X-Git-Url: https://git.openstreetmap.org./chef.git/blobdiff_plain/8cdcbd941f99f13e2627c54d9c3efddbc946f52b..ab47927c016597f8602b81dcdc168ad5c335389d:/cookbooks/planet/files/default/replication-bin/replicate-changesets

diff --git a/cookbooks/planet/files/default/replication-bin/replicate-changesets b/cookbooks/planet/files/default/replication-bin/replicate-changesets
old mode 100644
new mode 100755
index 8132fa61b..77dc83312
--- a/cookbooks/planet/files/default/replication-bin/replicate-changesets
+++ b/cookbooks/planet/files/default/replication-bin/replicate-changesets
@@ -100,7 +100,7 @@ class ChangesetBuilder
     xml["comments_count"] = res.num_tuples.to_s
 
     # early return if there aren't any comments
-    return unless res.num_tuples > 0
+    return unless res.num_tuples.positive?
 
     discussion = XML::Node.new("discussion")
     res.each do |row|
@@ -117,21 +117,40 @@ class ChangesetBuilder
   end
 end
 
+##
+# sync a file to guarantee it's on disk
+def fsync(f)
+  File.open(f, &:fsync)
+end
+
+##
+# sync a directory to guarantee it's on disk. have to recurse to the root
+# to guarantee sync for newly created directories.
+def fdirsync(d)
+  while d != "/"
+    Dir.open(d) do |dh|
+      io = IO.for_fd(dh.fileno)
+      io.fsync
+    end
+    d = File.dirname(d)
+  end
+end
+
 ##
 # state and connections associated with getting changeset data
 # replicated to a file.
 class Replicator
   def initialize(config)
-    @config = YAML.load(File.read(config))
-    @state = YAML.load(File.read(@config["state_file"]))
-    @conn = PGconn.connect(@config["db"])
-    @now = Time.now.getutc
+    @config = YAML.safe_load(File.read(config))
+    @state = YAML.safe_load(File.read(@config["state_file"]), [Time])
+    @conn = PG::Connection.connect(@config["db"])
+    # 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
@@ -148,7 +167,7 @@ class Replicator
     new_ids = @conn
               .exec("select distinct changeset_id from changeset_comments where created_at >= '#{last_run}' and created_at < '#{@now}' and visible")
               .map { |row| row["changeset_id"].to_i }
-              .select { |c_id| !cs_ids.include?(c_id) }
+              .reject { |c_id| cs_ids.include?(c_id) }
 
     new_ids.each do |id|
       @conn
@@ -168,8 +187,8 @@ class Replicator
     { "version" => "0.6",
       "generator" => "replicate_changesets.rb",
       "copyright" => "OpenStreetMap and contributors",
-      "attribution" => "http://www.openstreetmap.org/copyright",
-      "license" => "http://opendatacommons.org/licenses/odbl/1-0/" }
+      "attribution" => "https://www.openstreetmap.org/copyright",
+      "license" => "https://opendatacommons.org/licenses/odbl/1-0/" }
       .each { |k, v| doc.root[k] = v }
 
     builder = ChangesetBuilder.new(@now, @conn)
@@ -180,43 +199,91 @@ class Replicator
     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)
+    File.open(@config["lock_file"], File::RDWR | File::CREAT, 0o600) do |fl|
+      # take the lock in non-blocking mode. if this process doesn't get the lock
+      # then another will be run from cron shortly. this prevents a whole bunch
+      # of processes queueing on the lock and causing weirdness if/when they
+      # get woken up in a random order.
+      got_lock = fl.flock(File::LOCK_EX | File::LOCK_NB)
+      return unless got_lock
 
-      sequence = (@state.key?("sequence") ? @state["sequence"] + 1 : 0)
-      data_file = @config["data_dir"] + format("/%03d/%03d/%03d.osm.gz", sequence / 1000000, (sequence / 1000) % 1000, (sequence % 1000))
-      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))
-          fh.fdatasync
-        end
+        changesets = open_changesets
         @state["sequence"] = sequence
-        File.open(tmp_state, "w") do |fh|
-          fh.write(YAML.dump(@state))
-          fh.fdatasync
-        end
-
-        # 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.mv(tmp_state, @config["state_file"])
-        fl.flock(File::LOCK_UN)
+        @state["last_run"] = @now
 
-      rescue
-        STDERR.puts("Error! Couldn't update state.")
+        write_tmp_files!(changesets)
+
+        move_tmp_files_into_place!
+
+        fl.flock(File::LOCK_UN)
+      rescue StandardError
+        warn "Error! Couldn't update state."
         fl.flock(File::LOCK_UN)
         raise
       end
@@ -228,6 +295,6 @@ begin
   rep = Replicator.new(ARGV[0])
   rep.save!
 rescue StandardError => e
-  STDERR.puts "ERROR: #{e.message}"
+  warn "ERROR: #{e.message}"
   exit 1
 end