last_run.nil?
- @state["last_run"] = @now
# pretty much all operations on a changeset will modify its closed_at
# time (see rails_port's changeset model). so it is probably enough
# for us to look at anything that was closed recently, and filter from
doc.to_s
end
+ def sequence
+ @state.key?("sequence") ? @state["sequence"] + 1 : 0
+ end
+
+ def data_stem
+ @config["data_dir"] + format("/%03d/%03d/%03d", sequence / 1000000, (sequence / 1000) % 1000, (sequence % 1000))
+ end
+
+ def write_tmp_files!(changesets)
+ data_file = data_stem + ".osm.gz"
+ tmp_state = @config["state_file"] + ".tmp"
+ tmp_data = data_file + ".tmp"
+
+ FileUtils.mkdir_p(File.dirname(data_file))
+ Zlib::GzipWriter.open(tmp_data) do |fh|
+ fh.write(changeset_dump(changesets))
+ end
+ File.open(tmp_state, "w") do |fh|
+ fh.write(YAML.dump(@state))
+ end
+
+ # fsync the files in their old locations.
+ fsync(tmp_data)
+ fsync(tmp_state)
+
+ # sync the directory as well, to ensure that the file is reachable
+ # from the dirent and has been updated to account for any allocations.
+ fdirsync(File.dirname(tmp_data))
+ fdirsync(File.dirname(tmp_state))
+
+ # sanity check: the files we're moving into place
+ # should be non-empty.
+ raise "Temporary gzip file should exist, but doesn't." unless File.exist?(tmp_data)
+ raise "Temporary state file should exist, but doesn't." unless File.exist?(tmp_state)
+ raise "Temporary gzip file should be non-empty, but isn't." if File.zero?(tmp_data)
+ raise "Temporary state file should be non-empty, but isn't." if File.zero?(tmp_state)
+ end
+
+ def move_tmp_files_into_place!
+ data_file = data_stem + ".osm.gz"
+ data_state_file = data_stem + ".state.txt"
+ tmp_state = @config["state_file"] + ".tmp"
+ tmp_data = data_file + ".tmp"
+
+ FileUtils.mv(tmp_data, data_file)
+ FileUtils.cp(tmp_state, @config["state_file"])
+ FileUtils.mv(tmp_state, data_state_file)
+
+ # fsync the files in their new locations, in case the inodes have
+ # changed in the move / copy.
+ fsync(data_file)
+ fsync(@config["state_file"])
+ fsync(data_state_file)
+
+ # sync the directory as well, to ensure that the file is reachable
+ # from the dirent and has been updated to account for any allocations.
+ fdirsync(File.dirname(data_file))
+ fdirsync(File.dirname(@config["state_file"]))
+ end
+
# saves new state (including the changeset dump xml)
def save!
File.open(@config["state_file"], "r") do |fl|
fl.flock(File::LOCK_EX)
- sequence = (@state.key?("sequence") ? @state["sequence"] + 1 : 0)
- data_stem = @config["data_dir"] + format("/%03d/%03d/%03d", sequence / 1000000, (sequence / 1000) % 1000, (sequence % 1000))
- data_file = data_stem + ".osm.gz"
- data_state_file = data_stem + ".state.txt"
- tmp_state = @config["state_file"] + ".tmp"
- tmp_data = data_file + ".tmp"
# try and write the files to tmp locations and then
# move them into place later, to avoid in-progress
# clashes, or people seeing incomplete files.
begin
- FileUtils.mkdir_p(File.dirname(data_file))
- Zlib::GzipWriter.open(tmp_data) do |fh|
- fh.write(changeset_dump(open_changesets))
- end
+ changesets = open_changesets
@state["sequence"] = sequence
- File.open(tmp_state, "w") do |fh|
- fh.write(YAML.dump(@state))
- end
-
- # fsync the files in their old locations.
- fsync(tmp_data)
- fsync(tmp_state)
-
- # sync the directory as well, to ensure that the file is reachable
- # from the dirent and has been updated to account for any allocations.
- fdirsync(File.dirname(tmp_data))
- fdirsync(File.dirname(tmp_state))
-
- # sanity check: the files we're moving into place
- # should be non-empty.
- raise "Temporary gzip file should exist, but doesn't." unless File.exist?(tmp_data)
- raise "Temporary state file should exist, but doesn't." unless File.exist?(tmp_state)
- raise "Temporary gzip file should be non-empty, but isn't." if File.zero?(tmp_data)
- raise "Temporary state file should be non-empty, but isn't." if File.zero?(tmp_state)
-
- FileUtils.mv(tmp_data, data_file)
- FileUtils.cp(tmp_state, @config["state_file"])
- FileUtils.mv(tmp_state, data_state_file)
-
- # fsync the files in their new locations, in case the inodes have
- # changed in the move / copy.
- fsync(data_fie)
- fsync(@config["state_file"])
- fsync(data_state_file)
-
- # sync the directory as well, to ensure that the file is reachable
- # from the dirent and has been updated to account for any allocations.
- fdirsync(File.dirname(data_file))
- fdirsync(File.dirname(@config["state_file"]))
+ @state["last_run"] = @now
+
+ write_tmp_files!(changesets)
+
+ move_tmp_files_into_place!
fl.flock(File::LOCK_UN)
projects / chef.git / blobdiff