Zipped filewatching

filewatch.gemspec

@@ -6,7 +6,7 @@ Gem::Specification.new do |spec|
   end
 
   spec.name = "filewatch"
-  spec.version = "0.5.0"
+  spec.version = "0.6.0"
   spec.summary = "filewatch - file watching for ruby"
   spec.description = "Watch files and directories in ruby. Also supports tailing and glob file patterns."
   spec.files = files

lib/filewatch/gzip.rb

@@ -0,0 +1,115 @@
+#!/usr/bin/env ruby
+# encoding: UTF-8
+
+require "filewatch/tail"
+require 'zlib'
+
+module FileWatch
+  class Gzip < Tail
+
+    # Public: Initialize a new FileWatch::Gzip object
+    #
+    # opts - An options hash (default: {})
+    #        :sincedb_write_interval - The Integer in seconds write to database (default: 10)
+    #        :stat_interval - The Integer in seconds to sleep inbetween stat checks (default: 1)
+    #        :discover_interval - The Integer in seconds to wait between globs (default: 5)
+    #        :exclude - The array of Strings to exclude from glob check (default: [])
+    #
+    # Examples
+    #
+    #   FileWatch::Gzip.new({:discover_interval => 10, :exclude => ['/tmp/*']})
+    #
+    def initialize(opts = {})
+      opts[:start_new_files_at] = :beginning
+      super(opts)
+    end
+
+    # Public: Watch a path for new gzipped files
+    #
+    # path - The String glob expression to watch for gzipped files
+    #
+    # Returns true if successfull, false otherwise
+    #
+    # Examples
+    #
+    #   gz = FileWatch::Gzip.new
+    #   gz.watch('/tmp/*gz') # => true
+    #
+    alias_method :watch, :tail
+
+    public
+    # Public: Initiates the loop that watches for files. Takes a block.
+    #
+    # block - Mandatory block. It will be sent the path to a file and a line
+    #         from that file.
+    #
+    # Yields - The path of a file, and a line within that file
+    #
+    # Examples
+    #
+    #   gz = FileWatch::Gzip.new
+    #   gz.watch('/tmp/*gz')
+    #   gz.subscribe{|path, line| puts "#{path}:#{line}"}
+    #
+    # Returns nothing. Runs infinitely.
+    #
+    def subscribe(&block)
+      @watch.subscribe(@opts[:stat_interval],
+                       @opts[:discover_interval]) do |event, path|
+        @logger.debug("#{self.class}#subscribe"){"Event: #{event} Path: #{path}"}
+
+        case event
+        when :create, :create_initial
+          if @files.member?(path)
+            @logger.debug("#{self.class}#subscribe"){"#{event} for #{path}: already exists in @files"}
+            next
+          end
+          if _open_file(path, event)
+            _read_file(path, &block)
+          end
+        when :modify
+          if [email protected]?(path)
+            @logger.debug(":modify for #{path}, does not exist in @files")
+          end
+        when :delete
+          @logger.debug(":delete for #{path}, deleted from @files")
+          @files[path].close
+          @files.delete(path)
+          @statcache.delete(path)
+        else
+          @logger.warn("unknown event type #{event} for #{path}")
+        end
+
+      end # @watch.subscribe
+    end # def subscribe
+
+    private
+    def _read_file(path, &block)
+      begin
+        changed = false
+        @logger.debug("#{self.class}#_read_file"){"GzipReader on #{path}"}
+        gz = Zlib::GzipReader.new(@files[path])
+        gz.each_line do |line|
+          changed = true
+          yield(path, line)
+        end
+        @sincedb[@statcache[path]] = @files[path].pos
+
+        if changed
+          now = Time.now.to_i
+          delta = now - @sincedb_last_write
+          if delta >= @opts[:sincedb_write_interval]
+            @logger.debug("writing sincedb (delta since last write = #{delta})")
+            _sincedb_write
+            @sincedb_last_write = now
+          end
+        end
+      rescue Zlib::Error, Zlib::GzipFile::Error, Zlib::GzipFile::NoFooter, Zlib::GzipFile::CRCError, Zlib::GzipFile::LengthError => e
+        @logger.debug("#{self.class}#_read_file"){"#{e.class}:#{e.message} path:#{path}"}
+      ensure
+        gz.close unless gz.nil?
+      end
+    end # _read_file
+
+  end # class Gzip
+end # module FileWatch